Environmental Health - Toxic Substances Hydrology Program
U.S. Geological Survey (USGS) and U.S. Environmental Protection Agency (EPA) scientists have shown that wastewater treatment plants are a significant source of pharmaceuticals and other emerging contaminants to rivers. A recent study analyzed treated wastewater being discharged to rivers from 10 wastewater treatment plants (sewage treatment plants) for 110 emerging contaminants, and found between 28 and 50 of these compounds in the wastewater. Commonly detected compounds included antimicrobial disinfectants (triclosan), antibiotics (sulfamethoxazole), musk fragrances (tonalide), antihistamines (diphenhydramine), and antiepileptic drugs (carbamazepine). After analyzing water-quality samples that were collected upstream and downstream of the treatment plants, the scientists determined that wastewater treatment plants are a significant source of emerging contaminants in the streams that were sampled.
This study and others provide evidence that many emerging contaminant compounds may make ideal tracers and indicators of wastewater in rivers and other water bodies because they are used only by humans. For example:
Glassmeyer, S.T., Furlong, E.T., Kolpin, D.W., Cahill, J.D., Zaugg, S.D., Werner, S.L., Meyer, M.T., and Kryak, D.D., 2005, Transport of chemical and microbial compounds from known wastewater discharges – Potential for use as indicators of human fecal contamination: Environmental Science and Technology, v. 39, no. 14, p. 5157-5169, doi: 10.1021/es048120k.
Verplanck, P.L., Taylor, H.E., Nordstrom, D.K., Barber, L.B., 2005, Aqueous stability of gadolinium in surface waters receiving sewage treatment plant effluent, Boulder Creek, Colorado: Environmental Science and Technology, v. 39, no. 18, p. 6923-6929, doi: 10.1021/es048456u.
** North American Shale Composite (NASC) – The North American Shale Composite is a standard reference sample composed of 40 different shales, some of which are from Africa and Antarctica. Scientists use the NASC to compare results of elemental analysis of rocks and water samples against the know analysis of the standard.
Gromet, L.P., Dymek, R.F., Haskin, L.A., and Korotev, R.L., 1984, The "North American Shale Composite:" its compilation, major and trace element characteristics. Geochimca et Cosmochimica Acta, v. 48, p. 2469-2482.