1. Committed since 2002
to ensuring that Europe’s food is safe
Draft Guidance Document on Pesticide Exposure Assessment
for Workers, Operators, Bystanders and Residents
ECPA – IBMA- EFSA Workshop
1
Parma, 26th April 2012

2. Background
• In 2006 EFSA ran an
investigation among MSs to
ask the priorities of Guidance
Documents
• One of the claims was the
development of a new GD on
operator exposure assessment
• Prioritised by EFSA
2

3. Background
• 2007: Call to outsource the information gathering and
evaluation of the existing models/activities (Art. 36. of
Regulation 178/2002)
• 2008: Report from outsourced work carried out jointly by the
UK Pesticides Safety Directorate (PSD) and the University of
Ghent (UG).
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4. Scientific Opinion
• 2009: Public consultation on the draft scientific opinion on
Preparation of a Guidance Document on Pesticide Exposure
Assessment for Workers, Operators, Bystanders and Residents,
containing the draft GD (as an annex).
• In response to the comments received, various clarifications
and amendments were made.
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5. Public Consultation
Table 2: Comments received on the draft opinion and GD per organizations and countries
Organization Country Number
ECPA BEL 20
IPH BEL 8
Health Canada - Pest Management Regulatory Agency CAN 14
National Institute of Public Health CZE 1
Federal Environmental Agency DEU 1
Federal Institute of Risk Assessment Berlin DEU 17
Danish EPA DNK 1
INSHT/MTIN ESP 2
Finnish Institute of Occupational Health FIN 14
AFSSA (Agence Française de Sécurité Sanitaire des
FRA 22
Aliments)
BCPC GBR 1
Nufarm UK Ltd GBR 11
Health and Safety Executive GBR 1
Silsoe Spray Application Unit, The Arable Group GBR 10
JSC International Limited GBR 6
Toxicology Unit, PCS, Department of Agriculture,
IRL 9
Fisheries & Food
The Netherlands NLD 37
Swedish Chemicals Agency (KemI) SWE 9
US Environmental Protection Agency, Office of
USA 2
Pesticide Programs
Total number of comments 186
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6. Scientific Opinion
• 2010: Scientific Opinion on Preparation of a Guidance
Document on Pesticide Exposure Assessment for Workers,
Operators, Bystanders and Residents, containing the draft GD
(as an annex), adopted by the PPR Panel on 27 January 2010.
Available online:
www.efsa.europa.eu/en/efsajournal/pub/1501.htm
• 2010: Outcome of the Public Consultation on the Draft
Scientific Opinion on Preparation of a Guidance Document on
Pesticide Exposure Assessment for Workers, Operators,
Bystanders and Residents
Available online:
www.efsa.europa.eu/en/efsajournal/pub/1517.htm
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7. Introduction
• The starting point for this opinion was an outsourced project
carried out jointly by the UK Pesticides Safety Directorate
(PSD) and the University of Ghent (UG).
• Relevant new data could be expected from several sources
over the next five years. The PPR Panel concluded that it
would be worth developing the Guidance Document for
immediate use.
• This could then be revised, as and when new data emerged.
• During drafting, the Panel aimed for a level of precaution
similar to, or somewhat higher than, that which is currently
applied, but changing the level of precaution if necessary, can
be performed without major restructuring of the text.
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8. Main contents
• The opinion starts by defining the scope of the Guidance
Document (Section 2).
• It then reviews the legal requirements that underpin the
relevant components of risk assessment for plant protection
products (Section 3).
• It describes the methods of risk assessment that are currently
used (Section 4), and considers their adequacy and limitations
(Sections 5 and 6).
• Next it proposes a revised approach to exposure and risk
assessment for operators, workers, residents and bystanders,
and gives the underlying rationale (Section 7).
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9. Main contents
• Section 8 then builds on the PSD/UG review, setting out
proposals for standard models and data sets that should be
used as a default when estimating exposures for different
scenarios, and giving reasons for choices where more than one
option is available.
• Section 9 provides a link to the draft Guidance Document,
which is set out in Appendix 1. Finally, there is a brief
summary of conclusions and recommendations.
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10. Scope
• The Guidance Document is intended for use in relation to
chemical PPPs
• It does not apply to biocides, which are the subject of separate
legislation (Directive 98/8/EC), or to biological pesticides.
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11. Scope
• Definitions of exposed groups
 Compatible with the draft Guidance Document on AOELs
that is currently in use.
• The main focus of the opinion is risk assessment for systemic
toxicity
 it does not cover all the aspects of exposure that could be
relevant to localised toxicity such as respiratory irritation,
and
 it does not provide guidance on the quantification of dermal
absorption.
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12. New approaches
Proposed percentiles
• A particular challenge in exposure estimation is the wide
variability (often over several orders of magnitude), between
individual measurements of exposure associated with the same
exposure scenario.
• One implication of the substantial variability of pesticide
exposures for a given scenario is that the 50th or 75th centile
from a set of measured exposures might importantly
underestimate some individual exposures on a single day.
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13. New approaches
Acute risk assessment
• In the current practice operator and other non-dietary pesticide
exposure assessments consider repeated exposure
 often geometric/arithmetic mean, 75th centile, 90/95th
centile exposure values
 occasional higher exposures not assessed
• The underestimation of exposure could be more important
where toxic effects could result from acute exposure on a
single day.
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14. New approaches
Acute risk assessment
• For PPPs which might cause toxicity through exposures on a
single day, a separate acute risk assessment should be carried
out
• The acute risk assessment for operators, workers and
bystanders will require the specification of a separate
toxicological reference value, an “acute AOEL∗” (“AAOEL”),
derived from a relevant study or studies.
• This should not require any additional use of experimental
animals.
• The AAOEL should be used as a reference for realistic upper
estimates of exposure in a single day for operators, workers
and bystanders.
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15. New approaches
Statistical variability
• Estimates of exposure derived from empirical data sets are
subject to statistical uncertainty.
• This could lead to substantial underestimation of potential
exposures
• To address this problem, in addition to the relevant centile of
the empirical data set, a parametric estimate should be made of
the corresponding centile in the theoretical population from
which this sample of measurements was derived with the
assumption that the population has a log-normal distribution.


