Risk Assessment

Risk Assessment of Pesticide Residues based on SPRT data

Sri Noegrohati

Fac of Pharmacy

Gadjah Mada University

Estimation of Pesticide MRLs

Hazard

Select the most appropriate toxicological endpoint in the most relevant species.

Select a toxicology study appropriate for duration of the exposure.

Apply safety/uncertainty factors to establish reference doses for use in risk assessments.

RISK = f(HAZARD, EXPOSURE)

EXPOSURE = f(CONSUMPTION, RESIDUE)

HAZARD CHARACTERIZATION

High daily consumption for acute assessments

Average daily consumption for chronic assessments

Dose-response extrapolation

Dose response relationship

Repeated Toxicity testing

induce delayed effect due to accumulation of the chemical in the body

Or other mechanism

OECD guideline 407 (14 to 28 days)

OECD guideline 408 (90 days) for subchronic studies

No Observed Effect Level (NOAEL)

Environmental Safety evaluation

Exposure: model of ecosystem to simulate real ecosystem, closed or open system to the air, rainfall may be simulated

Multi species tests organisms, i.e. for terrestrial ecosystem: representatif bacteria, plants and invertebrates, at least 5 species of different taxa

Toxicological end point: NOAEL or NOEC

CONSUMPTION

Probabilistic Dietary Risk Assessment

Exposure = f(consumption distribution, residue distribution)

99.9th percentile

Number of People

Exposure (mg/kg bw/d)

Compare to tox endpoint

Distribution of exposure

Distribution of residues

Distribution of residues

Number of samples

Number of samples

x variability and processing factors

Number of People

Amount Food Consumed (kg/person/day)

Number of People

Amount Food Consumed (kg/person/day)

Distribution of consumption

Distribution of consumption

Distribution of consumption data - UK dietary surveys (1986-87; 1992-93); (adults, 16-64 years; toddlers, 1.5-4.5 years)

Distribution of field residue data from supervised trials

Risk Assessment of long-term (chronic) exposures to pesticide residues in food

Acceptable Daily Intake (ADI)

estimate of the amount of a substance in food and/or drinking-water, normally expressed on a body weight basis, that can be ingested daily over a long-term (month, year, lifetime), without appreciable health risk to the consumer on the basis of all the known facts at the time of the evaluation.

ADI are expressed in mg substance/kg body weight/day.

Risk Assessment of long-term (Cont)

For chronic dietary intake the median represents the long term typical residue if a consumers diet is consistently derived from crops treated at maximum GAP (highest registered application rate, minimum pre-harvest interval, etc).

The STMR is a good starting point for chronic intake estimation (SPRT).

Calculation of Chronic Intake

TMDI = (MRLi Fi)

IEDI = (STMR-Pi Fi)

Where:

Risk Assessment of short-term (acute) exposures to pesticide residues in food

The acute RfD of a chemical is an estimate of the amount of a substance in food and/or drinking-water, normally expressed on a body weight basis, that can be ingested over in a period of 24 hours or less, without appreciable health risk to the consumer on the basis of all the known facts at the time of the evaluation (JMPR 2002)

Supervised residue trials: HR

Calculation of Acute Intake

Composite sample reflects residue level in a daily Large Portion (LP) of the food.

Large portion size - 97.5th percentile of eaters of that food.

Children and total population

Risk Evaluation

Example: SPRT of Deltamethrin in Indonesia

National Estimated Daily intake, NEDI, 18.9 g/person or 3% ADI,

International Estimated Daily intake, IEDI, highest calculated was 147.1 g/ person or 20% ADI.

National Estimated Short Term Intake, NESTI average adult 0.004 g/kg b.w. or.008% ArfD,

International Estimated Short Term Intake, IESTI, calculated based on US uptake 0.038 g/kg bb. or.026% ArfD.

STMR obtained from SPRT of Deltamethrin in Indonesia could be used as proposed MRLs

Recommendation for Deltamethrin MRL

95th percentile 0.0179 mg/kg

99.5th percentile 0.0358 mg/kg

The recommended MRL for Deltamethrin in fresh hot chilli pepper : 0.03 mg/kg

Preparing a Data Submission

Directory

1. Background information

2. Metabolism and environmental fate

3. Methods of residue analysis and data on freezer storage stability

4. Use pattern

5. Residues resulting from supervised trials

6. Fate of residues in storage and processing

7. Residues in animal commodities

8. Residues in food in commerce or at consumption

9. National maximum residue limits and residue definitions

Background information:

explain the reasons for the data submission and briefly list the information included in the report

[LOGO]

TITLE: [COMPOUND].[NATIONAL GOVERNMENT]SUBMISSION FOR JMPR 2005.

