The Chemical Residue Surveillance Program for Foods

Background

The chemical residue surveillance program of the Canadian Food Inspection Agency (CFIA) consists of three well-defined components. The first is monitoring sampling, which probes the food supply for potential contamination and is managed under the National Chemical Residue Monitoring Program (NCRMP). The second is directed sampling which focuses on identified chemical contamination issues and the third is compliance sampling, which seeks removal of food in violation of standards from the marketplace.

The National Chemical Residue Monitoring Program (NCRMP) has been in place since 1978.. This program produces essential residue information, required to show consumers that the Canadian food supply is safe. It provides data allowing for the statistical determination of contamination and the estimation of whether or not the level of those contaminants poses a potential risk to consumers, over the long term. The information is provided to Health Canada and its Agencies in order that they are able to establish new standards for foods and review the existing standards for their ongoing appropriateness. In addition, monitoring allows for the identification of food producers distributing items in violation of standards in the Canadian marketplace. This allows for directed corrective interventions with such individuals and companies using the tools of the directed and compliance sampling programs.

The NCRMP consists of a comprehensive plan that leads to a statistically randomized sampling schedule. The CFIA develops the plan and schedule using criteria described in two publications of the Codex Alimentarius Commission (CAC). These are produced as joint publications of the Food and Agricultural Organization of the United Nations (FAO) and the World Health Organization (WHO).

1 - "Pesticide Residues in Food", Joint FAO/WHO Food Standards Programme, Volume 2, 2nd edition, 1993 and

2 - "Residues of Veterinary Drugs in Foods", Joint FAO/WHO Food Standards Programme, Volume 3, 2nd edition, 1995

The NCRMP is designed to focus on and select foods for testing, on the basis of estimated risk. As such, food items consumed in greater quantities by Canadians, those that are more contaminated or those, which are contaminated with more toxic components, are sampled and tested in the greatest numbers. The sampling plan leads to a well defined sampling schedule which identifies to CFIA operations staff the time and place that a sample is to be taken and the accredited laboratory which is to receive the sample and test it according to a schedule provided by the FMCE Division. The schedule will also identify to the laboratories the commodity types that are scheduled for submission to their facilities during the year, the time of year that the sample is to be expected and the tests to be completed on those sample submissions.

This NCRMP data is also critical to the continued acceptance of foods from Canada in the international marketplace. Test results and testing plans are shared annually with responsible officials in other nations as a precondition to unfettered trade with those nations.

Because the test results impact directly on the long term health and safety of Canadian and foreign consumers and the ongoing acceptance of food exports from Canada in international trade, it is essential that strict adherence to all quality criteria is practised by all food samplers and laboratory analysts.

Components of the Chemical Residue Surveillance Program for Foods

Monitoring or data gathering is designed to provide profile information on the occurrence of chemical residues, food additives and microbiological organisms in predefined sampling populations. Monitoring information is normally obtained through a statistically based selection of random samples from normal appearing populations. The sampled lots are not held and are usually passed into consumer channels before the results are known. No direct enforcement action is taken on the basis of monitoring alone.

Directed sampling is to verify any suspected problems of potential health risk, suggested in the monitoring program and is directed at targeted populations (e.g. commodity types or geographical areas). This component verifies violations of Canadian Acts & Regulations and triggers further inspections as part of compliance action. If warranted, product is detained until test results indicate the appropriate course of action. The approach for directed sampling is referred to as biased or directed, and follows Codex Alimentarius specifications. Directed sampling results leading to further compliance action (violative results) must be verified by prescribed confirmatory techniques before any follow-up control action is taken. Education is an important element in correcting identified problems.

Compliance action is taken as a regulatory control measure to prevent the marketing or remove from the market a contaminated or adulterated food product. It presupposes that enforceable regulations or guidelines relevant to the situation are in existence. The compliance action is always directed at a specific source, (i.e. the party felt to be legally responsible). The product is detained until the test results indicate the appropriate disposition. The approach for compliance testing is referred to as in-depth sampling and follows Codex Alimentarius specifications. The establishment of a chain of custody of the sample is essential if legal proceedings are expected to ensue.

Special or pilot surveys are used to gather information about the occurrence of residues not meeting the requirement of the other program components, above. For example, initial surveys or surveys for components outside of the health and safety criteria such as feed mix up might be included here. These are usually limited in scope and duration.

Blitzes are used to obtain a snapshot in time at some point during the fiscal year. The scheduling of blitzes is unannounced. A blitz may allow for the sampling of every herd presented for slaughter for a specified, usually short, period of time not exceeding 2 to 6 weeks.

Legal sampling is undertaken for specific conditions where legal action is the anticipated follow up action. Certain additional criteria are demanded during the sampling submission and laboratory testing of these samples. Adherence to all quality assurance is essential. Legal advice should be sought prior to the initiation of such activities.

Implementation of the Chemical Residue Surveillance Programs

The requirements of the monitoring portion of the NCRMP are developed with input from the CFIA commodity program groups. The sampling information is forwarded to the CFIA operations in a very detailed format. It specifies the date, time, commodity, species, tissues, country of origin, testing facility and pre assigned sample number for every submission.

For non scheduled follow up samples or samples taken at the discretion of the inspector a Food Product Sampling Report form must be completed and submitted with the sample to the receiving laboratory responsible for the testing. The inspector has the authority to select a sample whenever there is reasonable suspicion of a problem.

Laboratory result availability

One of the reasons that the CFIA, in its Residue Plan Design, categorizes the program components by designations such as monitoring, directed sampling, compliance, special and pilot surveys, blitzes and legal sampling is to maximize laboratory testing capacity. Samples for which there is higher likelihood of finding a positive have a shorter turnaround time in order to facilitate follow up actions. Thus for surveillance, compliance and special request samples generated at the inspectors discretion the reporting time is 5, 3 and 3 days respectively, including transit time to laboratory.

For samples generated as a result of blitzes and pilot surveys reporting times are longer. Blitzes are held at the laboratory until all the samples are collected, typically 2 to 6 weeks, and then analysis proceeds as rapidly as possible until all samples are completed. Pilot and special surveys usually are reported within 90 days of sampling.

For monitoring samples reporting time is dependent on the type of residue being tested. It ranges from 3 days for antibiotics to 45 days for toxic metals and elements. The average for monitoring samples is 21 calendar days.

Enforcement actions and records available

The CFIA reviews each violation and appropriate action is requested, as necessary. Such action includes; the notification of program and operation divisions within the CFIA to initiate follow up inspections. These activities are initiated, tracked and closed using the Residue, Anti-Microbial and Micro-Organism System (RAMS). If there is still product on the marketplace a Food Recall will be initiated. This recall will be classified and managed in a manner consistent with the level of risk associated with consumption of the food items.

If the violation is feed related, the on farm follow up inspections would be requested. Feed inspectors, possibly with assistance from provincial agriculture personnel would carry out an on farm investigation, notifying the producer of the violation, identifying any actions on future shipments and advising on means to avoid further violations. In the case of a violation believed to be due to drug injections, notification is similar except an animal health inspector will conduct the on farm follow up inspection.

If a prohibited drug is involved, in addition to the above actions, Health Canada's Veterinary Drugs Directorate will be advised and the assistance of the Drug Enforcement Division of Health Canada will be requested. This group might investigate the sources and distribution of the illegal drug product.