aggregate and cumulative risk of pesticides: an on-line integrated strategy

ACROPOLIS: March 30- April 1, 2011

Aggregate and Cumulative Risk Of Pesticides: an On-Line Integrated Strategy

WP3: Aggregate exposure assessment

Task 3.3

• Testing the aggregate model with specific scenarios

• FERA - Typical populations and situations of dermal exposure as a consequence of the use of pesticides in the United Kingdom.

• UMIL - Worker/operator exposure in the Italian situation.

• RIVM will describe typical populations and situations for consumer products exposure including inhalation exposure

ACROPOLIS: March 30 - April 1, 2011

Task 3.3

• Case studies for the UK

• Consider two groups; conazoles and synthetic pyrethroids

• In the first stage conazoles will be considered

• Main use of conazoles is with cereals

• UK POEM and EUROPOEM have data for dermal and inhalation exposure

• Data are for individual studies

• Better to access underlying data for individual exposures


Case studies UK

• UK pesticide usage data• Area of UK treated

• Dose rates, application rates

• Frequency of treatments on individual fields

• General information about method of application

• Recent data allows further information on working practices

– hours/day

• 2011 data (EFSA projects) will allow further information to be used

– Type of sprayer

– Use of PPE

– etc.


Case studies UK

• UK pesticide usage data• Consider the Bystander & Resident exposure to conazoles

• Usage patterns and timings

• Frequency of treatments on individual fields

• Consider using input parameters from usage data

– Application method etc

• Data from BREAM model


Case studies UK

• Other sources of exposure to conazoles to be considered in the validation

• Home and garden

• Pharmaceuticals, etc.

• Dietary intake


Examples of data Greece


Operators: EUROPOEM (UK POEM, German Model, Dutch Model)

Note, that different models may address different activities.

RE-ENTRY (WORKER)DFR x Tc x T=ExposureNote, that Tc is derived by dividing DFRxTby measured exposure. DFR probably a distribution, (95% chosen by regulators?)

VET MEDICINESOnly data source: sales data

ACTIVITIES:a) Tractor boomb) Broadcast air

assistc) Hand heldd) etc.

a) GH ornamentalb) GH vegc) Field Vegd) etc..

a).....b).....

a) 1.5%b) 0.7%c) 1.2%d) Etc.

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HOME & GARDEN (Amateur)Model from BROWSE

CONSUMER PRODUCTSCONSEXPO model (RIVM)

BYSTANDER & RESIDENT (referring to main crops)BREAM model

OTHER?

BIOCIDESOnly data source: sales data

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EXPOSURE RANGE FOR CERTAIN SCENARIOS

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EXPOSED POPULATION

2DMC SIMULATION MATRIX

SOURCE OF EXPOSURE

Case studies Italy

• Consider use of conazoles in vines (links to BM study)– Other possible uses in horticulture with hand held

application techniques

• Data on usage related to industry sales data– Consider use of residue monitoring data to estimate usage

• Use of EUROPOEM model or other data available in public domain e.g. SMT project 1996-2000

• ECPA Greenhouse model data?• EFSA project will provide data in 2011


Case studies Italy

• Biomarker and duplicate diet study• UMIL, with support from FERA will perform a biomarker study

suitable for validation of the intake.

• Exposure of 40 operators and workers involved in conazoles

• Other sources of pesticide exposure such as dietary and from non-professional use of consumer products for the workers will be assessed by UMIL and INRAN using a food record method recording the food intake of the respondents as accurate as possible.

• The food record method will be prepared by INRAN before the start of the biomarker study.

• INRAN, in cooperation with UMIL, will collect duplicate portions

of food eaten by the respondents.


Exposure – broad scenarios

PPPs | Operator exposure: Mixing and loading, Applicator, Equipment cleaning

Biocides |

Vet Meds | Worker exposure: Re-entry tasks

Amateur Operator exposure Mixing and loading, Applicator, Equipment cleaning

(Home & Garden)

Consumer / User exposure Topical use, Ingestion

Pharma

products

Bystander Short term exposure Activities usually away from the home

Resident Long term Activities usually in the home or garden


PPP exposure

• EUROPOEM (UK POEM, German, NL)– Applicator– Re-entry– BystanderNew data sources

Development of BREAM

• Limited information in some cases– Not all use scenarios covered– Work rates and usage data– Contact and transfer rates– Dermal absorption rates– Use/protection factor of PPE



Individual person exposure

Single study data for exposure

Data for scenario exposure.Means, 75th,95th centiles

What data exists for operator exposure


Potential dermal exposure

Dermal exposure

Use of data in models

Systemic exposure

PPE type (if any)PPE penetrationAmbient conditions, etc.

