Toelatingsnummer 13848 N

Mission  

 

13848 N

 

 

 

 

 

 

 

 

HET COLLEGE VOOR DE TOELATING VAN

GEWASBESCHERMINGSMIDDELEN EN BIOCIDEN

 

1 WEDERZIJDSE ERKENNING

 

Gelet op de aanvraag d.d. 24 april 2007 (20070449 WERG) van

 

Agrichem B.V.

Koopvaardijweg 9

4906 CV  OOSTERHOUT NB

 

 

 

tot verkrijging van een wederzijdse erkenning van de toelating in het Verenigd Koninkrijk van het gewasbeschermingsmiddel op basis van de werkzame stof  diquat dibromide,

 

Mission

 

gelet op artikel 36, Wet gewasbeschermingsmiddelen en biociden,

 

BESLUIT HET COLLEGE als volgt:

 

1.1  Toelating

1.      Het middel Mission is toegelaten voor de in bijlage I genoemde toepassingen onder nummer 13848 N met ingang van datum dezes. Voor de gronden van dit besluit wordt verwezen naar bijlage II bij dit besluit.

2.      De toelating geldt tot 31 december 2015.

 

1.2  Samenstelling, vorm en verpakking

De toelating geldt uitsluitend voor het middel in de samenstelling, vorm en de verpakking als waarvoor de toelating is verleend.

 

1.3  Gebruik

Het middel mag slechts worden gebruikt met inachtneming van hetgeen in bijlage I onder A bij dit besluit is voorgeschreven.

 


1.4 Classificatie en etikettering

Gelet op artikel 80, vijfde lid Verordening (EG) 1107/2009 juncto artikel 29, eerste lid, sub d, Wet gewasbeschermingsmiddelen en biociden,

 

1.    De aanduidingen, welke ingevolge artikelen 9.2.3.1 en 9.2.3.2 van de Wet milieubeheer en artikelen 14, 15a, 15b, 15c en 15e van de Nadere regels verpakking en aanduiding milieugevaarlijke stoffen en preparaten op de verpakking moeten worden vermeld, worden hierbij vastgesteld als volgt:

 

aard van het preparaat: Met water mengbaar concentraat

 

werkzame stof:

gehalte:

diquat dibromide

374 g/l

uitgedrukt als diquat

200 g/l

 

 

 

letterlijk en zonder enige aanvulling:

 

andere zeer giftige, giftige, bijtende of schadelijke stof(fen): -

 

Gevaarsymbool:

aanduiding:

T

Vergiftig

N

Milieugevaarlijk

 

 

Waarschuwingszinnen: 

 

R22                 -Schadelijk bij opname door de mond.

R23                 -Vergiftig bij inademing.

R36/37/38       -Irriterend voor de ogen, de ademhalingswegen en de huid.

R43                 -Kan overgevoeligheid veroorzaken bij contact met de huid.

R48/25            -Vergiftig: gevaar voor ernstige schade aan de gezondheid bij langdurige blootstelling bij opname door de mond.R50/53     -Zeer vergiftig voor in het water levende organismen; kan in het aquatisch milieu op lange termijn schadelijke effecten veroorzaken.

R50/53            Zeer vergiftig voor in het water levende organismen; kan in het aquatisch milieu op lange termijn schadelijke effecten veroorzaken.

 

 

Veiligheidsaanbevelingen:

 

S21                 -Niet roken tijdens gebruik.

S36/37            -Draag geschikte handschoenen en beschermende kleding.

S42b               -Tijdens de bespuiting een geschikte ademhalingsbescherming dragen.

S42j                -Draag een geschikte adembescherming gedurende het mengen en laden van het middel.

S45                 -Bij een ongeval of indien men zich onwel voelt onmiddellijk een arts raadplegen (indien mogelijk hem dit etiket tonen).

S60                 -Deze stof en de verpakking als gevaarlijk afval afvoeren. (Deze zin hoeft niet te worden vermeld op het etiket indien u deelneemt aan het verpakkingenconvenant, en op het etiket het STORL-vignet voert, en ingevolge dit convenant de toepasselijke zin uit de volgende verwijderingszinnen op het etiket vermeldt:

Deze verpakking is bedrijfsafval, mits deze is schoongespoeld, zoals wettelijk is voorgeschreven.

Deze verpakking is bedrijfsafval, nadat deze volledig is geleegd.

Deze verpakking dient nadat deze volledig is geleegd te worden ingeleverd bij een KCA-depot. Informeer bij uw gemeente.)

S61                 -Voorkom lozing in het milieu. Vraag om speciale instructies / veiligheidsgegevenskaart.

SPo 2              -Was alle beschermende kleding na gebruik.

V30-NL            -Beschermen tegen bevriezen.

 

 

Specifieke vermeldingen:

 

DPD01            -Volg de gebruiksaanwijzing om gevaar voor mens en milieu te voorkomen.

 

  1. Behalve de onder 1. bedoelde en de overige bij de Wet Milieugevaarlijke Stoffen en Nadere regels verpakking en aanduiding milieugevaarlijke stoffen en preparaten voorge­schreven aanduidingen en vermeldingen moeten op de verpakking voorkomen:

 

    1. letterlijk en zonder enige aanvulling:
      het wettelijk gebruiksvoorschrift
      De tekst van het wettelijk gebruiksvoorschrift is opgenomen in Bijlage I.

 

 

2 DETAILS VAN DE AANVRAAG

 

Het betreft een aanvraag tot verkrijging van een toelating van het middel Mission (13848 N), een middel op basis van de werkzame stof  diquat dibromide. Het middel wordt aangevraagd voor de volgende toepassingen:

·                     doodspuitmiddel in aardappelen, droog te oogsten erwten, veldbonen (voor ensilage), rode en witte klaver (zaadproductie), winter- en zomergerst, haver, koolzaad, lijnzaad en hop.

·                     onkruidbestrijdingsmiddel in aardappelen, bieten, peulvruchten, witlof (pennenteelt), cichorei,  aardbei (onbedekt), bladgroenten (onbedekt), peulgroenten (onbedekt), vruchtgroenten (onbedekt), koolgewassen (onbedekt), wortel- en knolgewassen (onbedekt), ui-achtigen, stengelgroenten (onbedekt), kruidenteelt vers of gedroogd (onbedekt), bloembol- en bloemknolgewassen (onbedekt), bloemisterijgewassen (onbedekt), granen, mais, peulvruchten, veldbonen, graszaad, koolzaad, voedergewassen, fruitgewassen, vruchtgroenten en siergewassen.

 

2.2 Informatie met betrekking tot de stof

Er zijn in Nederland reeds andere middelen op basis van de werkzame stof  diquat dibromide toegelaten. De stof is per 1 januari 2002 geplaatst op Annex I van richtlijn 91/414 (Richtlijn 2001/21/EG, 5 maart 2001), en  tevens goedgekeurd krachtens Verordening (EG) No 1107/2009 (Uitvoeringsverordening (EU) No 540/2011 d.d. 25 mei 2011) en geplaatst als stof 15 in de bijlage.

 

2.3 Karakterisering van het middel

Diquat dibromide wordt snel opgenomen door bladeren en groene stengeldelen en verplaatst zich niet of nauwelijks binnen de plant. Behandelde planten verwelken snel en verdorren binnen een paar uur na toepassing. Voor optimale herbicide activiteit is licht nodig omdat diquat dibromide het fotosynthese elektronentransport verhindert. Door dit verminderde elektronentransport worden fytotoxische vrije radicalen gevormd die schade toebrengen aan de celmembranen waardoor de planten verwelken.

 

2.4 Voorgeschiedenis

De aanvraag is op 25 april 2007 ontvangen; op 24 april 2007 zijn de verschuldigde aanvraagkosten ontvangen. Bij brief d.d. 17 april 2009 is de aanvraag in behandeling genomen.

 

 

3  RISICOBEOORDELINGEN

De beoordeling is uitgevoerd conform RGB H2 en HTB 1.0.

 

3.1  Inleiding

De onderhavige aanvraag betreft een verzoek tot wederzijdse erkenning van de toelating in het Verenigd Koninkrijk van het gewasbeschermingsmiddel Mission. Gezien de aard van de wederzijdse erkenning wordt ervan uitgegaan dat de beoordeling door het Verenigd Koninkrijk is uitgevoerd conform de Uniforme Beginselen (annex VI bij richtlijn 91/414/EEG).

 

Voor de beoordeling van de aspecten fysische en chemische eigenschappen, analysemethoden, werkzaamheid en delen van de aspecten risico voor de mens en risico voor het milieu refereert het Ctgb aan het toelatingsbesluit in het Verenigd Koninkrijk.

Op een aantal hieronder weergegeven voor de Nederlandse situatie specifieke punten, toetst het Ctgb zelf inhoudelijk.

 

3.2  Risico voor de mens

De volgende aspecten worden nationaal ingevuld:

·          Arbeidsomstandigheden - nationale modellen en arbeidshygiënische strategie

·          Volksgezondheid - de criteria voor residuen in volggewassen

Het middel voldoet aan de voorwaarde dat het, rekening houdend met alle normale omstandigheden waaronder het middel kan worden gebruikt en de gevolgen van het gebruik, geen directe of indirecte schadelijke uitwerking heeft op de gezondheid van de mens. De beoordeling van het risico voor de toepasser staat beschreven in Hoofdstuk 4 Mammalian Toxicology, van Bijlage II bij dit besluit.

De beoordeling van het risico voor de volksgezondheid met betrekking tot residuen in volggewassen staat beschreven in Hoofdstuk 5, Residues van bijlage II behorende bij dit besluit.

 

3.3  Risico voor het milieu

De volgende aspecten worden nationaal ingevuld:

·         Uitspoeling naar grondwater

·         Drift naar oppervlaktewater; van toepassing op : Waterorganismen, vogels, zoogdieren, niet-doelwitplanten, niet-doelwitarthropoden en oppervlaktewater bestemd voor de bereiding van drinkwater

·         Drinkwatercriterium oppervlaktewater.

Toepassing van het middel zoals aangegeven in het Wettelijk Gebruiksvoorschrift (Bijlage I) voldoet aan de voorwaarde dat het, rekening houdend met alle normale omstandigheden waaronder het middel kan worden gebruikt en de gevolgen van het gebruik, geen voor het milieu onaanvaardbaar effect heeft, waarbij in het bijzonder rekening wordt gehouden met de volgende aspecten:

·         de plaats waar het middel in het milieu terechtkomt en wordt verspreid, met name voor wat betreft besmetting van het water, waaronder drinkwater en grondwater,

·         de gevolgen voor niet-doelsoorten.

(artikel 28, eerste lid, sub b, onderdeel 4 en 5, Wet gewasbeschermingsmiddelen en biociden).

De beoordeling van het risico voor het milieu staat beschreven in Hoofdstuk 6, Environmental Fate and Behaviour, en Hoofdstuk 7, Ecotoxicology, in Bijlage II bij dit besluit.

 

3.4  Eindconclusie

Bij gebruik volgens het Wettelijk Gebruiksvoorschrift is het middel Mission op basis van de werkzame stof  diquat dibromide voldoende werkzaam en heeft het geen schadelijke uitwerking op de gezondheid van de mens en het milieu (artikel 80, vijfde lid Verordening (EG) 1107/2009 juncto artikel 80, vijfde lid Verordening (EG) 1107/2009 juncto artikel 28, Wet gewasbeschermingsmiddelen en biociden).

 

 

Degene wiens belang rechtstreeks bij dit besluit is betrokken kan gelet op artikel 119, eerste lid, Wet gewasbeschermingsmiddelen en biociden en artikel 7:1, eerste lid, van de Algemene wet bestuursrecht, binnen zes weken na de dag waarop dit besluit bekend is gemaakt een bezwaarschrift indienen bij: het College voor de toelating van gewasbeschermingsmiddelen en biociden (Ctgb), Postbus 217, 6700 AE WAGENINGEN. Het Ctgb heeft niet de mogelijkheid van het elektronisch indienen van een bezwaarschrift opengesteld.

