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Environmental Health - Toxic Substances

Investigations

Frequently Asked Questions

Which chemical compounds did you find most often?
The most frequently detected compounds (those that were found in more than half the streams samples) were: coprostanol (85.7%, a fecal steroid, a natural part of human and animal waste), cholesterol (84.3%, a plant and animal steroid also widely naturally occurring), N-N-diethyltoluamide (74.1%, insect repellent), caffeine (70.6%, a stimulant), tri(2-chloroethyl)phosphate (57.6%, a fire retardant), triclosan (57.6%, an antimicrobial disinfectant), and 4-nonylphenol (50.6%, a nonionic detergent metabolite).

In broader terms, steroidal compounds were found in 89% of the streams followed by nonprescription drugs (81%), an insect repellant (74%), detergent metabolites (69%), disinfectants (66%), plasticizers (64%), fire retardants (60%), antibiotics (48%), insecticides (45%), polycylic aromatic hydrocarbons (44%), reproductive hormones (40%), other prescription drugs (32%), antioxidants (29%), fragrances (27%) and a solvent (24%).




 

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Page Last Modified: Tuesday, 04-Aug-2015 15:34:39 EDT