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Canadian Regulatory Approach for Establishing MRLs

World Trade Organization Workshop on Maximum Residue Levels October 25, 2016

Dr. Peter Chan, Director General Health Evaluation Directorate Management Regulatory Agency Health Canada Risk Assessment Framework

Toxicology Exposure • Identify Hazards • Identify Dose with No Adverse • Identify routes of exposure Effect • Quantify the Level of • Establish Acceptable Level Exposure of Human Exposure

Risk Assessment

Acceptable?

Risk Mitigation/ Management

Approve only those uses that meet HC standards

2 What are Maximum Residue Limits (MRLs)

• Maximum amount of pesticide residue legally permitted to remain on food sold in Canada (based on residues expected in/on a food at time of harvest) for both domestic or imported food. . Specified under the Products Act for the purposes of the adulteration provision of the Food and Drugs Act . Serves as enforcement tool for compliance with the Canadian registered pesticide label (enforced by the Canadian Food Inspection Agency) • MRLs are set for each pesticide/ combination

3 MRL Setting Process

4 What are Crop Field Trials?

• As per the draft OECD guidance document1: “Crop field trials (also referred to as supervised field trials) are conducted to determine the magnitude of the pesticide residue in or on raw agricultural commodities, including feed items, and should be designed to reflect pesticide use patterns that to the highest possible residues. Objectives of crop field trials are to: 1. Quantify the expected range of residue(s) in crop commodities following treatment according to the proposed or established Good Agricultural Practice (GAP); 2. Determine, when appropriate, the rate of decline of the residue(s) of plant protection product(s) on commodities of interest; 3. Determine residue values such as the Supervised Trial Median Residue (STMR) and Highest Residue (HR) for conducting dietary risk assessment and calculation of the dietary burden of livestock; and 4. Derive maximum residue limits (MRLs).”

• MRLs are then calculated by entering residue data from the crop field trials into the OECD calculator, which generates a statistically robust and scientifically-defensible MRL value in the region of the 95th percentile of the underlying residue distribution (conservative).

http://www.oecd.org/env/ehs/testing/GD%20CFT_31%20March%202016.pdf

5 Dietary Exposure Assessment

Components

Consumption: Residue: Consumption Amount & types of Concentration of the Information food consumed in a substance in foods • Representative of all given period of time populations - All geographical areas, all ethnic groups, all age groups, both sexes; monitoring across all seasons; large number of respondents

• US National Health and Nutritional Examination Residue Survey, What We Eat in America (NHANES,WWEIA) X Consumption dietary survey (2005-2010) = Dietary Exposure

6 Assessing Dietary Risk

Dietary Risk: • Estimate Potential Daily Intake (PDI) for various subpopulations and age groups, including infants, toddlers, children, adults and seniors. • Includes residues in food from both domestic and imported sources. • Can use Tier approach to refine dietary risk assessment.

Acceptable Risk: • Dietary risk acceptable if PDI does not exceed the Acceptable Daily Intake (ADI) and/or Acute Reference Dose (ARfD)*

* ADI/ARfD = No Observable Adverse Effect Level Uncertainty Factors (X PCPA Factor)

7 Contribution of Residues to Dietary Risk Assessment

8 Approaches to risk assessment and risk management where international standards are not used

International standards may not be aligned (for the same pesticide/commodity combination) when:  Data packages are different;  Residue definitions are different;  Environmental conditions and pest pressures are different leading to different application rates, different cGAPs, hence different MRLs;  Methodologies for calculating MRLs are different ;  Criteria/legislative authorities for setting MRLs are different ;  Dietary and cultural preferences which determine the eaten in different regions (different dietary intake) are different. Approaches to risk assessment and risk management where international standards are not used – Cont’d

• Where a tiered approach has been used for the dietary risk assessments (Tier I: MRLs; Tier II: field trial data and Tier III: food monitoring data) and there remains risks of concern, MRLs must be established at the Limit of Quantitation (LOQ) of the enforcement method. Moving Forward – Some Suggestions to minimize trade irritants • Growers: – Communicate their needs to registrants regarding crop/product, export market and anticipated growth in new export markets – Be aware of MRLs in other countries before shipping based in registration status, labels, pests, use patterns, etc. • Industry: – Globally harmonizing GAPs for global supervised residue trials – Make Joint Review Submissions – Consider domestic registrations in key export markets – Submit same data package globally • Regulatory Authorities: – Participate in Global Joint Reviews and Science Policies development – Avoid instituting new regulatory burdens – Continue to contribute to Codex (JMPR/CCPR) activities

11 Questions?

12