 

 

Wageningen, 9 november 2012

 

 

HET COLLEGE VOOR DE TOELATING VAN  GEWASBESCHERMINGSMIDDELEN EN  BIOCIDEN,





ir. J.F. de Leeuw

voorzitter

 

 


HET COLLEGE VOOR DE TOELATING VAN GEWASBESCHERMINGSMIDDELEN EN BIOCIDEN

 

BIJLAGE I bij het besluit d.d. 9 november 2012 tot toelating van het middel Mission, toelatingnummer 13848 N

 

Wettelijk Gebruiksvoorschrift

Toegestaan is uitsluitend het professionele gebruik als onkruidbestrijdingsmiddel of doodspuitmiddel in de volgende toepassingsgebieden (volgens Definitielijst toepassingsgebieden versie 2.0, Ctgb juni 2011) onder de vermelde toepassingsvoorwaarden:

 

Toepassingsgebied

Type toepassing

Te bestrijden organisme

Dosering (middel) per toepassing

Maximaal aantal toepassingen per teeltcyclus of per 12 maanden

Veiligheidstermijn in dagen

Aardappelen

voor opkomst

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1 per teeltcyclus

-

 

Doodspuiten

Aardappelloof

4 l/ha

1 per teeltcyclus

-

Bieten

voor opkomst

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1 per teeltcyclus

-

 

Bladgroenten (onbedekt)

voor opkomst of voor uitplanten

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1 per 12 maanden

-

 

Peulgroenten (onbedekt)

voor opkomst

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1  per teeltcyclus

-

 

Vruchtgroenten (onbedekt)

voor opkomst of voor uitplanten

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1  per teeltcyclus

-

Koolgewassen (onbedekt)

voor opkomst of voor uitplanten

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1 per 12 maanden

-

Wortel- en knolgewassen (onbedekt)

voor opkomst

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1 per 12 maanden

-

Stengelgroenten (onbedekt)

voor opkomst of voor uitplanten

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1 per 12 maanden

-

Bloembol- en bloemknolgewassen (onbedekt)

voor opkomst of voor uitplanten

Eenjarige breedbladige onkruiden

1,5-2 l/ha

1 per 12 maanden

-

Mission in een watervolume van 200-500 l/ha toepassen.

 

Toepassingsvoorwaarden

Om niet tot de doelsoorten behorende geleedpotigen / insecten en niet tot de doelsoorten behorende planten te beschermen is de toepassing uitsluitend toegestaan indien gebruik wordt gemaakt van  minimaal 75% driftreducerende spuitdoppen met een kantdop en een bufferzone van 1,5 m.

 

Gevaarlijk voor bijen en hommels. Om de bijen en andere bestuivende insecten te beschermen mag u dit product niet gebruiken op in bloei staande gewassen of op niet-bloeiende gewassen wanneer deze actief bezocht worden door bijen en hommels. Gebruik dit product niet wanneer bloeiende onkruiden aanwezig zijn.

 

 

 

 

 

 

 


 

 

HET COLLEGE VOOR DE TOELATING VAN GEWASBESCHERMINGSMIDDELEN EN BIOCIDEN

 

BIJLAGE II bij het besluit d.d. 9 november 2012 tot toelating van het middel Mission, toelatingnummer 13848 N

 

Contents

                                                                                                                                              Page

1.     Identity of the plant protection product 2

2.     Physical and chemical properties. 2

3.     Methods of analysis. 3

4.     Mammalian toxicology. 3

5.     Residues. 9

6.     Environmental fate and behaviour. 9

7.     Ecotoxicology. 20

8.     Efficacy. 46

9.     Conclusion. 47

10.       Classification and labelling. 48

 

 

The next uses are withdrawn by applicant (see paragraph 7.1.1 for further details):

 

Interrow weed control in:

* Cereals;

* Maize;

* dry harvested beans;

* dry field beans;

* grass seed;

* oilseed;

* green forage;

* fruit crops (pome fruit, stone fruit, berries and small fruit);

* fruiting vegetables;

* Ornamentals (nursery, forestry, perennials, other ornamentals).

 

Desiccation in:

* winter- and spring barley, oats;

* oilseed rape;

* linseed;

* hop.

 

 

 


1.      Identity of the plant protection product

 

1.1       Applicant

Agrichem B.V.

Koopvaardijweg 9

4906 CV Oosterhout

 

1.2       Identity of the active substance

Common name

Diquat

Name in Dutch

Diquat

Chemical name

9,10-dihydro-8a,10a-diazoniaphenanthrene ion (diquat) [IUPAC]

CAS no

2764-72-9 (diquat), 85-00-7 (diquat dibromide)

EC no

220-433-0 (diquat), 201-579-4 (diquat dibromide)

 

The active substance was included on January 1st 2002 in the Annex I list of Directive 91/414/EC.

 

1.3       Identity of the plant protection product

Name

Mission

Formulation type

SL, Soluble concentrate

Content active substance

200 g/l pure diquat, equivalent to 374 g/l pure diquat-dibromide

 

The formulation was assessed in the United Kingdom according to the Uniform Principles of 91/414/EC.

 

1.4       Function

Dessicant and herbicide.

 

1.5       Uses applied for

See GAP (Appendix I).

 

1.6              Background to the application

It concerns an application for the mutual recognition of the plant protection product Mission, based on the authorisation in the UK (MAPP 13411).

 

1.7       Packaging details

 

1.7.1    Packaging description

Material:

HDPE container

Capacity:

1, 5 or 10L

Type of closure and size of opening:

Srew cap with induction seal, resp. 45 mm, 63 mm, 63 mm

Other information

ADR/UN compliant

 

1.7.2    Detailed instructions for safe disposal

See application form and MSDS (no particular recommendations)

 

 

2.      Physical and chemical properties

For the assessment of the physical and chemical properties of Mission we refer to the member state of the original authorisation (UK).

 

 

3.      Methods of analysis

 

For the assessment of the methods of analysis required for Mission we refer to the member state of the original authorisation (UK).

 

3.4       Physical-chemical classification and labelling

 

Proposal for the classification and labelling of the formulation concerning physical chemical properties

Based on the profile of the substance, the provided toxicology of the preparation, the  characteristics of the co-formulants, the method of application, the following labelling of the preparation is proposed:

 

Substances, present in the formulation, which should be mentioned on the label by their chemical name (other very toxic, toxic, corrosive or harmful substances):

-

Symbol:

-

Indication of danger:

-

R phrases

-

-

S phrases

V30-NL

Protect from frost

 

S21

When using do not smoke

Special provisions:
DPD-phrases

-

-

Child-resistant fastening obligatory?

-

Tactile warning of danger obligatory?

-

 

Explanation:

Hazard symbol:

-

Risk phrases:

-

Safety phrases:

Formulation not stable below 0 °C

 

S21 is assigned to formulations with halogenated components due to the risk of development of toxic gases when incinerated or burned.

Other:

-

Supported shelf life of the formulation: 2 years.

 

 

4.      Mammalian toxicology

 

4.1       Toxicity of the formulated product (IIIA 7.1)

For the evaluation of the toxicity of the formulated product Mission, we refer to the member state of the original authorisation (Member State).

 

4.2       Dermal absorption (IIIA 7.3)

The United Kingdom used a value of 1% for dermal absorption in the risk assessment and since this application is a request for mutual recognition a value of 1% is also used in this risk assessment.

 

4.3       Available toxicological data relating to non-active substances (IIIA 7.4)

For toxicological data relating to non-active substances we refer to the registration report written by UK.

 

 

 

 

4.4       Exposure/risk assessments (Dutch specific aspect)

 

Overview of the intended uses

An application (request for mutual recognition) has been submitted for the authorisation of the plant protection product Mission, a herbicide based on the active substance diquat.

 

Mission is a SL formulation and contains 200 g/L diquat.

 

The formulation Mission is applied by mechanical downward spraying in agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop. The formulation is applied once with a maximum dose of 4 L formulation / ha. Therefore, a semi-chronic exposure duration is applicable for the operator (including contract workers).

 

The formulation Mission can also be applied by manual downward spraying in herbs. The formulation is applied once with a maximum dose of 2 L formulation / ha. Therefore, a semi-chronic exposure duration is applicable for the operator (including contract workers).

 

4.4.1    Operator exposure/risk

According to the Dutch Plant Protection Products and Biocides Regulations the risk assessment is performed according to a tiered approach. There are four possible tiers:

Tier 1: Risk assessment using the EU-AOEL without the use of PPE

Tier 2: Risk assessment using the NL-AOEL without the use of PPE

Tier 3: Refinement of the risk assessment using new dermal absorption data

Tier 4: Prescription of PPE

 

Tier 1

 

Calculation of the EU-AOEL / Tolerable Limit Value (TLV)

For diquat no TLV has been set. The AOEL will be used for the risk assessment.

Since diquat is included in Annex I of 91/414/EEC, the semi-chronic EU-AOEL of 0.001 mg/kg bw/day (= 0.07 mg/day for a 70-kg operator), based on the 2-year study in rat (90-day endpoint) is applied. This AOEL has also been used in the risk assessment performed by the United Kingdom.

 

Exposure/risk

Exposure to diquat during mixing and loading and application of Mission is estimated with models. The exposure is estimated for the unprotected operator. In general, mixing and loading and application is performed by the same person. Therefore, for the total exposure, the respiratory and dermal exposure during mixing/loading and application have to be combined.

In the Table below the estimated internal exposure is compared with the systemic EU-AOEL. For each application method, the exposure is only estimated with the highest dose.

 


Table T.1 Internal operator exposure to diquat and risk assessment for the use of Mission

 

Route

Estimated internal exposure a (mg/day)

Systemic

EU-AOEL

(mg/day)

Risk-index b

Mechanical downward spraying on agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop (4 L/ha, uncovered)

Mixing/

Loadingc

Respiratory

0.04

0.07

0.57

Dermal

1.60

0.07

22.86

Applicationc

Respiratory

0.06

0.07

0.91

Dermal

0.24

0.07

3.43

 

Total

1.94

0.07

27.77

Manual downward spraying on herbs (2 L/ha, uncovered)

Mixing/

Loading

Respiratoryd

< 0.01

0.07

< 0.01

Dermalc

0.21

0.07

2.97

Applicatione

Respiratory

0.10

0.07

1.37

Dermal

0.82

0.07

11.66

 

Total

1.13

0.07

16.14

a    Internal exposure was calculated with:

·       biological availability via the dermal route: 1% (concentrate) and 1% (spray dilution) (see 4.2)

·       biological availability via the respiratory route: 100% (worst case)

b    The risk-index is calculated by dividing the internal exposure by the systemic AOEL.

c    External exposure is estimated with  EUROPOEM.

d    External exposure is estimated with  NL-model.

e    External exposure is estimated with  UK POEM.

 

Since the EU-AOEL is exceeded without the use of PPE, a tier 2 assessment has to be performed using the NL-AOEL.

 

Tier 2

 

Calculation of the NL-AOEL

The risk index calculated with the EU-AOEL is >1. Therefore, the Plant Protection Products and Biocides Regulations (NL: Rgb) prescribes the calculation of the risk with an AOEL based on allometric extrapolation (known as the NL-AOEL). This method takes into account the caloric demand of the species studied and results in a more specific value than the EU-AOEL for which a standard factor of 100 is applied.

 

The calculation of the systemic AOEL for semi-chronic exposure is based on the NOAEL of 1 mg/kg bw/day in the 2-year study with the rat (90 day endpoint). Calculations from other studies result in higher AOELs.

Safety factors are used to compensate for the uncertainties, which arise, for example, from extrapolation from the tested species to humans and the differences between experimental circumstances, and to ensure that at the acceptable exposure level no adverse health effects will occur.

