Regulatory requirements multiple exposures

Current regulatory requirements and chemical product warnings, for the most part, address the single chemicals in the product being addressed. There are no requirements for the consideration of the context in which the product can be reasonably expected to be used and the multiple exposures that may ensue. Benzene use provides an example. 

The 1,2-D/1,3-D study discovered several cases where chloroform, carbon tetrachloride, and TCE were detected together with DBCP or 1,2-D in a single sample. Should a regulatory action level for a single toxic chemical be revised when other chemicals, particularly carcinogens, are also present More stringent safety factors may be required for deriving adequately protective water quality standards when multiple exposure to a mixture of two or more chemicals is involved. 

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