Numerous studies have shown that a variety of manufactured and natural
organic compounds such as
pharmaceuticals,
steroids,
surfactants, flame retardants,
fragrances,
plasticizers and other chemicals often associated with wastewaters have been detected in the vicinity of municipal wastewater discharges and livestock agricultural facilities. To provide new data and insights about the environmental presence of some of these chemicals in untreated sources of drinking
water in the United States targeted sites were sampled and analyzed for 100 analytes with sub-parts per billion detection capabilities. The sites included 25 ground- and 49 surface-water sources of drinking
water serving populations ranging from one family to over 8 million people. Sixty-three of the 100 targeted chemicals were detected in at least one
water sample. Interestingly, in spite of the low detection levels 60% of the 36
pharmaceuticals (including
prescription drugs and
antibiotics) analyzed were not detected in any
water sample. The five most frequently detected chemicals targeted in surface
water were:
cholesterol (59%, natural
sterol),
metolachlor (53%,
herbicide),
cotinine (51%,
nicotine metabolite),
beta-sitosterol (37%, natural
plant sterol), and 1,7-dimethylxanthine (27%,
caffeine metabolite); and in ground
water:
tetrachloroethylene (24%,
solvent),
carbamazepine (20%,
pharmaceutical), bisphenol-A (20%,
plasticizer), 1,7-dimethylxanthine (16%,
caffeine metabolite), and
tri (2-chloroethyl)
phosphate (12%, fire retardant). A
median of 4 compounds were detected per site indicating that the targeted chemicals generally occur in mixtures (commonly near detection levels) in the environment and likely originate from a variety of animal and human uses and waste sources. These data will help prioritize and determine the need, if any, for future occurrence, fate and transport, and health-effects research for subsets of these chemicals and their degradates most likely to be found in
water resources used for drinking
water in the United States.