 

Used factors are:

·       extrapolation rat ® human on basis of caloric demand                                     4

·       other interspecies differences:                                                                            3

·       intraspecies differences: (professional use)                                                       3

·       biological availability via oral route:                                                                      10%*

·       weight of professional operator/worker:                                                              70 kg

* If the absorbed dose is significantly lower (<80%) than the administered dose, this is adjusted by a correction factor equal to the percentage absorption.

 

AOELsystemic: 1 x 0.1 x 70 / (4 x 3 x 3) = 0.2 mg/day

 

Exposure/risk

 

Table T.2 Internal operator exposure to diquat and risk assessment for the use of Mission

 

Route

Estimated internal exposure a (mg/day)

Systemic

NL-AOEL

(mg/day)

Risk-index b

Mechanical downward spraying on agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop (4 L/ha, uncovered)

Mixing/

Loadingc

Respiratory

0.04

0.2

0.20

Dermal

1.60

0.2

8.00

Applicationc

Respiratory

0.06

0.2

0.32

Dermal

0.24

0.2

1.20

 

Total

1.94

0.2

9.72

Manual downward spraying on herbs (2 L/ha, uncovered)

Mixing/

Loading

Respiratoryd

< 0.01

0.2

< 0.01

Dermalc

0.21

0.2

1.04

Applicatione

Respiratory

0.10

0.2

0.48

Dermal

0.82

0.2

4.08

 

Total

1.13

0.2

5.65

a    Internal exposure was calculated with:

·       biological availability via the dermal route: 1% (concentrate) and 1% (spray dilution) (see 4.2)

·       biological availability via the respiratory route: 100% (worst case)

b    The risk-index is calculated by dividing the internal exposure by the systemic AOEL.

c    External exposure is estimated with  EUROPOEM.

d    External exposure is estimated with  NL-model.

e    External exposure is estimated with  UK POEM.

 

Since the NL-AOEL is exceeded without the use of PPE, a tier 3 assessment has to be performed.

 

Tier 3

 

Since the results of acceptable dermal absorption studies were already used in tier 1 and 2, a further refinement with additional dermal absorption data is not considered relevant and a tier 4 assessment will be performed.

 

Tier 4

 

The NL-AOEL is exceeded without the use of PPE and dermal absorption data have already been taken into account in the risk assessment. Therefore, in Tier 4 a risk assessment is performed with and without the use of PPE.

 

 

 

 

 

Table T.3 Internal operator exposure to diquat and risk assessment for the use of Mission

 

Route

Estimated internal exposure a (mg/day)

Systemic

NL-AOEL

(mg/day)

Risk-index b

without

PPE

with

PPE

without

PPE

with

PPE

Mechanical downward spraying on agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop (4 L/ha, uncovered)

Mixing/

Loadingc

Respiratory

0.04

< 0.01

0.2

0.20

0.02

Dermal

1.60

0.16

0.2

8.00

0.80

Applicationc

Respiratory

0.06

0.01

0.2

0.32

0.03

Dermal

0.24

0.02

0.2

1.20

0.12

 

Total

1.94

0.19

0.2

9.72

0.97f

Manual downward spraying on herbs (2 L/ha, uncovered)

Mixing/

Loading

Respiratoryd

< 0.01

(< 0.01)

0.2

< 0.01

(< 0.01)

Dermalc

0.21

0.02

0.2

1.04

0.10

Applicatione

Respiratory

0.10

(0.10)

0.2

0.48

(0.48)

Dermal

0.82

0.08

0.2

4.08

0.40

 

Total

1.13

0.20

0.2

5.65

1.00g

a    Internal exposure was calculated with:

·       biological availability via the dermal route: 1% (concentrate) and 1% (spray dilution) (see 4.2)

·       biological availability via the respiratory route: 100% (worst case)

b    The risk-index is calculated by dividing the internal exposure by the systemic AOEL.

c    External exposure is estimated with  EUROPOEM.

d    External exposure is estimated with  NL-model.

e    External exposure is estimated with  UK POEM.

f     PPE: respiratory personal protective equipment, gloves and coverall during mixing/loading and application.

g    PPE: gloves and coverall during mixing/loading and application.

 

4.4.2    Bystander exposure/risk

 

Tier 1

 

The exposure is estimated for the unprotected bystander. In Table T.4 the estimated internal exposure is compared with the systemic EU-AOEL.

 

Table T.4 Internal bystander exposure to diquat and risk assessment after application

of Mission

 

Route

Estimated internal exposure a (mg/day)

Systemic

EU-AOEL

(mg/day)

Risk-index b

Bystander exposure during application in agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop

 

Respiratory

0.15

0.07

2.14

Dermal

0.01

0.07

0.11

 

Total

0.16

0.07

2.25

a       External exposure was estimated with EUROPOEM II. Internal exposure was calculated with:

·       biological availability via the dermal route: 1% (see 4.2)

·       biological availability via the respiratory route: 100% (worst case)

b       The risk-index is calculated by dividing the internal exposure by the systemic AOEL.

 

Since the EU-AOEL is exceeded without the use of PPE, a tier 2 assessment has to be performed using the NL-AOEL.

 

Tier 2

 

Table T.5 Internal bystander exposure to diquat and risk assessment after application of

Mission

 

Route

Estimated internal exposure a (mg day)

Systemic

NL-AOEL

(mg/day)

Risk-index b

Bystander exposure during application in agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop

 

Respiratory

0.15

0.2

0.75

Dermal

0.01

0.2

0.04

 

Total

0.16

0.2

0.79

a       External exposure was estimated with EUROPOEM II. Internal exposure was calculated with:

·       biological availability via the dermal route: 1% (see 4.2)

·       biological availability via the respiratory route: 100% (worst case)

b       The risk-index is calculated by dividing the internal exposure by the systemic AOEL.

 

4.4.3    Worker exposure/risk

Shortly after application it is not necessary to perform any re-entry activities during which intensive contact with the treated crop will occur. Therefore no worker exposure is calculated.

 

4.4.4    Re-entry

See 4.4.3 Worker exposure/risk.

 

Overall conclusion of the exposure/risk assessments of operator, bystander, and worker

The product complies with the Uniform Principles.

 

Operator exposure

For the unprotected operator, adverse health effects after dermal and respiratory exposure to diquat as a result of the application of Mission by mechanical downward spraying on agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop and by manual downward spraying on herbs cannot be excluded. Correct use of personal protective equipment will reduce the dermal and respiratory exposure and results in a sufficient reduction of the exposure to diquat for the application of Mission on agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop.

 

Bystander exposure

Based on the risk assessment, it can be concluded that no adverse health effects are expected for the unprotected bystander due to exposure to diquat during application of Mission in agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop.

 

Worker exposure

Based on the risk assessment, it can be concluded that no adverse health effects are expected for the unprotected worker after dermal and respiratory exposure during re-entry activities in agricultural crops, fruit crops, vegetables, herbs, ornamentals, winter and spring barley, oats, linseed and hop due to exposure to diquat after application of Mission.

 

 

The next sentence has to be placed on the legal instructions:

 “Voor handmatig spuiten van kruiden mag per dag niet meer dan 4000 m2 worden behandeld met Mission”.

 

4.5       Appropriate mammalian toxicology and operator exposure endpoints relating to the product and approved uses

See List of Endpoints.

 

4.6       Data requirements

Based on this evaluation, no additional data requirements are identified.

 

4.7       Combination toxicology

Mission contains only one active substance and it is not described that it should be used in combination with other formulations.

 

4.8       Mammalian toxicology classification and labelling

 

Proposal for the classification of the active ingredient (symbols and R phrases)
(EU classification)

 

Symbol:

T+

Indication of danger: Very toxic

 

Risk phrases

R22

R26

R36/37/38

R43

R48/25

Harmful if swallowed.

Very toxic by inhalation.

Irritating to eyes, respiratory system and skin.

May cause sensitisation by skin contact.

Toxic: danger of serious damage to health by prolonged exposure if swallowed.

 

Proposal for the classification and labelling of the formulation concerning health (Dutch specific aspect)

Based on the profile of the substance, the provided toxicology of the preparation, the characteristics of the co-formulants, the method of application and the risk assessment for the operator, as mentioned above, the following labeling of the preparation is proposed:

Substances, present in the formulation, which should be mentioned on the label by their chemical name (other very toxic, toxic, corrosive or harmful substances):

-

Symbol:

T

Indication of danger:

Toxic

R phrases

R22

Harmful if swallowed.

 

R23

Toxic by inhalation.

 

R36/37/38

Irritating to eyes, respiratory system and skin.

 

R43

May cause sensitisation by skin contact.

 

R48/25

Toxic: danger of serious damage to health by prolonged exposure if swallowed.

S phrases

S35

This material and its container must be disposed of in a safe way.

 

S36/37

Wear suitable protective clothing and gloves.

 

S42b

During spraying wear suitable respiratory equipment (appropriate wording to be specified by the manufacturer).

 

S42j

Wear suitable respiratory equipment during mixing and loading.

 

S45

In case of accident or if you feel unwell, seek medical advice immediately (show the label where possible).

 

Spo2

Wash all protective clothing after use.

Special provisions:
DPD-phrases

-

-

Plant protection products phrase:
DPD-phrase

DPD01

To avoid risk for man and the environment, comply with the instructions for use

Child-resistant fastening obligatory?

Not applicable

Tactile warning of danger obligatory?

Not applicable

 

Explanation:

Hazard symbol:

-

Risk phrases:

-

Safety phrases:

S2, S13, S20 are not obligatory for formulations intended for professional use only.

S21 is not needed based on the assigned R-phrases.

S35 is assigned to preparations with hazard-symbol T+, T, or C with respect to the toxicological aspect of the preparation in question. S39 is not compulsory in combination with the assigned risk-phrases. S42b and S42j are assigned based on the risk assessment for the operator.

SPo2 is assigned by the Ctgb to formulations containing (an) active substance(s) included in Annex I to Reg (EC) 540/2011 labelled with S36/37.

Other:

-

 

 

5.      Residues

 

5.1       Summary of residue data

For the aspect ‘Residues’, and risk for consumers, except for the evaluation of residues in succeeding crops we refer to the member state of the original authorisation (UK).

 

5.1.6        Residues in succeeding crops (Dutch specific aspect)

During the European evaluation it was concluded that residue levels above the LOD (0.01 mg/kg) are not expected in edible fractions of rotational crops. No additional national evaluation is needed.

 

Conclusion

No risk is expected for consumers when authorising Mission according to the intended uses.

 

5.4       Data requirements

-

 

 

6.      Environmental fate and behaviour

 

The underlying risk assessment is based on the final list of endpoints for diquat and on the UK authorisation for Mission. For the Dutch specific aspects data from previous assessment is used.

 

 

List of Endpoints Fate/behaviour 

The LoEP is taken from the final registration report 2001/21/EC OJ L69; dd 10/03/2001

 

Fate and behaviour in soil

 

Route of degradation

 

 

Aerobic:

 

Mineralization after 100 days:

Microbial degradation has been demonstrated only in isolation due to strong adsorption to soil.

Non-extractable residues after 100 days:

Not relevant. See comment above.

Relevant metabolites above 10 % of applied active substance: name and/or code
% of applied rate (range and maximum)

Not relevant. See comment above.

 

 

Supplemental studies

 

Anaerobic:

Relatively stable, withstands degradation

 

 

Soil photolysis:

No significant degradation in 32 d

 

 

Remarks:

Standard requirements are not applicable due to strong adsorption to soil.

 

Rate of degradation

 

 

Laboratory studies

 

DT50lab (20 °C, aerobic):

No measurable degradation in soil under laboratory conditions after one year.

DT90lab (20 °C, aerobic):

Not relevant. See comment above.

DT50lab (10 °C, aerobic):

Not relevant. See comment above.

DT50lab (20 °C, anaerobic):

Not relevant. See comment above.