( )
exp  x + t n −1,a * S * 1 + 1 
n

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16. New approaches
Proposed percentiles
• For risk assessments in relation to acute exposures (i.e. those
that could occur in a single day), exposure estimates should as
a default be derived as the higher of:
a) the 95th centile of the distribution of measurements in the
sample; and
b) a statistical estimate of the 95th centile for the theoretical
population of measurements from which the sample was
derived, under the assumption that this population has a
log-normal distribution.
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17. New approaches
Proposed percentiles
• For risk assessments in relation to longer term exposures,
exposures should as a default be derived as the higher of:
a) the 75th centile of the distribution of measurements in the
sample; and
b) a statistical estimate of the 75th centile for the theoretical
population of measurements from which the sample was
derived, under the assumption that this population has a
log-normal distribution.
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18. Harmonisation
Proposed methods and standard data sets
OPERATOR EXPOSURE
• In current practice multiple models are used
 Pooling data?
 Data quality issues (EUROPOEM)
 Professional judgement to select most “robust” individual
data sets
• Typical (main) scenarios identified
• Scenario exposure data sets taken from EUROPOEM, German
model, PHED and interpreted according to GD
• Several scenarios without data, and protective surrogates
proposed
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19. Harmonisation
Proposed methods and standard data sets
Choices of standard models and underpinning data sets for first tier estimation of exposures in
operators when mixing and loading
Scenario Formulation Sources of data
Dermal exposure Inhalation exposure
SOLIDS
1 a (i) Large scale (e.g. tractor- WP, SP German model (PDE) PHED
mounted) equipment
[German model has most robust dataset] [PHED has larger and more robust data
set than EUROPOEM and German
model]
(ii) GR, FG PHED (ADE) PHED
[PHED has larger and more robust data set than [PHED has larger and more robust data
EUROPOEM] set than EUROPOEM]
[Data for exposure to body not log-normal, use [Data not log-normal, use parametric
parametric estimate for 95th centile] estimate for 95th centile]
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20. Harmonisation
Proposed methods and standard data sets
Specific exposures during mixing/loading (potential exposures except where indicated otherwise)
Scenario Formulation Standard 75th and 95th Specific Exposure Centiles
(mg exposure/kg a.s. mixed/loaded, excepted where stated otherwise)
Dermal exposure Inhalation exposure
SOLIDS 75th Centile 95th Centile 75th 95th Centile
Centile
1 a (i) Large scale (e.g. Tractor WP, SP Hands 13.5 Hands 48.0 0.248 0.973
mounted) equipment
(ii) GR, FG Hands under Hands under 0.0146 0.0784
protective gloves protective glove
0.00145 0.00688
Body under coverall Body under coverall
0.00198 0.036
(iii) WG, SG Hands 3.52 Hands 9.20 0.0332 0.140
1 b (i) Medium scale (e.g. WP, SP Hands under Hands under 1.53 4.06
Professional hand-held) protective gloves 10.7 protective gloves 39.4
equipment mg in-use mg in-use
preparation/min preparation/min
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21. Harmonisation
Proposed methods and standard data sets
WORKER EXPOSURE
• EUROPOEM DFR & TC approach
Potential dermal exposure (PDE) µg/day = DFR µg/cm2 x TC cm2/h x T h/day
 DFR dissipation no data default t/2 = 30 days
 TC values
i) Total potential exposures
ii) Arms, body and legs covered
• Inhalation exposure in greenhouses
Potential inhalation exposure (mg a.s./hr inhaled) = Application rate (kg/a.s./ha) x
Task Specific Factor (ha/hr x 10-3)
• Residues in soil/compost
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22. Harmonisation
Proposed methods and standard data sets
RESIDENTS (i)
• Spray drift
 Arable crop single pass 8m distant, dermal data 10x
adjustment
 Commission: level of precaution?
 Orchard crop whole orchard 8m distant, no adjustment
• Vapour drift using the method that has been developed in the
UK (CRD, 2008) and Germany (Martin et al., 2008)
 24 h TWA
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23. Harmonisation
Proposed methods and standard data sets
RESIDENTS (ii)
• Exposure to surface deposits (fallout in garden)
 sum of dermal transfer, plus young children hand- and
object- to mouth
• Entry into treated crops
 only dermal exposure, DFR as for workers, 15 minutes
exposure/day
 on treated lawn drift percentage 100%
• Residues in crops grown adjacent to treated areas - future?
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24. Harmonisation
Proposed methods and standard data sets
BYSTANDERS
• Same 4 pathways as residents
 Spray drift pathway
95th centile exposure spray values
 Surface residues
Higher TCs
Higher hand-to-mouth frequency (20 events /hour)
 Vapour drift and entry into treated crops same values as
residents
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25. Harmonisation
Proposed methods and standard data sets
• The Panel has also made proposals for default assumptions
 Body weights
 Adults & children
 Breathing rates
 Latest EPA approach
 Scale of use (work rates)
 Reflecting equipment used in data
 PPE and level of protection
 TNO Review, similar to biocides
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26. Draft Guidance Document
• Designed to assist risk assessors and notifiers when
quantifying potential non-dietary, systemic exposures as part
of regulatory risk assessment for plant protection products
(PPPs).
• Risk assessments must be carried out for all scenarios of
exposure to operators, workers, residents and bystanders that
can be expected to occur as a consequence of the proposed
uses of a PPP.
• Most exposure scenarios will fall into a category for which a
standardised first tier exposure assessment can be applied as
described in this document.
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27. Draft Guidance Document
Overall approach
Step one: Identification of risk assessments that are required
Risk assessments that may be required(a)
PPPs with no significant potential PPPs with significant potential for
Exposure group for toxicity from exposure in a toxicity from exposure in a single
single day day
Operators L AL
Workers L AL
Residents L L
Bystanders A
(a): A = acute, L = longer term
International Fresenius Conference for the Agrochemical Industry
Operator and Resident Exposure and Risk Assessment 27
Mainz, 13-14 December 2010

