What is the issue?

Legislation such as the Canadian Environmental Protection Act has helped to significantly reduce the amount of toxic chemicals entering the Canadian environment. However, Canadian ecosystems and organisms continue to be exposed to potentially harmful levels of many toxic pollutants, including persistent organochlorine compounds. As persistent contaminants can accumulate at high concentrations in the tissues of wildlife, Canadians— particularly northern Canadians—who rely on locally harvested food are at greater risk from these toxic chemicals.

Minute concentrations of toxic contaminants adhering to inhalable airborne particles can be absorbed deep into the lungs. Thus, toxics in air, particularly urban air, are also a threat to human health.

What do we know?

Every year, approximately 6 million tonnes of hazardous waste are generated in Canada. In addition, hazardous waste is imported into Canada: total imports increased from 383 000 tonnes in 1994 to 663 000 tonnes in 1999. Although over 70% of these imports were destined for recycling in 1994, only 40% went to recycling operations in 1999.

The presence of toxic contaminants in the soil, water, and air is the subject of selected monitoring and research. A particular focus has been top predators, such as eagles, Herring Gulls, Great Blue Herons, Polar Bears, and the Beluga (White Whale).

Double-crested Cormorants, fish-eating birds at the top of the food chain, are an important indicator of toxic contamination. Concentrations of DDE (a derivative of the pesticide DDT) in Double-crested Cormorant eggs have declined between 70% and 91% since the early 1970s in sampling sites across southern Canada. The decline levelled off in the 1990s, perhaps because of the slow release of contaminant residues from bottom sediments or the long-range atmospheric transport of the pollutant from countries still using DDT.

Similarly, concentrations of polychlorinated biphenyls, or PCBs, in eggs of Double-crested Cormorants have declined between 68% and 78% since the early 1970s. The inconsistent trends in the 1990s may be due to the release of PCBs still in use, the continued escape of PCBs from storage and dump sites, and the long-range transport of PCBs from other countries.

What do we need to know?

The sources of toxic contaminants must be determined, and a full understanding is needed of how these contaminants actually enter the environment. Pesticides are a major source of persistent organic pollutants, including the dozens of chemical compounds that are intentionally released into the environment to serve as herbicides, insecticides, fungicides, and rodenticides. Other sources are emissions from vehicles and industries and releases through the use of solvents and other industrial compounds. A fuller understanding of the impacts of all of these pollutants on the health of humans and other living organisms is needed.

•  Download Concentrations of DDE and PCBs in Double-crested cormorant eggs 1970-1998(MS-Excel)
• Concentrations of DDE and PCBs in Double-crested cormorant eggs 1970-1998

What are we doing based on the information we have?

Regulations have been adopted in Canada over the past two decades to ban the use of organochlorine compounds or to severely restrict their release into the environment. The risk continues, however, because of the slow release of residual chemicals and the long-range transport of air pollutants from other countries still using toxic substances banned in Canada. More recent Canadian actions to address this issue include, for example, a section of the Canadian Environmental Protection Act, 1999 that addresses virtual elimination of PCBs, DDT, and certain other substances. The Canadian Environmental Protection Act, 1999 also provides enhanced authority to control the export and import of hazardous waste, whether it is destined for final disposal or recycling.

In 1998, Canada signed an international Persistent Organic Pollutants Protocol to reduce atmospheric emissions of DDT, PCBs, and 14 other persistent organic pollutants. The agreement was negotiated under the auspices of the United Nations Economic Commission for Europe, which includes Canada, the United States, and countries of Europe and the former Soviet Union. It is the first major multinational, legally binding agreement to place controls on emissions of these hazardous pollutants.

Negotiation of a global Convention of Persistent Organic Pollutants (POPs) under the United Nations Environment Programme were completed in December 2000. The draft convention sets out control measures covering the production, import, export, disposal, and use of 12 of these pollutants. It calls for the promotion of the best available technologies and practices for replacing existing uses of POPs while preventing the development of new ones. The 122 Countries involved in the negotiations are to draw up national implementation strategies and develop action plans for carrying out their commitments. Canada played a leadership role in developing this draft convention. The Convention will be formally adopted at a Conference in Stockholm, May 2001, and will enter into force when ratified by 50 countries, a process that is expected to take about four years.

Further information

For additional information on toxic chemicals, please refer to the following*:

Environment Canada:

• Atlantic Region toxic chemicals:
  www.ns.ec.gc.ca/pollution/toxichemical.html
  
  
• Environmental indicator bulletin on toxic contaminants:
  www.ec.gc.ca/ind/English/Toxic/default.cfm
  
  
• National Wildlife Toxicology Program:
  www.cws-scf.ec.gc.ca/nwrc/wildtox.htm
  
  
• Ontario Region pollution prevention web site:
  www.on.ec.gc.ca/pollution/
  
  
• PCBs in cormorant eggs in British Columbia:
  www.ecoinfo.org/env_ind/region/cormorant/pcbs.htm
  
  
• Prairie and Northern Region Toxic Substances Division:
  www.mb.ec.gc.ca/pollution/e00s26.en.html
  
  
• Quebec Region wildlife ecotoxicology:
  www.qc.ec.gc.ca/faune/faune/html/ecotoxicology.html
  
  
• Government of British Columbia toxic contaminants indicator:
  wlapwww.gov.bc.ca/soerpt/15-glance.html
  
  
• Toxic Substances Research Initiative:
  www.hc-sc.gc.ca/ehp/ehd/tsri/index.htm
  
  

*Note: Information found on some sites is presented only in the language in which it was written. We apologize for any inconvenience.