 

 

Field studies (country or region)

 

DT50f from soil dissipation studies:

DT50 = 10 - 20 y (UK), 1.2 - 3.6 y (US)

DT90f from soil dissipation studies:

DT90 values were never reached

Soil accumulation studies:

Performed as part of US soil dissipation study - refer to detailed results. (16% of diquat applied remained in the soil after 11 years of annual application to the soil at 1 kg diquat/ha/yr)

Soil residue studies:

< 0.05 - 2.3 mg/kg (Denmark 32 sites)

0.11 mg/kg (maximum), 0.03 mg/kg (average) for various Western European Countries

 

Remarks

 

e.g. effect of soil pH on degradation rate

The strong adsorption of diquat to soil precludes diquat degradation in soil being studied effectively by standard guideline methods. The strong adsorption also greatly reduces the rate of formation of degradation products to amounts that would not be detectable using standard methods.

Soil microbial studies fulfil the scientific intent of demonstrating the intrinsic degradability of diquat.

 

 





Adsorption/desorption

 

 

Following end points based on the results obtained from a soil residue study performed at 32 sites in Denmark. (Bewick et al, 1984)

Kf / KOC

Koc values (32 soils in study) ranged from 32,000 to 7,900,000 (very strong adsorption in all the soils tested - with 31 of the soils having Koc values at least one order of magnitude greater than 5,000).

Mean Koc value = 2,184,750

Median Koc value = 1,600,000

Kd

Kd values (32 soils in study) ranged from 1,200 to 92,000 (very strong adsorption in all the soils tested)

Mean Kd value = 27,100

Median Kd value = 23,500

ph dependence

Not relevant

 

 

Mobility

 

Laboratory studies:

 

Column leaching:

Not relevant as all studies indicate that diquat is immobile.

Aged residue leaching:

Not relevant as all studies indicate that diquat is immobile.

 

 

Field studies:

           

Lysimeter/Field leaching studies:

Not relevant as all studies indicate that diquat is immobile.

 

 

 

Remarks:

Adsorption is correlated to clay content.

Adsorption capacity is quantified by wheat

bioasssay (SAC-WB). Most soils have a large

excess in adsorption capacity.

For very sandy soil exceedance may be a possibility following repeated high application

rates.

 

Fate and behaviour in water

 

Abiotic degradation

 

Hydrolytic degradation:

No sterile hydrolysis at environmental pHs.

Relevant metabolites:

None

Photolytic degradation:

DT50 < 7 d (UK summer conditions)

Relevant metabolites:

None

 

 

Biological degradation

 

Ready biological degradability:

 

No, due to rapid adsorption by sediment or
suspended solids.

Water/sediment study:

 

DT50 water:
DT90 water:
DT50 whole system:
DT90 whole system:

Distribution in water / sediment systems
(active substance)

Distribution in water / sediment systems
(metabolites)

 

DT50 = 12 - 24 hours.

 

Aquatic biodegradation studies, (two water/sediment studies performed in the laboratory under aerobic or anaerobic conditions, and a field study performed in natural ponds in the US) show similar results.  The primary route of dissipation of diquat from natural water is through very rapid adsorption onto sediment, or by adsorption onto plant material and/or suspended particulate matter which ultimately settle to the bottom of the pond or water course.  The field study in natural ponds shows that diquat dispersion within and dissipation from water are both extremely rapid with difficulties in measuring these accurately.  Substantial dissipation occurs after a few hours, with estimates of the DT50 for the partition to sediment ranging from  <8 to 34 hours, with a mean of 12 to 24 hours.

Diquat was stable withstanding degradation under the conditions of the aerobic and anerobic studies conducted in pond water and sand sediment.

Accumulation in water and/or sediment:

Not relevant as diquat dissipates very rapidly by adsorption onto sediment; plant material and/or suspended particulate matter which settle to the bottom of the pond or water course.

There is no evidence of desorption of diquat back into the water in the relevant studies.

 

 

Degradation in the saturated zone

See above remarks.

 

 

Remarks:

None

 

Fate and behaviour in air

 

Volatility

 

Vapour pressure:

< 10-8 kPa at 25 °C

Henry's law constant:

5 · 10-12 Pa·m3·mol-1

 

 

Photolytic degradation

 

Direct photolysis in air:

Not relevant, due to low vapour pressure.

Photochemical oxidative degradation in air

DT50:

Not relevant, due to low vapour pressure.

Volatilisation:

Not relevant, due to low vapour pressure.

 

 

Remarks:

None

 

6.1       Fate and behaviour in soil

 

6.1.1        Persistence in soil

The risk assessment of persistence in soil is not a Dutch specific aspect. For the risk assessment we refer to the member state of the original authorization (UK).

 

6.1.2    Leaching to shallow groundwater (Dutch specific aspect)

Leaching to shallow ground water is a Dutch national specific aspect. For the current application for mutual recognition this means that the UK risk assessment for leaching to ground water cannot be used for mutual recognition and a national risk assessment has to be performed.

 

Article 2.9 of the Plant Protection Products and Biocides Regulations (RGB) describes the authorisation criterion leaching to groundwater.

The leaching potential of the active substance (and metabolites) is calculated in the first tier using Pearl 3.3.3 and the FOCUS Kremsmünster scenario. Input variables are the actual worst-case application rate 0.4 kg/ha, the crop potatoes and an interception value appropriate to the crop of 0. Date of yearly application is 25th of April because of application as a pre-emerge herbicide. This application scheme is considered to be worst-case for leaching. The following input data are used for the calculation:

 

PEARL:

 

Active substance:

Geometric mean DT50 for degradation in soil (20°C):  3650 days

Arithmetic mean Kom (pH-independent): 1,267,256 L/kg

Arithmetic mean 1/n: 0.9 (default)

 

Saturated vapour pressure: 1 x 10-5 Pa (25 ºC)

Solubility in water: 718 g/L (20 ºC)

Molecular weight: 184.2 g/mol

 

Other parameters: standard settings of PEARL 3.3.3

 

The following concentrations are predicted for the a.s. diquat following the realistic worst case GAP, see Table M.2.

 

Table M.2 Leaching of a.s. diquat as predicted by PEARL 3.3.3

Use

Substance

Rate substance [kg/ha]

Frequency

Interval [days]

Fraction

intercepted

PEC

groundwater [mg/L]

 

 

 

 

 

 

spring

autumn

Weed control (overall) in:

potatoes, sugar beet, leafy vegetables, pulses, fruiting vegetables, brassicas, root and tuber vegetables, stem vegetables, other vegetables and flower bulbs

diquat

 

0.4

1

-

0

<0.001

<0.001

Weed control (inter rows) in: Agricultural crops (Potatoes, beets, cereals, maize, dry harvested peas, dry harvested beans, dry field beans, grass seed, oilseed, green forage, others) , Fruit crops (Pome fruit, stone fruit, berries and small fruit, strawberries), Vegetables (leafy vegetables, pulses, fruiting vegetables, brassicas, root and tuber vegetables, bulbs, stem vegetebales, other vegetables), herbs (fresh herbs, medical herbs, other herbs) and Ornamentals (flowber bulbs, nursery, forestry, perennials, other ornamentals)

diquat

0.4

1

-

0.2*

<0.001

<0.001

Dessication in:

-Potatoes, winter and spring barley

diquat

0.8

1

-

0.5/0.9

<0.001

<0.001

-dry harvested peas, field beans, oilseed rape, red and white clover, linseed

diquat

0.6

1

-

0.85

<0.001

<0.001

-hop

diquat

0.36

 

 

0.5

<0.001

<0.001

*default fraction intercepted

 

Results of Pearl 3.3.3 using the Kremsmünster scenario are examined against the standard of 0.01 µg/L. This is the standard of 0.1 µg/L with an additional safety factor of 10 for vulnerable groundwater protection areas (NL-specific situation).

 

From Table M.2 it reads that the expected leaching based on the PEARL-model calculations for the a.s. diquat is smaller than 0.01 µg/L for all proposed applications. Hence, the applications meet the standards for leaching as laid down in the RGB.

 

Monitoring data

There are no data available regarding the presence of the substance diquat in groundwater in the Netherlands.

 

Conclusions

The proposed application(s)s of the product comply with the requirements laid down in the RGB concerning persistence in soil and leaching to groundwater.


 

6.2       Fate and behaviour in water

 

6.2.1    Rate and route of degradation in surface water (Dutch specific aspect)

Since the Netherlands has its own national drift values, the exposure concentrations of the active substance diquat in surface water have been estimated for the various proposed uses using calculations of surface water concentrations (in a ditch of 30 cm depth), which originate from spray drift during application of the active substance. The spray drift percen­tage depends on the use. For inter row treatment the use of a protective cover is obligatory as described on label A restriction sentence on the use of aircraft application is part of the label proposed by the applicant. However, aircraft application is not allowed anymore in the Netherlands from November 2011 onwards. Hence this restriction is no longer needed on the label, since it is covered by law. This sentence has already been removed in the conversion of the directions for use (WGGA) in the Legal Conditions for Use (WG) of plant protection products.

Concentrations in surface water are calculated using the model TOXSWA. The following input data are used for the calculation:

 

TOXSWA:

Active substance:

Mean DT50 for degradation in water at 20°C:  1000 days* (no degradation in the total system)

DT50 for degradation in sediment at 20°C: 1000 days (default).

 

Arithmetic mean Kom for suspended organic matter: 1,267,256 L/kg

Arithmetic mean Kom for sediment: 1,267,256 L/kg

 

Saturated vapour pressure: 1 x 10-5 Pa (25 ºC)

Solubility in water: 718 g/L (20 ºC)

Molecular weight: 184.2 g/mol

 

Other parameters: standard settings TOXSWA

* diquat dissipated to the sediment quickly (DisT50 1 day), no degradation was demonstrated

 

When no separate degradation half-lives (DegT50 values) are available for the water and sediment compartment (accepted level P-II values), the system degradation half-life (DegT50-system, level P-I) is used as input for the degrading compartment and a default value of 1000 days is to be used for the compartment in which no degradation is assumed. This is in line with the recommendations in the FOCUS Guidance Document on Degradation Kinetics.

 

In Table M.3a, the drift percentages and calculated surface water concentrations for the active substance diquat for each intended use are presented.

 

Table M.3a Overview of surface water concentrations for active substance and metabolite(s) following spring and autumn application

No/ Use

Substance

Rate a.s.

[kg/ha]

Freq.

Drift

[%]

PIEC

[mg/L] *

PEC21

[mg/L] *

PEC28

[mg/L] *

 

 

 

 

 

Spring

autumn

spring

autumn

spring

autumn

1

Weed control (overall/inter rows) in:

potatoes, sugar beet, leafy vegetables, pulses, fruiting vegetables, brassicas, root and tuber vegetables, stem vegetables, other vegetables and flower bulbs

0.4

1

1

0.194

0.194

0.16

0.027

0.15

0.020

 

Dessication in:

-Potatoes, winter and spring barley

0.8

1

1

0.41

0.41

0.34

0.06

0.31

0.04

 

-dry harvested peas, field beans, oilseed rape, red and white clover, linseed

0.6

1

1

0.30

0.30

0.25

0.04

0.23

0.03

 

-hop

0.36

1

2.7**

0.513

0.513

0.415

0.07

0.382

0.05

* calculated according to TOXSWA

** drift percentage for spraying of lane tranes “opzetters” (widely spaced) used for hop.

 

PECsediment

To address the risk to sediment organisms, a PEC sediment value is needed for diquat

The PECsediment values calculated with TOXSWA are expressed in g a.s./m3 sediment. This PECsed has to be converted to mg a.s./kg sed dw by dividing it by the dry bulk density.

It is assumed that the substance will be present mainly in the top 1 cm layer. This layer has a density of 80 kg/m3. The maximum PEC value in sediment in the top 1 cm of sediment is reached at day 28 after application. See Table M.3b for calculation of PECsediment.

 

Table M.3b Maximum sediment concentration for active substance diquat following spring application (worst-case)

Use

Substance

Rate a.s.