28. Draft Guidance Document
Overall approach
• Step two: Use standardised first tier methods of exposure
assessment where available.
Where available, a single, relevant, standard dataset of
adequate quality was identified and proposed by the PPR
Panel for each exposure scenario. This should then be used to
derive the exposure values that will be applied in the risk
assessment.
• Step three: Use appropriate ad hoc methods where
standardised first tier methods of exposure assessment are not
available.
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29. Recommendations
• The PPR Panel recommends that a new guidance document
on exposure assessment for operators, workers, residents and
bystanders should be adopted along the lines of that set out in
Appendix A.
• Risk managers in the European Commission wish to vary the
level of precaution that is applied, the guidance should be
modified accordingly.
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30. Recommendations
• Once the exact format of the guidance document has been
agreed by risk managers, it should be published with a
supporting spreadsheet to enable easy application by notifiers
and regulatory authorities, and also a separate document
detailing the derivation of specified exposure values from
underlying datasets.
• The Guidance Document should thereafter be reviewed
periodically, as and when relevant new data become available,
and if appropriate, be revised.
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31. Current Mandate of EFSA
• Consultation of risk managers in the European
Commission took place in May 2011- Risk management
options (e.g. percentiles, default values) included in the draft
guidance document were discussed and agreed.
• The outcome of these discussions was communicated to
the Standing Committee on the Food Chain and Animal
Health and to EFSA in 2011.
• As a consequence EFSA received an external mandate
from the Commission, with the preparation of the EFSA
Guidance Document on Pesticide Exposure Assessment
for Workers, Operators, Bystanders and Residents.
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32. Current Mandate of EFSA
• Preparation of an EXCEL calculator sheet facilitating the
use of the methodologies presented in the EFSA Guidance
• An EFSA working group is being established to prepare
this Guidance Document under the lead of the Pesticide
unit.
• Circulating the draft EXCEL calculator to the
Commission and stakeholders for a trial phase foreseen at
the end of July 2012.
• Expected deadline for finalization of the EFSA Guidance:
End of 2012.
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