and refined risk assessment placed side by side : pec ... · tier 3d) other modelling approaches...

6th European Modelling Workshop

10-12 October 2012 Paris

Arnaud CONRAD

ANSES

Regulated Product Department (DPR)

Ecotoxicology and E-Fate Unit

France

“keep it short and simple” and Refined Risk Assessment

placed side by side : PEC Groundwater in France

CONTENT

1. Framework of the European risk assessment

2. National groundwater RA in the context of the zonal

assessment

3. Feedback on the refined groundwater RA in FR: Conclusions from FOCUS modelling results compared to

conclusions from FROGS modelling results

4. Conclusions and perspectives

CONTENT


2. National groundwater RA in the context of the zonal assessment

3. Feedback on the refined groundwater RA in FR:

Conclusions from FOCUS modelling results compared to Conclusions from

FROGS modelling results


Current GW risk assessment scheme

Relevant FOCUS (2000) standard

scenarios for the intended uses

All PECgw

< 0.1 µg/L

PECgw < 0.1 µg/L

for at least one scenario

All PECgw

• Parent , relevant metabolites > 0.1 µg/L

• non relevant metabolites > 10 µg/L

MS should deal with the

proposed mitigation

measures

No safe use

=> Decision and risk

management at MS level

Safe use

Current GW risk assessment scheme

Relevant FOCUS (2000) standard

scenarios for the intended uses

All PECgw

< 0.1 µg/L

PECgw < 0.1 µg/L

for at least one scenario

All PECgw

• Parent , relevant metabolites > 0.1 µg/L

• non relevant metabolites > 10 µg/L

No safe use MS should deal with the

proposed mitigation

measures

=> Decision and risk

management at MS level

Safe use

Tier 2b)

Modelling with refined scenarios

= FROGS

Tier 1)

Standard FOCUS scenarios with lab. or field degradation studies

Tier 3a)

Combined

modelling refined

parameters and

scenarios

Tier 2a)

Modelling with refined parameters

Tier 3c)

Higher tier leaching

experiments set into context

by modelling

Tier 3b)

Advanced spatial

modelling

Tier 3d)

Other modelling

approaches

Tier 4)

Groundwater monitoring

* Mitigation possible at all tiers

Tiered assessment scheme for groundwater (FOCUS GW, 2009)

zMS to integrate or not the higher tier (> tier 1)

Not evocated in this presentation

CONTENT


2. National groundwater RA in the context of the zonal

assessment


Conclusions from FOCUS modelling results compared to conclusions from



National RA in the context of the zonal assessment

Tier 1 (Cornerstone of the RA) based on the EU agreed endpoints

All FOCUS scenarios: PECgw < 0.1 µg/L for parent and relevant metabolites

PECgw < 10 µg/L for non-relevant metabolites

Zonal/National registration

including mitigation measures

Refined RA ? zMS to integrate or not higher tier (> tier 1)

Yes

No

Safe use ?

National RA in the context of the zonal assessment

Tier 2a based on the updated EU endpoints when necessary New studies might be used (or not ) to derive new endpoints



Refined RA ? zMS to integrate or not higher tier (> tier 1)

Safe use ? Yes

No



Tier 1 (Cornerstone of the RA) based on the EU agreed endpoints





Yes

No

Safe use ?

Tier 2b/3a Modelling with refined scenarios (EU agreed / updated

endpoints)



For the national registration (addendum):

Implementation of specific scenarios into the national risk assessment in zonal assessment

FROGS MODEL

identification of relevant mitigation measures

National GW risk assessment

… higher tier

Safe use ? Yes

No

Previous talks on specific scenarios (FROGS model)

• FROGS model was presented by Klaus Hammel at the 5th European

Modelling Workshop, 14/15 Oct 2010, Capri, Italy

• Software can be downloaded on

the website and documentation is

available on internet : FROGS

(2011) “French Refinement Of

Groundwater Scenarios” Report of

the UIPP Environmental

Methodology Working Group

version 2.0

http://frogs.eclosion-share.net/documents/FROGSv2222report_07212011.pdf

Tier 2b scenarios describing realistic conditions

• National scenarios only needed if standard European FOCUS scenarios show exceedances

and no relevant mitigation measure can be defined

• Causal analysis of PECgw exceedances enable implementation of mitigation options

Tool developed for 8 major field crops in France (winter wheat, winter barley, oilseed rape,

maize fodder, maize grain, sugar beet, potato and sunflower)

• National approach based on variety of representative conditions rather than worst-

cases

• Realistic environmental conditions in terms of climate, soils and management derived from

readily available data

Analysis of PECgw as a function of

- sand content

- OC content

- available water content of the whole profile

- soil ID

- specific weather and typical rotation of each AU

CONTENT



3. Feedback on the refined groundwater RA in FR: Conclusions from FOCUS modelling results compared to

Conclusions from FROGS modelling results


Feedback on the refined groundwater RA in FR:

• Case 1: FOCUS modelling sufficient to conclude

(majority of situations) _ 1 example

• Case 2: FROGS modelling used to refine the RA

(only 10 dossiers; 2 active substances) _ 1 example

• Case 3: FROGS modelling used to refine the RA, but

conclusion was similar to FOCUS run _ 2 examples

• Case 4: RA based on mitigation measures

unapplicable (Results of the FROGS model not

correctly used to finalise the RA) _ 1 example

• Case 5: the representative crop selected did not

correspond to the intended uses (1 dossier)

For active substance and/or metabolites

Conclusions from FOCUS modelling results compared to conclusions

from FROGS modelling results

Cases

0

20

40

60

80

100

1 2 3 4 5

Nu

mb

er

of

do

ssie

rs (

%)

Total:

500 dossiers

since 2011

Case 1: FOCUS modelling sufficient to finalise the RA

• Majority of cases

• FOCUS modelling performed at a higher rate than the intended uses (risk

envelope)

PECgw > 0.1 µg/L for one location -> RA not acceptable for FR

FROGS modelling available to refine the RA -> RA acceptable

ANSES position :

Approach not accepted; FROGS modelling not assessed

FOCUS-PECgw < 0.1 µg/L for all locations when the intended applied rate was

considered

FROGS modelling only considered to refine the RA.