[kg/ha]

drift

[%]

PECsediment

[g a.s./m3 sediment] *

PECsediment

[mg a.s./kg sediment dw]**

 

 

 

 

spring

spring

Hop

diquat

0.36

2.7***

0.789E-2

0.10

* TOXSWA output 

** calculated as (PECsed in g/m3 / 80 kg/m3)*1000 (conversion of g/kg to mg/kg)

*** drift percentage for spraying of lane tranes “opzetters” (widely spaced) used for hop.

 

The exposure concentrations in surface water are compared to the ecotoxicological threshold values in section 7.2.

 

Monitoring data

The Pesticide Atlas on internet (www.pesticidesatlas.nl, www.bestrijdingsmiddelenatlas.nl) is used to evaluate measured concentrations of pesticides in Dutch surface water, and to assess whether the observed concentrations exceed threshold values.

Dutch water boards have a well-established programme for monitoring pesticide contamination of surface waters. In the Pesticide Atlas, these monitoring data are processed into a graphic format accessible on-line and aiming to provide an insight into measured pesticide contamination of Dutch surface waters against environmental standards.

Recently, the new version 2.0 was released. This new version of the Pesticide Atlas does not contain the land use correlation analysis needed to draw relevant conclusions for the authorisation procedure. Instead a link to the land use analysis performed in version 1.0 is made, in which the analysis is made on the basis of data aggregation based on grid cells of either 5 x 5 km or 1 x 1 km.

 

Data from the Pesticide Atlas are used to evaluate potential exceeding of the authorisation threshold and the MPC (ad-hoc or according to INS) threshold.

For examination against the drinking water criterion, another database (VEWIN) is used, since the drinking water criterion is only examined at drinking water abstraction points. For the assessment of the proposed applications regarding the drinking water criterion, see next section.

Diquat

The active substance diquat was observed in the surface water (most recent data from 2007). In Table M.4 the number of observations in the surface water are presented.

In the Pesticide Atlas, surface water concentrations are compared to the authorisation threshold value of  0.84µg/L ((23/01/2006), consisting of first or higher tier acute or chronic ecotoxicological threshold value, including relevant safety factors, which is used for risk assessment, in this case 0.1*NOEC for Lemna) and to the indicative Maximum Permissible Concentration (MPC) of 1 µg/L as presented in the Pesticide Atlas

 

Currently, this MPC value is not harmonised, which means that not all available ecotoxicological data for this substance are included in the threshold value. In the near future and in the framework of the Water Framework Directive, new quality criteria will be developed which will include both MPC data as well as authorisation data.

The currently available MPC value is reported here for information purposes. Pending this policy development (finalisation for all substances expected in 2009-2010), however, no consequences can be drawn for the proposed application(s).

At the time of the first assessment of Mission the following data were available:

 

Table M.4 Monitoring data in Dutch surface water (from www.pesticidesatlas.nl, version 2.0)

Total no of locations

(year 2007)

n > authorisation threshold

 

n > indicative/ad hoc MPC threshold

 

n > MPC-INS threshold *

24 locations **, 1

0

0

n.a.

* n.a.: no MPC-INS available. < : exceeding expected to be lower than with 4th Document MPC value; > : exceeding expected to be higher than with 4th Document MPC value

** the number of observations at each location varies between 4 and 10, total number of measurements is 96 in 2007.

1 sum of reportings on diquat and diquatdibromide

 

The correlation of exceedings with land use is derived from the 1.0 version of the Pesticide Atlas. Hence, the correlation is not based on the exact same monitoring data. However, this is the best available information and therefore it is used in this assessment.

As there are no exceedings no consequences can be drawn from the observed measurements with regard to the proposed an already authorised uses.

 

Drinking water criterion

Assessment of the drinking water criterion is in principle not a Dutch national specific aspect however the interpretation is done in a Dutch specific way.

 

It follows from the decision of the Court of Appeal on Trade and Industry of 19 August 2005 (Awb 04/37 (General Administrative Law Act)) that when considering an application, the Ctgb should, on the basis of the scientific and technical knowledge and taking into account the data submitted with the application, also judge the application according to the drinking water criterion ‘surface water intended for drinking water production’. No mathematical model for this aspect is available. This means that any data that is available cannot be adequately taken into account. It is therefore not possible to arrive at a scientifically well-founded assessment according to this criterion. The Ctgb has not been given the instruments for testing surface water from which drinking water is produced according to the drinking water criterion. In order to comply with the Court’s decision, however - from which it can be concluded that the Ctgb should make an effort to give an opinion on this point – and as provisional measure, to avoid a situation where no authorisation at all can be granted during the development of a model generation of the data necessary, the Ctgb has investigated whether the product under consideration and the active substance could give cause for concern about the drinking water criterion.

 

Diquat has been on the Dutch market for > 3 years (authorised since before 1994). This period is sufficiently large to consider the market share to be established. From the general scientific knowledge collected by the Ctgb about the product and its active substance, the Ctgb concludes that there are in this case no concrete indications for concern about the consequences of this product for surface water from which drinking water is produced, when used in compliance with the directions for use. The Ctgb does under this approach expect no exceeding of the drinking water criterion. The standards for surface water destined for the production of drinking water as laid down in the RGB are met.

 

Conclusion drinking water criterion

The original registration in UK was not assessed against the drinking water criterion.

Conclusion risk assessment according to RGB: all proposed applications of the product comply with the RGB.

 

 

6.3       Fate and behaviour in air

 

Route and rate of degradation in air

Assessment of fate and behaviour in air is not a Dutch national specific aspect. For the current application for mutual recognition this means that the UK risk assessment should be used. At present there is no framework to assess fate and behaviour in air of plant protection products.

 

6.4       Appropriate fate and behaviour end-points relating to the product and approved uses

See List of End-points.

 

6.5       Data requirements

None.

 

The following restriction sentences were proposed by the applicant:

Het is verboden dit middel met een luchtvaartuig toe te passen. N.B. This sentence has been removed in the conversion of the directions for use (WGGA) in the Legal Conditions for Use (WG) of plant protection products.

 

Based on the current assessment, the following has to be stated in the GAP/legal instructions for use:

None.

 

6.6       Overall conclusions fate and behaviour

It can be concluded that:

  1. all proposed applications of the active substance diquat meet the standards for leaching to the shallow groundwater as laid down in the RGB.
  2. UK did not assess the product with regard to the standards for surface water destined for the production of drinking water, however, the proposed applications of the product comply with the RGB with regard to the standards for surface water destined for the production of drinking water.

 

 

7.      Ecotoxicology

 

The underlying risk assessment is based on the final list of endpoints for diquat and on the UK authorization of Mission.

 

List of Endpoints Ecotoxicology

Diquat is placed on Annex I since 2002. For the risk assessment the LoEP from the final conclusion (03/2001) is used.

 

Ecotoxicology

Terrestrial Vertebrates

Acute toxicity to birds:

LD50 = 83 mg /kg bw (diquat ion)

Anas platyrhynchos

Dietary toxicity to birds:

LC50 = 721 ppm, 5 d study (diquat ion)

Coturnix japonica (162 mg a.s./kg bw/d, recalculated by applicant)

Reproductive toxicity to birds:

NOEC = 5 mg/kg (diquat ion) (= 0.6 mg a.s./kg bw/d based on FIR/bw 0.121 1)

 

 

28 d NOEC = 100 ppm = 21.7 mg a.s./kg bw/d  (Mallard ducklings, 1 d old) 2

 

9 w NOEC = 40 ppm = 6.6 mg a.s./kg bw/d (Mallard duck) a

 

12 w NOEC = <80 ppm (Mallard duck), quick recovery – see discussion below2

1 based on FIR/bw = (146/1205 =) 0.121 (data provided by notifier)

2 evaluated in RIVM-report 12465A00

 

Relevant long-term toxicity value

(Statement provided by the notifier for their own product; and repeated by the applicant. The applicant has a LoA from the notifier for the essential studies)

The above risk assessment is based on the lowest reproduction NOEC given in the LoE. However, more reproduction studies were done. Below an overview is given of the available chronic bird studies with a.s. diquat.

 

Long-term toxicity of diquat to birds

Study type

Species

Endpoint

Value (expressed as diquat ion)

Reference

Studies submitted during EU Peer Review:

Effects on reproduction
(18 weeks  exposure)

Colinus virginianus (Bobwhite quail)

NOEC

(NOEL)

100 mg/kg diet

(9.4 mg/kg bw/d)

Beavers and Fink, 1982b

Effects on reproduction

(18 weeks exposure, including poor layers)

Anas platyrhynchos (Mallard duck)

5 mg/kg diet according to LoE (0.6 mg/ a.s.kg bw/d1 )

 

Beavers and Fink, 1982c

Effects on duckling growth
(2 and 4 weeks  exposure)

 

Anas platyrhynchos (Mallard duck)

NOEC

(NOEL)

100 mg/kg diet

(21.7 mg/kg bw/day)

Frey et al., 1995

New studies, submitted to Ctgb after EU Peer Review:

Effect on reproduction

(3 weeks pre-egg laying plus 6 weeks post-egg laying exposure, including poor layers)

Only egg production and egg weight measured

Anas platyrhynchos (Mallard duck)

NOEC

(NOEL)

40 mg/kg diet

(6.6 mg/kg bw/day for males + females; 10.0 mg/kg bw/d for females only)

 

Temple et al., 2004a
PP901/1436

Effect on reproduction

(6 weeks post-egg laying exposure, normal layers)

Only egg production and egg weight measured

Anas platyrhynchos (Mallard duck)

80 mg/kg diet

(11.1 mg/kg bw/day)

 

 

Temple et al., 2004b
PP901/1437 

Effect on reproduction

(6 weeks post-egg laying exposure, late layers)

Only egg production and egg weight measured

Anas platyrhynchos (Mallard duck)

>20 mg/kg diet

(2.7 mg/kg bw/day)

Reproduction Study to Evaluate Reversibilty oin Effects

(6 weeks exposure during egg laying, and 6 weeks recovery)

Anas platyrhynchos (Mallard duck)

LOEC = 80 mg/kg diet (11.1 mg/kg bw/day), but complete recovery seen after 1 week at this rate.

Recovery seen after 2 weeks at 160 mg/kg diet (19.7 mg/kg bw/day)

Temple  et al., 2009
(PP901/10751)

1 based on FIR/bw = (146/1205 =) 0.121 (data provided by notifier)

 

Besides these studies in which the effects of diquat on birds were studied, the applicant also performed a feeding regime study without active substance (Temple, 2006). The purpose of this study was to investigate the differences in food consumption between male and female mallard ducks and to consider how this might affect the estimate of the LOEL and NOEL for sex specific endpoints. This study demonstrates that following the onset of egg-laying, female exposure may double through increased food consumption, while in the male it remains relatively constant. Thus the NOED based on the daily dose per bird for female specific endpoints tends to be underestimated when the calculation from the NOEL to the NOED is based on the mean feed consumption for both sexes.

Based on this study, female feed consumption can be calculated as follows:

Female feed consumption at plateau = Feedweek1 + 2 * (Feedweek5-9 -Feedweek1)

This approach can be considered as a generic method for calculating female feed consumption and therefore be applied to mallard reproduction studies, unless food avoidance behaviour is noticed. 

Based on the above formula, the NOEC of 40 ppm from the Temple & Martin study of 2004a is recalculated to 10 mg a.s./kg bw/d for females only.

 

The lowest available NOEC is 5 mg/kg diet, which is equivalent to a NOEL of 0.6 mg/kg bw/d, based on effects on the number of viable embryo’s, the number of live 3 weeks embryo’s, the number of hatchlings and the number of 14 day old survivors (Fink&Beavers, 1982b). These parameters were also measured in the new study by Temple et al. of 2009 and they were found not to be affected at 80 and 160 ppm. The Temple study is considered more relevant in exposure duration (diquat is applied only once per season and availability for birds is expected to be much shorter than the 18 weeks exposure used in the old study) and furthermore of better quality (higher statistical power because more replicates were used). Therefore, it is considered that the EU-endpoint of 0.6 mg a.s./kg bw/d based on the Fink & Beavers study of 1982b can be superseded. The relevant endpoints for use in the egg-laying period are the NOEL of 10 mg a.s./kg bw/d for mallard duck and 9.4 mg as/kg bw/d for bobwhite quail (the underlaying studies are based on exposure of parents (and eggs) in the egg-laying period). Thus, the NOEL to be used for risk assessment of Reglone applications during the egg-laying season is 9.4 mg a.s./kg bw/d.