PURPOSE:

To provide information on [compound] to the FAO Secretary of JMPR for evaluation by JMPR at the 2005 meeting. [Compound] is on the FAO Panel schedule as a [periodic review] compound for evaluation in 2005.

REPORT NUMBER: [unique identifying number]

NUMBER OF PAGES: [n] pages + annex + attachments

DATE OF ISSUE: [xxxxx].

AUTHORS: [Names of responsible authors and contact persons]

ADDRESS:

[Full address]

AUTHORISATION: [Head of national delegation to CCPR or other relevant position]

ADDRESS:

[Full address of authorising officer]

Analytical methods

Use pattern

Summarise use patterns as provided on labels.

Ensure that the use pattern in the trials matches a label use pattern

Residue trials - supporting information 1

Crop:

Study report identification number:

Analytical method ident number:

Procedural recoveries:

Trial design:

Plot size:

Sprayer:

Sprayer calibration:

Residue trials - supporting information 2

Field sample size:

Sampling dates:

Analysis dates:

Interval of sample storage:

Sample storage conditions:

Residue levels in samples from control plots:

Residues adjusted for % recovery?

Summary of residue trials

Residues in food in commerce or at consumption

Summarise residue monitoring data in standard tables.

In the residue monitoring data from the [national government] residue survey, results of 2003-2004, [list of commodities] were analysed for [compound] residues.

Product

Consumption

g/person/day

Rice279.30

Wheat114.80

Potatoes19.20

Soya sauce11.00

Sugar refined43.00

TOTAL OF VEGETABLE

OILS AND FATS14.20

Brassica vegetables11.20

Cabbages9.70

Fruiting veg. Cucurbits18.20

Fruiting veg. Non-

cucurbits12.50

Far Eastern

IESTI =

LP

*

HR

bw

[

LOGO

]

TITLE:

[

COMPOUND

].

[

NATIONAL GOVERNMENT

]

SUBMISSION FOR JMPR 2005.

PURPOSE:

To provide information on

[

compound

] to the FAO Secretary of

JMPR for evaluation by JMPR at the 2005 meeting.

[

Compound

] is on the FAO Panel schedule as a

[periodic

r

eview

] compound for evaluation in 2005.

REPORT NUMBER:

[

unique identifying number

]

NUMBER OF PAGES:

[n]

pages + annex + attachments

DATE OF ISSUE:

[

xxxxx

].

AUTHORS:

[

Names of responsible authors and contact

persons

]

ADDRESS:

[

Full address

]

AUTHORISATION:

[

Head of national delegation to CCPR or other

relevant position

]

ADDRESS:

Summary information for each method is provided.

Method identification number and reference:

Substrates:

[e.g. plant material, vegetable oils, wine]

Analytes:

[parent compound, metabolite 1, etc]

LOQ:

[0.05 mg/kg]

Recoveries

: [e.g. 78-110% for plant material spiked at 0.05 to 2 mg/kg, n=12]

Method description:

[Very brief summary, for example: Homogenized sampl

es were

extracted with aqueous methanol. The extract was cleaned-up on a cation

exchange cartridge. HPLC (single-column or two-column-switching systems) with

UV detection (

max

270 nm) was used for the final measurement.]

Table

1

. Registered uses of

[compound]

in

[country]

.

Crop

Formulation

Method

Timing

Rate kg

ai/ha

Spray conc

ka

ai/hl

No

PHI,

days

Apples

WP 900

foliar

from bud

opening

0.90

0.090

3

28

Cherries

SC 400

foliar

from petal

fall

0.040

4

28

Table

1

. [

Parent compound

] and [

metabolite M

] residues in [

commodity]

resulting from

supervised trials in [

country

].

CROP

Application

PHI

Residues

Ref

country, year

(variety)

Form

kg ai/ha

kg ai/hl

water,

l/ha

no.

days

Commodity

[parent]

mg/kg

[metab]

mg/kg

Establish the pesticide use pattern

necessary for pest control

Pesticide toxicology studies

Estimate values for

ADI and acute RfD

RISK ASSESSMENT

Are the toxicology and dietary

intake of residues compatible?

Set official MRL

Register use pattern on official label

Lab animal metabolism studies

Plant

metabolism

Farm animal

metabolism

identity

of the

residue

Supervised field trials - measure

residues resulting from use pattern