What is inherently Toxic to non-human organisms?
The term “inherently Toxic” has been proposed and used under CEPA 1999 to distinguish from the word “toxic,” which is defined under section 64. “Inherently Toxic” refers to the hazard a substance presents to the environment or human health, which can be represented by the toxic effect caused by the substance — i.e., the toxicity found in a study or predicted due solely to the test substance, or the effect that has not been masked or mitigated by some factor or parameter. Environment Canada has chosen to use the results of aquatic toxicity tests to represent the character of “inherently Toxic” to non-human organisms. A common test of aquatic toxicity considered by Environment Canada for categorization is the 96 hour LC50. This test determines the concentration of substance in water that kills 50% of the organisms (e.g. water fleas).