 

The Temple et al. study of 2009 was furthermore initiated to give an answer to the question whether outside the breeding period a NOEC of 21.7 mg/kg bw/d for adult birds could be used instead of a NOEC of 9.4 mg/kg bw/d which is the applicable NOEC for the reproductive phase of the birds.

Clinical observations of adults did not show overt signs of toxicity and gross pathology did not show treatment related abnormalities. Feed consumption was significantly reduced during week 1 in the 80 mg diquat cation per kg food (~ 11.1 mg/kg bw/d) but not in the 5 following weeks of exposure. Feed consumption was significantly reduced during week 1, 3, 4, 5 and 6 in the 160 mg diquat cation per kg food (~ 19.7 mg/kg bw/d). Feed consumption after the exposure period was comparable to the control group.

No significant changes in body weight were noticed in any of the two exposure levels.

There was a marked reduction of number of eggs laid during the 6 weeks exposure period in both treatment groups. During the withdrawal phase the 80 mg diquat per kg food treatment group (11.1 mg/kg bw/d) recovered quickly. Egg production in the 160 mg diquat per kg food treatment group (19.7 mg/kg bw/d) remained depressed in the first week of the withdrawal phase, increased during the second week and was comparable to the control during the third and following weeks of the experiment. No other reproductive effects were noticed. If the application of Reglone is during the egg-laying season, the NOEL of 10 mg as/kg bw/d can be used for mallard. For quail a slightly lower NOEL of 9.4 mg as/kg bw/d is available. Therefore, the relevant endpoint during the egg-laying season is 9.4 mg as/kg bw/d.

From the Temple et al. study of 2009 it could be concluded that the use of diquat will not influence the breeding success in the following breeding period. It is evident that birds do not like diquat and probably will look for other types of food. No other effects have been noticed that are relevant for the survival of birds outside the breeding period. Therefore, if the application of Reglone is outside the egg-laying season, the NOEL for duckling development can be used, which is 21.7 mg/kg bw/d based on the Frey et al study from 1995. 

 

Aquatic Organisms

Acute toxicity fish:

LC50 = 21 mg /l, 96 h static study (diquat ion)

Oncorhynchus mykiss

LC50 = 6.1 mg /l, 96 h flow through study (diquat ion)

Oncorhynchus mykiss

Long term toxicity fish:

Pimephales promelas 34 day study on embryos/larvae - NOEC (larval weight) considered to be 0.12 mg diquat/litre based on mean measured concentration

Bioaccumulation fish:

Low risk of bioaccumulation

Acute toxicity invertebrate:

EC50 = 1.2 mg/l, 48 h study Daphnia magna (diquat ion)

Chronic toxicity invertebrate:

21‑day LC50 was 0.16 mg/l based on nominal concentration Daphnia magna (diquat ion).  21-day NOEC = 0.125 mg/l based on nominal concentration.

Acute toxicity algae:

EC50 = 0.011 - 1.0 mg/l, 96 h study (diquat ion)

Psuedokirchneriella subcapitata (syn. Rhapidocellis subcapitata and Selenastrum capricornutum)

Acute toxicity algae - study in presence of sediment

NOEC biomass = 320 mg/l with EbC50 of >320 mg/l.  72 hours (diquat ion)..

NOEC growth rate = 320 mg/l with ErC50 of >320 mg/l.  72 hours (diquat ion).

Psuedokirchneriella subcapitata (syn. Rhapidocellis subcapitata and Selenastrum capricornutum)

Chronic toxicity sediment dwelling organism:

NOEC > 100 mg diquat ion/kg-1 sediment (diquat ion).

Chironomus riparius

Acute toxicity aquatic plants:

No data requirement set at time of review.

 

Honeybees

Acute oral toxicity:

LD50 = 13 µg /bee (diquat ion)

Acute contact toxicity:

LD50 = 60 µg /bee (diquat ion)

 

Other arthropod species

Test species

% Effect

Aphidius rhopalosiphi

An extended laboratory study. At full field rate (i.e. 5 l/ha) there was significant mortality of wasps in the treatment compared to the control.  No adverse effects were noted on either fecundity or behaviour.

 

 

Coccinella septumpunctata.

Extended laboratory study. Bean plants treated with ‘Reglone’ at 5 l/ha (1000 g /ha) - equivalent to the maximum field rate.

Larvae of Coccinella septumpunctata exposed to residues of the test substance. 

Corrected pre-imaginal mortality of Coccinella septumpunctata was 58%, mortality for the positive control was 78.9%.

The reproduction rate was:

·       640.9 eggs/female in the treatment

·       255.3 eggs/female in the control.

R value 151.0%.

Results within the range of historical control variability.

IOBC classification : slightly harmful

Trichogramma cacocecie

Laboratory study: exposed to 'Reglone' at 1000 g diquat ion/ha - equivalent to maximum field rate.

Parisitisation capacity reduced by 58 %.

Exposed adults reduced by 98%.

Chrysoperla carnea

Laboratory study: exposed to 'Reglone' at 1600 g diquat ion/ha.

96% mortality recorded in exposed larvae.

 

Pterosticus melanarius

Exposed to 'Reglone' at 1600g diquat ion/ha on loamy sand.

No lethal or sublethal effects.

Pardosa spp.

Exposed to 'Reglone' at 1600g diquat ion/ha on loamy sand.

No lethal or sublethal effects.

 

Earthworms

Acute toxicity:

 

LC50 = 130 mg as/kg soil 14 day (diquat ion)

NOEC > 18 mg as/kg soil 14 day (diquat ion)

 

Soil micro-organisms

Nitrogen mineralization:

No significant effects up to  50.0 kg diquat/ha

Carbon mineralization:

No significant effects up to 720 kg as/ha

 

Mission (200 g/L diquat)

Additional studies were summarized and evaluated by EPP consultancy (report 120603, 06/2012).

 

Aquatic Organisms

Acute toxicity aquatic plants (Lemna minor):

7-d ErC50 357 µg form*./L (62.5 µg a.s./L)

7-d EbC50 173µg form./L (30.2 µg a.s./L)

7-d NOEr,bC 33.7 µg form./L (5.9 µg a.s./L)

* SL formulation containing 203.5 g diquat/L (174.9 g diquat/kg)

 

Other arthropod species

Test species

Organism stage/Type of test

Value/ Adverse effect

Typhlodromus pyri

Protonymphs 2-3 days old/Dried residues on sprayed sweet-pepper leaves

Mortality: LR50 23.4 mL form*./ha (4.75 g a.s./ha)

Reproduction: ER50 >64.0 mL form./ha (>13.0 g a.s./ha)

Chrysoperla carnea

Larvae 2-4 days old/Dried residues on sprayed bean plants

Mortality: LR50 4.46 L form./ha (0.90 kg a.s./ha)

Reproduction (viable eggs/female/d):

2.0 L form./ha (0.41 kg a.s./ha) +16%**

4.0 L form/ha  (0.81 kg a.s./ha) 18%

 

* SL formulation containing 202.9 g diquat/L

** + means increase compared to control

 

Earthworms

Reproduction toxicity (Eisenia fetida):

NOEC 248 mg form./kg dw (43.3 mg a.s./kg dw)

 

Other soil non-target macro-organisms

Reproduction toxicity (Folsomia candida):

Mortality:

LR50 29.1 mg form./kg dw (5.08 mg a.s./kg dw)

 

Reproduction:

EC50 20.4 mg form./kg dw (3.56 mg a.s./kg dw)

NOEC 5.6 mg form./kg dw (0.98 mg a.s./kg dw)

 

Effects on non-target plants

Test substance

Test type

Species

Endpoint

 

Value

Diquat 200 g/L SL*

Vegetative vigour

Zea mays

 

 

Allium cepa

 

 

Beta vulgaris

 

 

Brassica napus

 

 

Daucus carota

 

 

Glycine max

 

21-d NOER

21-d ER50

 

21-d NOER

21-d ER50

 

21-d NOER

21-d ER50

 

21-d NOER

21-d ER50

 

21-d NOER

21-d ER50

 

21-d NOER

21-d ER50

<0.0512 L form./ha

1.16 L form./ha

 

0.32 L form./ha

1.94 L form./ha

 

0.0102 L form./ha

0.153 L form./ha

 

<0.0512 L form./ha

0.242 L form./ha

 

0.0512 L form./ha

0.240 L form./ha

 

0.128 L form./ha

0.512 L form./ha

* SL formulation containing 202.9 g diquat/L

 

Based on the results of the vegetative vigour, the applicant has submitted a resulted HC5 of 0.081154 L form/ha calculated using ETX 2.0. 

 

The applicant has submitted a letter report on “ Assessment of the effect of Diquat 200 g/L SL on the emergence of non-target terrestrial plants” . This is a screening test performed with doses of 4-36 L formulation/ha in 9 plant species: Allium cepa, Avena sativa, Brassica napus, Linum usitatissium, Helianthus annuus, Lycopersicon esculentum, Pisum sp., Daucus carota subsp. Sativus, Lactuca sativa. In this letter it was concluded that at doses up to 36 L form/ha the emergence and plant weights are not affected. The report was not evaluated for reliability by Ctgb.

 

 

Additional studies                                                              

 

Measured residues of diquat in a Canadian field study (for bird and mammal risk assessment) (evaluated in RIVM-report 11162A00, also available in EU-monograph (Edwards et al. 1991))

 

A study has been conducted in Canada to assess the potential effect of accidental overspray application on plant cover (bird nesting habitat) and on exposure to residues on their food. Six sites, each comprising a field, slough (prairie pond) and upland, were deliberately sprayed with diquat both on- and off-crop from the air at a rate of 550 g diquat/ha in July and August. Resulting residue values and residue degradation are shown in the Table below.

 

Diet

n=

Initial residue value, 90thile or max, at 0.55 kg/ha

(mg/kg fresh weight)

Initial residue value, 90thile or max, RUD for 1.0 kg/ha

(mg/kg fresh weight)

Initial mean residue value at 0.55 kg/ha

(mg/kg fresh weight)

Initial mean residue value, RUD at 1.0 kg/ha

(mg/kg fresh weight)

DT50 value

(days)

21-day TWA residue

(mg/kg)

ftwa

r2

Ric

Terrestrial vegetation

12

60.3 (90th percentile)a

110

36.8

66.9

1.59

4.07

0.11

0.85

1

Terrestrial invertebrates (pitfall traps)

2

6.9 (maximum) a

12.5

4.80

8.73

1.23

0.40

0.084

0.76

1

Whole seeds

5

42 (maximum) a

76

22

40

13.4

14.2

0.61

0.15

3

Seeds without husk

5

64 (maximum) a

116

21

38

13.7

9.44

0.62

0.16

3

Crop seed

nd

ndb

 

0.521

ndb

4.62

0.155

0.31

0.24

3

Aquatic vegetation

nd

ndb

 

5.23

ndb

2.96

1.06

0.20

0.20

3

Aquatic invertebrates

nd

ndb

 

1.61

ndb

1.58

0.11

0.068

0.56

3

Aquatic tubers

nd

ndb

 

0.583

ndb

7.53

0.256

0.45

0.50

3

Aquatic seeds

nd

ndb

 

1.07

ndb

17.5

0.625

0.68

0.16

3

a According to SANCO/4145/2000, 90th percentile residue values can be used for acute risk assessment. However, this is only acceptable when the sample size is sufficiently large. In this case, maximum values are given when n<10 and 90th percentile values when n≥10.

b Not given, because not relevant for the risk assessment.

c Ri = Risk index. Ri  1: acceptable; Ri 3: not acceptable. Ri values refer only to degradation, not to initial values.