=> Use to avoid mitigation measures (suggested from FOCUS

modelling) considered as not justified :

- Adequated rate

- Application dates

- Number of applications

- Application every other year, every third year

Principes généraux de l’évaluation du risque pour les eaux souterraines

DT50 (days) 20

Koc (cm3/g) Variable; related to the soil clay content

1/n (-) 0.9

Crop uptake factor (-) 0.5

Application rate (g/ha) X on Maize

Application date/stage BBCH 10-18

• FOCUS-PECgw: calculated at 1m depth

monoculture (Maize)

• FROGS-PECgw: calculated at the bottom of the soil profile (40 to 140 cm)

Maize (primary crop, rotational crop, monoculture considered (conservative

approach)

EU agreed endpoints

Case 2: FROGS modelling used to refine the RA

Active substance (AS) 1 on Maize

Case 2: AS 1 on Maize

Uses FOCUS Scenarios

Maize; every year

PECgw > 0.1 µg/L for one scenario

Maize; every other year

PECgw < 0.1 µg/L for all scenarios

Tier 1: 80th centile average PECgw (µg/L) at 1 m depth for AS 1

National restriction based on FOCUS modelling :

« SPe 2: Do not apply on maize a product containing SA1 on soil

having less than 10% of clay, and not more than every other year »



Tier 2b:

FROGS 80th/90th centile PECgw and FOCUS 80th percentile PECgw

0,0

0,2

0,4

0,6

0,8

1,0

0,000 0,005 0,010 0,015 0,020

Cu

mu

lative

are

al d

istr

ibu

tio

n (

-)

80th centile PECgw (µg/L)

Chateaudun

Kremsmuster

Sevilla

Thiva

Okehampton

Porto

FROGS 90th PECgw:

0.002 µg/L

Hamburg

FOCUS PECgw: 0.16 µg/L

Piacenza


Tier 2b : Distribution of FROGS-PECgw (temporal 80th centile) for SA1 related to clay

content of soil (%)

National restriction based on FROGS modelling :

None



AS 2 on Sugar beets Case 3a:

Mitigation measures FOCUS Scenarios

Application every year PECgw > 0.1 µg/L for at least one scenario

Application every other year PECgw > 0.1 µg/L for at least one scenario

Application every third year PECgw < 0.1 µg/L for all scenarios

Tier 1: 80th percentile average PECgw (µg/L) at 1 m depth for SA2

National restriction based on FOCUS modelling :

SPe1: To protect groundwater, do not apply this or any other product

containing SA2 more than once every third year.

in agreement with the agricultural practices

• EU agreed endpoints

• FOCUS-PECgw: monoculture (sugar beets)

• FROGS-PECgw: sugar beets (primary crop, rotational crop)


Substance

PECgw,

min

(µg/L)

PECgw,

max

(µg/L)

% of area

with PECgw

> 0.1 µg/L

AS 2 < 0.001 0.886 6.3%

National restriction based on FROGS modelling :

Application on primary crop only

- Acceptable for application rotational crop every third year on primary

crop

- Similar conclusion compared to results obtained from FOCUS model


Case 3a: AS 2 on Sugar beets

Tier 2b: National approach based on variety of representative conditions

90th percentile PECgw = 0.085 µg/L

Metabolites X

80th centile >> 10 µg/L

Metabolites X

90th centile >> 10 µg/L

X1 :

(max. 11.7 µg/L ; 2 scenarios/6)

X2 :

(max. 16.4 µg/L ; 1 scenario/6)

X3 :

(max. 13.2 µg/L, 1 scenario/6)

X4,

X5 <10µg/L

X6

X1:

(13.6 µg/L)

X2:

(11.3 µg/L).

X3,

X4,

X5 <10µg/L

X6

FOCUS modelling

(PEARL v4 + PELMO v4)

FROGS modelling

(FROGS v2)

National restriction based on both FOCUS and FROGS modellings :

=> no safe use

Uses : Oil seed rape; 1000 g/ha; Treatment every third year

Case 3b:

Unapplicable mitigation measures

• Proposed mitigation measure based on the FROGS modellings can be

scientifically acceptable, BUT not applicable for the risk manager

e.g., 90th centile PECgw < 0.1 µg/L if soil clay content < 10%, and

available water capacity ranged from X and X %

• Fortunately, not observed since the guidance document FROGS (2011) exists

Case 4:

CONTENT




Conclusions from FOCUS modelling results compared to conclusions from



Conclusions

Specific scenarios improve the realism of EU modellings, however results

from specific scenarios do not lead to very different conclusions than those

obtained using the FOCUS tool.

Modellings using FROGS model: few cases proposed in the framework of

the zRR

Specific scenarios permit to conclude without mitigation measures, but not

all the time (no magic answer)

In the context of the zonal assessment, mitigation measures should be

preferably proposed in the core assessment based on EU models (time

optimisation ….)

-> Risk assessment kept simple

Limits, Perspectives

Crop not supported in FROGS model: surrogate not acceptable

Evolution/adaptation of scenario implemented into the model (i.e.,

rotational crop …)

e.g., rotational crops as oil seed rape

Thank you for your attention …

and refined risk assessment placed side by side : pec ... · tier 3d) other modelling approaches...

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