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Environmental Health - Toxic Substances


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