 

Remarks:

The study is considered relevant for spray application of diquat in the Netherlands.

All initial residue values can be used for risk assessment. The recalculated DT50 values, 21-day TWA residues and ftwa for terrestrial vegetation and invertebrates can also be used for long-term risk assessment. For the other feed substances the fit was not good enough resulting in unreliable DT50 values, 21-day TWA and ftwa (Ri = 3).

 

The residue data from the Canadian field study are based on invertebrates sampled with pitfall traps. Thus, foliar dwelling invertebrates are not included, whilst it cannot be excluded that these will be exposed as well, and may be exposed to a higher degree because no crop interception takes place. However, two field studies with paraquat in which residues on invertebrates were measured after application of 1.1 kg paraquat/ha in an apple orchard and melon field in Spain (Bakker (2004 and 2005), evaluated in RIVM-report 10994A01), show a mean (over different invertebrate groups) maximum (in time) residue value of 6.43 mg a/s/kg for foliar dwelling/flying invertebrates. Considering the similarities in physico-chemical and fate/behaviour properties of paraquat and diquat, which makes a comparison of residue data acceptable, it can be concluded that the RUD value of 8.73 mg a.s./kg for diquat based on pitfall samples only, is not likely to result in an underestimation of exposure, and is therefore acceptable.   

 

7.1       Effects on birds

The risk assessment for birds via sprayed food (via natural food and secondary poisoning via earthworms) is not a Dutch specific aspect. For the current application for mutual recognition this means that the UK risk assessment should be used.

 

However, it is known that diquat can cause problems in birds (evaluation of Reglone, C164.3.8, 01/2006). A refined risk assessment was required.

In a later stage, from protected studies in birds, it was shown that diquat can cause problems in the egg-laying period (evaluation of Reglone, C187.3.14, 11/2007). This has lead to a discussion about the egg-laying period for birds. In C187.3.14 the following was concluded for the Reglone applications:

 

‘However: in a letter from the Dutch Ministry of Agriculture, Nature and Food quality (LNV) d.d. 23-11-2007, further directions were given. In this letter it is stated that the desiccation use in potatoes after the 15th of July can be considered to take place outside the main breeding season for birds. Therefore, the ministry sees no objection in the extension of the authorisation of the desiccation use of Reglone in potatoes, under the condition that application takes place after the 15th of July and that within 2 years the applicant should demonstrate that no unacceptable effects for birds will result from this application after 15 July.

 

Based on the above, the standards for birds are met for the desiccation use of Reglone in potatoes, under the condition that the application takes place after the 15th of July and that within 2 years the applicant has to demonstrate that no unacceptable effects for birds will result from this application after 15 July.’

 

In a later stage, applicant submitted new protected studies which showed that the restriction of using Reglone as a desiccant in potatoes after 15 July could was no longer necessary (evaluation of Reglone, C216-3.10, 28 April 2010). Agrichem has access to the most relevant ones of these studies.

 

All other defended crops were removed from the label because of the unacceptable risk for several aspects, including birds and mammals.

 

To indicate the risk for Mission, a short, indicative first tier risk assessment (only the most relevant aspects are included) is given below. :

 

Indicative risk assessment birds (first tier)

Birds can be exposed to the active substance diquat via natural food (sprayed insects, seeds, leafs.

 

The threshold value for birds is based on the trigger from the RGB. This means that Toxicity-Exposure Ratio’s (TERs) for acute and short-term exposure should be ³ 10 and TER for chronic exposure should be ³ 5.

Table E.1 presents an overview of toxicity data.

 

Table E.1 Overview of toxicity data for birds for substance Diquat

 

Endpoint

Value

Acute toxicity to birds:

LD50

83 mg a.s./kg bw

Reproductive toxicity to birds:

NOEL

5 ppm mg a.s./kg bw/d = 0.6 mg/kg bw/d

 

7.1.1    Natural food and drinking water

 

Sprayed products

Procedures for risk assessment for birds comply with the recommendations in the Guidance Document on Risk Assessment for Birds and Mammals under Council Directive 91/414/EEC (Sanco/4145/2000).

For the current application, uses can be categorized as leafy crops. Depending on the crop category, different indicator species are chosen. Table E.2  shows which indicator species are relevant for which uses.

 

Table E.2 Indicator species per use

Use

Crop

Indicator species

Hop (best case)

Leafy crops

medium herbivorous and insectivorous

Potatoes, cereals (worst-case)

Leafy crops

medium herbivorous and insectivorous

 

Table E.3a-b show the TER values for birds. The estimated daily uptake values (ETE, Estimated Theoretical Exposure) for acute, short-term and long-term exposure are calculated using the Food Intake Rate of the indicator species (FIR) divided by the body weight of the indicator species (bw), the Residue per Unit Dose (RUD), a time-weighted-average factor (fTWA, only for long term) and the application rate. For uses with frequency > 1, a MAF (Multiple Application Factor) may be applicable. The ETE is calculated as application rate * (FIR/bw) * RUD * MAF [* fTWA, only for long term]. The ETE is compared to the relevant toxicity figure. TER should be above the trigger for an acceptable risk.

 

Table E.3a Acute risk for birds

use

FIR / bw

RUD

Applica-tion rate

 

(kg a.s./ha)

MAF

Acute-term ETE

LD50 (mg/kg bw/d)

TER

Threshold exceeding level

(mg/kg bw/d)

(trigger 10)

 

medium herbivorous bird

hop

0.76

87

0.36

-

23.8

83

3.49

2.87

Potatoes & cereals

0.76

87

0.8

-

52.9

83

1.57

6.37

insectivorous bird

 

 

 

 

 

 

hop

1.04

52

0.36

 

18.9

83

4.39

2.28

Potatoes & cereals

1.04

52

0.8

 

43.3

83

1.92

5.21

 

Table E.3b Long-term risk for birds (with refined RUD and Ftwa from the new guidance document)

use

FIR / bw

RUD

Applica-tion rate

 

(kg a.s./ha)

MAF

ftwa

Long-term ETE

NOEL (mg/kg bw/d)

TER

Threshold exceeding level

 

(mg/kg bw/d)

(trigger 5)

 

medium herbivorous bird

hop

0.76

40

0.36

 

0.53

5.80

0.6

0.10

50

Potatoes & cereals

0.76

40

0.80

 

0.53

12.9

0.6

0.047

106

insectivorous bird

hop

1.04

21

0.36

 

0.53

4.17

0.6

0.14

35.7

Potatoes & cereals

1.04

21

0.8

 

0.53

9.26

0.6

0.065

76.9

 

Based on the results presented in the tables above, a high risk is expected.

 

Refined risk assessment

As the former problems with birds are solved in the Reglone Dossier (C216-3.10; April 2010) for the application as a desiccant in potatoes; the reason for not accepting the Mutual recognition for this use is not valid anymore. Therefore for the use as desiccant in potatoes, a reference is made to the UK assessment. After consultation with the applicant, the uses in orchards, cereals, hops and several others are withdrawn by applicant and removed from the label. For the other uses on the label, a further refinement is performed below

 

Relevant endpoints

For the chronic risk, the applicant has a LoA for the additional studies from Syngenta. The applicant proposes to use the NOEC of 9.4 kg/kg bw/d based on the new studies, also for the risk outside the breeding season, for which a NOEC of 21.7 mg a.s./kg /d was previously accepted. According to EFSA 2009, the risk assessment should be performed either with the lowest from the relevant chronic endpoints or the LC50/10, which is 11.5 mg/kg bw/d. Since the lowest NOEC for the reproduction studies is below this value, namely 9.4 mg/kg bw/d, this value will be used in risk assessment , as proposed by the applicant.

 

Residue data

Residue data on insects is available. The max residue value found was 6.9, corresponding to a max RUD of 12.5. These values can be used in the acute risk assessment.

In the chronic risk assessment, the mean RUD of 8.73 mg/kg as well as the DT50 of 1.23 days can be used for the refinement of the insectivorous component and the mean RUD of 66.9 mg/kg as well as the DT50 of 1.59 days can be used for the refinement of the herbivorous component.

 

Interception

As potatoes are not palatable for birds, the risk to herbivores is performed via exposure via weeds. As potatoes in the later growth stages cover the soil almost completely, interception via potato leaves in relevant.

 

 

 

 

 

 

Refined risk assessment

 

Table E.3c Acute risk for birds

use

FIR / bw

RUD

Application rate

 

(kg a.s./ha)

MAF

DF

Acute-term ETE

LD50 (mg/kg bw/d)

TER

 

(mg/kg bw/d)

(trigger 10)

Medium herbivorous bird

 

 

 

 

 

Early post-emergence in several crops

0.76

87

0.4

-

-

26.4

83

3.12

Beans & clover (dessication)

0.76

87

0.6

-

-

39.7

83

2.09

insectivorous bird

 

 

 

 

 

 

 

Bare soil & early post- emergence in several crops

1.04

12.5

0.4

 

 

5.2

83

16.0

Beans & clover (desiccation)

1.04

12.5

0.6

 

 

7.8

83

10.6

 

Table E.3d Long-term risk for birds (with refined RUD and Ftwa from the new guidance document)

use

FIR / bw

RUD

Applica-tion rate

 

(kg a.s./ha)

MAF

ftwa

DF

Long-term ETE

NOEL (mg/kg bw/d)

TER

 

 

(mg/kg bw/d)

(trigger 5)

Medium herbivorous bird

 

 

 

 

 

 

 

 

 

Early post-emergence in several crops

0.76

67

0.4

 

0.11

 

2.24

9.4

4.2

Beans & clover (desiccation)

0.76

67

0.6

 

0.11

 

3.36

9.4

2.80

insectivorous bird

 

 

 

 

 

 

 

 

 

Bare soil & early post- emergence in several crops

1.04

8.73

0.4

 

0.085

 

0.31

9.4

29.6

Beans & clover (desiccation)

1.04

8.73

0.6

 

0.085

 

0.46

9.4

20.3

 

 

Based on the calculations presented above, an acute risk cannot be excluded for all proposed uses, except for the bare soil uses. A chronic risk is acceptable for the bare soil applications.

 

Acute risk assessment according to EFSA (2009)

 

A further refinement is presented according to EFSA 2009.

 

According to the GD (EFSA 2009) it is recommended to calculate a geometric mean if acute toxicity studies from more than one species are available. The geometric mean from the available studies is 115 mg a.s./kg, which will be used for the acute risk assessment.

 

Table E4a Acute risk assessment for birds -  screening step and first-tier assessment, using geometric mean LC50 of 115 mg a.s./kg bw

Crop

Focal species

Dose

 kg a.s./ha

Short-cut

DDD

TER

Weed control

(early post emergence)

 

 

 

 

 

All proposed uses (also relevant for desiccation uses, but TERs will be lower because of the higher dose rate.)

Screening step:

Small omnivorous bird (100% weeds)

0.4

158.8

63.5

1.81

Potatoes, strawberries

Small omnivorous bird ‘lark’ (50% soil dwelling arthropods, 25% seeds, 25% weeds)

0.4

24.0

9.60

12.0

 

Small insectivorous bird ‘wagtail’ (50% foliar, 50% soil dwelling)

0.4

26.8

10.7

10.7

Beets

Small omnivorous bird ‘lark’ (50% soil dwelling arthropods, 25% seeds, 25% weeds)

0.4

24.0

9.60

12.0

 

Small insectivorous bird ‘wagtail’ (50% ground, 50% soil dwelling)

0.4

10.9

4.36

26.4

Root and Stem vegetables, bulb and onion like crops

Small granivorous bird ‘finch’ (100% seeds)

0.4

24.7

9.88

11.6

 

Small omnivorous bird ‘lark’ (50% soil dwelling arthropods, 25% seeds, 25% weeds)

0.4

24.0

9.60

12.0

 

Small insectivorous bird ‘wagtail’ (50% foliar, 50% soil dwelling)

0.4

26.8

10.7

10.7

Desiccation

(late application)

 

 

 

 

 

Pulses; Legume forage

Small granivorous bird ‘finch’ (100% seeds)

0.6

7.4

4.44

25.9

 

Small omnivorous bird ‘lark’ (50% soil dwelling arthropods, 25% seeds, 25% weeds)

0.6

7.2

4.32

26.6

 

Small insectivorous bird ‘wagtail’ (50% foliar, 50% soil dwelling)

0.6

25.2

15.1

7.60

 

The screening step shows a risk to the small bird feeding only on weeds. Based on the first tier assessment TERs are all above the trigger of ten, except for the small insectivorous bird in the desiccation applications.

