Relative toxicity is key to health impacts

Examining the toxicity of hazardous substances-and not just how much is released into the environment-is crucial to assessing the effects of industrial chemicals on children's health, says a new report by the Commission for Environmental Cooperation of North America. The report says data on the release and transfer of toxic pollutants should be used in combination with biomonitoring to provide a more complete picture of children's potential exposure to these substances. The report ranks and compares chemicals on the U.S. Toxics Release Inventory and Canada's National Pollution Release Inventory. Using toxicity equivalencies, the report finds that among carcinogens emitted to the air, carbon tetrachloride and lead and its compounds pose the greatest hazards to human health, although styrene and acetaldehyde are released in the greatest amounts. For chemicals recognized as adversely affecting human development and reproduction, mercury and lead compounds posed the greatest hazards, although toluene and carbon disulfide are released to the air in the largest quantities, the report says.