Product typeConcentration/distributionAmbient and skin conditions

Airborne conc.

Actual inhalation exposure

Sampling efficiencyBreathing rate

100% absorption

Use of study data

• Limited use scenarios– Often relates to major uses– Few data sets from “minor” uses or small scale

farming

• Representative data?– Use types– Operator experience/competence– Use of new PPE

• (not necessarily CE marked chemical protective clothing

• Study data vs surveillance data


BEAT

The Bayesian exposure assessment tool is a model that integrates expert judgment and objective measurements

Bayesian framework, a rule base (expert judgment).

Database with dermal exposure measurements (biocidal products)

contextual information.

• Algorithm describing the similarity between exposure scenarios

present in the database and the process described by the assessor

• Provides an exposure estimate for the process• Estimate of the uncertainty• Worked examples for all 23 biocide product types.


BEAT

• An export facility to an Excel exposure calculator that presents a calculation of internal dose in an approved standard format for each worked example.

• A database of measured exposure data (inhalation and dermal) for a wide range of occupational exposure scenarios relevant to biocides. Data are presented generically in terms of in-use formulation as rates of dermal exposure per minute and as air concentrations (low volatility formulations only). This database contains full contextual information on every measurement.

• Task-based search algorithms that search the measurement database on the basis of information provided in a worked example (e.g. formulation properties, tasks performed, method of application, environment and control measures) and return the most appropriate generic data sets. The search algorithm ranks these data sets according to their strength of analogy with the user provided information. It should be cautioned that these algorithms have only been designed to assess analogy between dermal exposure scenarios.

• Automated statistical analysis providing summary statistics and recommended indicative exposure values for each dataset.


ConsExpo

• Exposure to a constant aerial concentration in a single room• Exposure to a chemical emitted from a source into indoor air in

a room ventilated by ambient air• Exposure to a chemical evaporating from a pure substance into

a room ventilated with ambient air• Exposure to a chemical evaporating from a product containing a

mixture of chemicals into a room ventilated with ambient air• Exposure to carbon monoxide in a room where a natural gas

combustor emits exhaust gas• Exposure to a chemical evaporating from paint applied to a

surface layer in a single room• Indoor exposure to a chemical in spray droplets, where the

droplets are well mixed in the room and no evaporation of the chemical occurs


• CalendexTM – Complex model for performing aggregate and cumulative assessments of population exposures to pesticides. The fact that the model contains hard-wired US data sets and its focus on pesticides limits its utility for comprehensive exposure assessment.

• CalTOX – Model of intermediate complexity, which simulates both chemical fate in the environment and subsequent human exposure via a comprehensive range of pathways. Designed for local hazardous waste site exposures but may be more generally applicable.

• CARES – Population-based model for performing aggregate and cumulative assessments of pesticide exposures. Focuses on a limited range of exposure situations and uses US datasets but model is freely available and has the potential to be adapted for additional scenarios.

• CLEA – UK developed model for assessing exposures levels resulting from direct and indirect contact with contaminated soil and for defining soil guideline values. Limited consideration of exposure situations and pathways and conservative nature restrict its utility as a comprehensive exposure assessment tool.

• Consumer - Simple model for assessing dietary pesticide exposures using UK consumption data. Only considers a single exposure pathway and adopts a conservative approach.

• EASE – Semi-quantitative model for assessing occupational exposures. Incorporation of measured workplace exposure data in the model limits its utility for non-occupational situations.


• EUSES – Comprehensive model system, which assesses chemical fate and human exposure via the environment, diet, consumer products and the workplace. Designed for a specific legislative purpose and lacks flexibility.

• Intake Programme – Simple dietary exposure assessment tool. Lacks sophistication of US dietary models in terms of how uncertainty and variability are incorporated into model calculations. Only considers a single exposure pathway.

• LifeLineTM – Complex model for simulating aggregate and cumulative pesticide exposure levels for US populations. Incorporates variability and uncertainty in a sophisticated manner. Applicability of model for non-pesticides is currently limited.

• REx – Flexible system for assessing residential exposure levels. Scenarios are designed for pesticide products thus restricting the general remit of the model.

• RISC – Mechanistic model of chemical fate and subsequent human exposures relating to contaminated land, air and water. Both screening level and higher tier assessments can be performed using the model. Applicable for a limited range of exposure situations.

• SHEDS – Series of models in development for assessing US population exposures to a variety of contaminants (current versions for pesticides and particulate matter). Incorporates detailed activity data currently unavailable for the UK.


aggregate and cumulative risk of pesticides: an on-line integrated strategy

Documents

data available

underlying data

inhalation exposure

measured exposure

biocidesonly data source

ecpa greenhouse model

situations of dermal

case studies italybiomarker