Regulatory Use of Generic Exposure Data for Pest Control Products: The Canadian Perspective

Abstract

Health Canada’s Pest Management Regulatory Agency (PMRA) is responsible for the federal regulation of pesticides in Canada. According to the Pest Control Products Act, companies intending to sell pest control products in Canada must provide data demonstrating the safety of these products to both human health and the environment, and also that these products have value when used according to label directions. Only pest control products that have acceptable risk are registered for use in Canada. The PMRA data requirements for human health risk assessments include toxicology studies to characterize the hazard profile of a pesticide and studies to assess the degree and nature of exposure to specific human populations, such as workers and children. As the science of risk assessment has evolved, so too have the regulatory requirements for exposure studies. While the protocols of chemical-specific exposure studies are typically required to adhere to established guidelines, variations between study protocols have limited the ability to use the data in a more generic fashion. Furthermore, differing policies on the requirements and use of these studies have sometimes led to differences in interpretation between regulatory agencies. As such, experts, working in conjunction with regulatory agencies and researchers, have developed the scientific methodology that allows exposure studies conducted with one pesticide to be used for the assessment of many pesticide active ingredients in a generic manner, such as handler exposure studies. The availability of scientifically robust studies that can be used in a generic manner has enabled the development and standardization of protocols and the generation of human exposure data that is applicable to a wide variety of pesticide scenarios and submissions. Much of the generic exposure data has been developed by the exposure task forces who have incorporated regulatory input throughout the process in a collaborative and scientific manner. Overall, this has resulted in a large, comprehensive, and modern collection of data, and has been an efficient mechanism for developing data required for pesticide submissions. It has also allowed pesticide regulatory authorities, such as the PMRA, to use these studies, when applicable, in lieu of chemical-specific data.