Over the years one of the highest risks of exposure to hazardous chemicals has been in the work environment. The Center for Disease Control (CDC) has developed a list of the top priority substances to be aware of. This priority list is not a list of “most toxic” substances, but rather a prioritization of substances based on a combination of their frequency, toxicity, and potential for human exposure. The complete CDC list contains 275 substances including Arsenic, Lead, Mercury, Benzene, Cyanide and Asbestos.

