Health-Based Guidance Values for Priority Substances

Guidance values are intended to form, in part, the basis for development of reference points against which the quality of various environmental media can be judged. They were developed on the basis of information reviewed for assessments conducted for substances on the Priority Substances List under the Canadian Environmental Protection Act

These guidance values are derived solely from assessment of toxicological and epidemiological data for the ingestion and inhalation routes of exposure and take into consideration potential effects on human health only. Although dermal contact may, in some cases, also contribute significantly to total exposure to environmental contaminants, this route has not been addressed herein, due principally to limitations of the available data that serve as a basis for development of health-based guidance in this area.

It should also be emphasized that the guidance values do not take into account any considerations related to risk management, such as feasibility of attainment or costs of measurement and control.

Health-based guidance values for substances on the First Priority Substances List (HTML) and Second Priority Substances List (HTML) can be downloaded. Hard copies are available from ExSD@hc-sc.gc.ca.