It is agreed that an acceptable risk is shown for the granivorous bird feeding on 100% seeds.

However, Ctgb questions whether the assumption of the guidance document that the diet can consist of several food types, as was done for the lark and the wagtail, is sufficiently conservative for the acute time-scale. In an acute feeding bout, a bird may fulfil its complete feed demand with one feed type only. As shown in the screening step, the TER value is below the trigger when the omnivorous indicator species is assumed to feed on 100% non-grass herbs (TER 1.8 for weed control uses and 4.0 for desiccation in pulses and legume forage).  

 

Ctgb will submit this comment on mixed diets in the Guidance document during the evaluation round. In the meantime, it will not be accepted to use a diet consisting of more than one food type for acute risk assessment, unless it has been adequately proven (e.g. with field investigations) that this is in fact relevant for field situations.

 

A refined risk assessment was submitted for the insectivorous bird and is presented below.

 

Refined risk assessment

Residue data on insects is available. The max residue value found was 6.9, corresponding to a max RUD of 12.5 (this value can be used for both foliar and soil dwelling arthropods, see LoE). With this value the short-cut value for the desiccation uses is 9.88 (calculated as FIR/bw 0.79 x RUD 12.5), disregarding interception. With this shortcut value, the TER is (115 / (0.6 x 9.88) =) 19.4 for the desiccation in pulses and legume forage. Note that with this refined RUD data also the single diets for insectivores are covered for the other applications. Thus, the acute risk for insectivorous birds is acceptable. However, there is no refinement available for herbivorous birds and thus, the acute risk to herbivorous birds (or omnivorous birds feeding only on weeds) is not acceptable.

 

Chronic risk assessment according to EFSA (2009)

 

 

Table E.4b chronic risk assessment for birds -  first-tier assessment, using a NOEL of 9.4 mg a.s./kg bw

Crop

Focal species

Dose

 kg a.s./ha

Short-cut

Ftwa

DDD

TER

Weed control

(early post emergence)

 

 

 

 

 

 

Potatoes, strawberries

Small omnivorous bird ‘lark’

0.4

10.9

0.53

2.31

4.07

 

Small insectivorous bird ‘wagtail’

0.4

11.3

0.53

2.40

3.92

Beets

Small omnivorous bird ‘lark’

0.4

10.9

0.53

2.31

4.07

 

Small insectivorous bird ‘wagtail’

0.4

5.9

0.53

1.25

7.52

Root and Stem vegetables, bulb and onion like crops

Small granivorous bird ‘finch’

0.4

11.4

0.53

2.42

3.89

 

Small omnivorous bird ‘lark’

0.4

10.9

0.53

2.31

4.07

 

Small insectivorous bird ‘wagtail’

0.4

11.3

0.53

2.40

3.92

Desiccation

(late application)

 

 

 

 

 

 

Pulses; Legume forage

Small granivorous bird ‘finch’

0.6

7.4

0.53

2.35

3.99

 

Small omnivorous bird ‘lark’

0.6

3.3

0.53

1.05

8.96

 

Small insectivorous bird ‘wagtail’

0.6

9.7

0.53

3.08

3.05

 

Based on the results presented above, a risk is still expected for each proposed application. A further refinement is given below.

 

Refinement granivorous birds

The applicant refines the risk for granivorous birds by including dehusking into the risk assessment:

Granivorous birds are known to de-husk seeds prior to consumption. When this occurs, the actual intake of an active substance resulting from feeding on treated seeds is considerably less than expected. Numerous families of the by far species-richest Order in birds, the Passeriformes (i.e. songbirds) feed infrequently on seeds and/or limited to certain periods in the year, and these species are classified generally as omnivorous (e.g. larks, tits or crows). However, in some other Families of this Order including Passeridae, Fringillidae and Emberizidae seeds are either periodically or even during the whole year a major diet component. Specialisation on seeds as major food items has resulted in a number of different functional and anatomic adaptations in such granivorous species. One such adaptation is an evolved beak structure that allows the bird to crack seeds and discard the husk (de-husking). De-husking is a strongly fixed component of the foraging behaviour of granivorous species (Ziswiler 1965). This behavioural adaptation is so strongly developed that some species e.g. chaffinches (Fringilla coelebs) are unwilling to take seeds that have already been de-husked (Glutz von Blotzheim and Bauer 1997). Finches and ‘finch-like’ granivorous birds, exhibiting a modified beak structure for de-husking seeds, generally de-husk seeds before swallowing the kernel (Ziswiler 1965). No data for de-husking behaviour in the linnet is currently available, but linnets do show as member of the Fringillidae the same beak structure. Prosser and Hart (2005) reported that a close relative of the linnet, the greenfinch (Carduelis chloris; same Genus as linnet, Carduelis cannabina), de-husks 96- 100% of seeds it consumes. Based on these findings, it is assumed that under natural conditions, linnets will de-husk as well 96% of the seeds they consume. A conservative assumption is therefore that linnets will consume up to 20% of their total diet without de-husking the seeds.

 

How much de-husking seeds prior to ingestion reduces the residues to which granivorous birds are exposed to seed treatments was estimated by Edwards et al. (1998), who found that de-husking treated seeds can lead to an average reduction in pesticide intake of 87% (range 80 – 95%). Furthermore, Avery et al. (1997) studied the seed-handling behaviour of granivorous bird species feeding on millet, rice, sunflower and sorghum treated with imidacloprid. House finches (Carpodacus mexicanus), a species of the Fringillidae, i.e. finch family as well, feeding on imidacloprid-treated seeds discarded between 62% and 84% of the chemical that is on the seed. The overall findings led the authors to conclude that the seed-handling behaviour in granivorous birds results in a 60-85% reduction of their exposure to chemicals on treated seeds.

In view of the findings detailed above, a conservative assumption would be that de-husking behaviour in linnets results in a minimum of 60% less uptake of chemical residues from treated seeds. Accordingly, 40% of the residues are assumed to be ingested. Therefore a De-husking factor DH = 0.4 is considered as conservative in the higher tier risk assessment.

 

Reaction Ctgb

Dehusking was taken into account in the new guidance document on birds and mammals. It is considered that dehusking can play an important role in minimizing the risk however:

 

‘…., incorporation of dehusking as a mitigating factor in the DDD equation requires careful consideration of various parameters….

… it is important to note that dehusking is not all-or-nothing: not all small species dehusk, and some species dehusked some but not all of particular seed types. In the wild, the actual amount of seeds dehusked may be dependent on stressors such as feeding pressure, predation or competition (Prosser, 1999).

 

 

It is therefore recommended that:

••If dehusking is to be considered in a higher-tier assessment, case-specific evidence  must be provided that it may actually play a role under field conditions for the relevant focal species;

•• Available information on actual extent of dehusking and on relevant environmental conditions for such behaviour should be thoroughly discussed;

•• Studies with the relevant focal species, the relevant seed type and the relevant product should be considered in preference to other studies requiring extrapolation;

•• Particularly for birds, a risk assessment for a dehusking species should always be accompanied by an assessment for a second species that does not dehusk, in order to conclude on the actual species of concern.

 

In this case, only the linnet was proposed, because it is the proposed focal species from the guidance document, not because field studies showed that this species is really is the most relevant. Although it can be accepted that the linnet (and other finches) dehusk almost all their food, it does not mean that no granivorous species with less or no dehusking behaviour is present in the field. Furthermore, it is unknown how much the exposure is reduced by dehusking. Birds will still come into contact with the a.s. while dehusking, possibly taking up a.s. Certainly, dehusking can be taking into account, but in this case only in a weight of evidence approach and not with a fixed dehusking value for both dehusking and residues ingested. The TER values for the granivorous bird are in the range of 3.9-4.0. Further refinement is necesarry to conclude on acceptable long-term risk for the granivorous bird.

 

Refinement omnivorous birds

In the Canadian field study residues and dissipation on insects and vegetation were measured. The mean RUD of 8.73 mg/kg as well as the DT50 of 1.23 days was accepted before for the refinement of the insectivorous component and the mean RUD of 66.9 mg/kg as well as the DT50 of 1.59 days was accepted before for the refinement of the herbivorous component. For seeds, the mean RUD was 40 or 38 mg a.s./kg (either seeds with or without husk). These values are similar to those reported in the guidance document (40.2). The reported DT50 of 14.2 days was not considered reliable because of the bad fit (r2 = 0.15), however it can be used as a worst-case since higher values than the default are reported. However the default value can be used.  The generic focal species, Fir/bw and diet are the same as the standard first tier assessment. The refined risk assessment is given below

 

Table E.5 Refined long-term risk assessment for the woodlark

Crop

Dose

 kg a.s./ha

Fir/bw

Food type and PD

DF

RUD

Ftwa

DDD

TER

Weed control

(early post emergence)

0.4

0.52

0.25 foliage

 

66.9

0.11

0.383

 

 

 

 

0.25 weed seeds

 

40

0.63

1.310

 

 

 

 

0.50 arthropods

 

8.93

0.085

0.079

 

total

 

 

total

 

 

 

1.772

5.31

 

Based on the risk assessment presented above, an acceptable risk is expected for omnivorous birds.

 

Refinement insectivorous birds

In the Canadian field study residues and dissipation on insects were measured. The mean RUD of 8.73 mg/kg as well as the DT50 of 1.23 days was accepted before for the refinement for wagtails. The refined risk assessment is given below

 

Table E.6 Refined long-term risk assessment for the wagtail

Crop

Dose

 kg a.s./ha

Fir/bw

RUD

Ftwa

DDD

TER

Weed control

(early post emergence)

 

 

 

 

 

 

 

0.4

0.79

8.93

0.085

0.24

39.2

Desiccation

(late application)

 

 

 

 

 

 

Pulses; Legume forage

0.6

0.79

8.93

0.085

0.36

26.1

 

Based on the calculations presented above, an acceptable risk is expected for insectivorous birds.

 

Conclusion

An acceptable risk is expected for the weed control (early pre-emergence) uses in potatoes, beets, leafy vegetables, pulses, fruiting vegetables, cabbages, root vegetables and tubers, stalk vegetables, flower bulbs and bulb flowers.

The risk for bird in early-post emergence  (interrow) uses in agricultural crops (potatoes, beets), strawberries, vegetables (pulses, brassicas root and tuber vegetables, bulbs and onions, stem vegetables), herbs and the desiccation uses in peas, beans and clover is not acceptable.

 

The risk assessment for birds via surface water (drinking water and secondary poisoning via fish) is a Dutch specific aspect, since surface water concentrations are calculated based on national drift values.

 

drinking water

The risk from exposure through drinking surface water is calculated for a small bird with body weight 10 g and a DWI (daily water intake) of 2.7 g/d. Surface water concentrations are calculated using TOXSWA (see paragraph 6.2.1). In the first instance, acute exposure is taken into account. The highest PIECwater is 0.513 mg/L. It follows that the risk of drinking water is (LD50 * bw) / (PIEC*DWI) = (83 * 0.010) / (0.000513 * 0.0027) = >100000.

Since TER ³ 10, the risk is acceptable. 

 

7.1.2    Secondary poisoning