Testing for PPCPs and EDCs

Testing for PPCPs and EDCs in Your Water

Every day millions of gallons of treated and untreated wastewater are discharged into the waterways of the world. This wastewater may contain varying concentrations of pharmaceuticals and personal care products (PPCPs) including prescription and over the counter medications, nutraceuticals, illicit drugs, detergents, perfumes, insect repellent, sunscreens, and steroids, some of which have been identified in a recent article by The Associated Press1.

Recent studies have shown that many of these PPCP compounds at low concentrations can have negative effects on the endocrine systems of aquatic organisms. These compounds are collectively known as Endocrine Disrupting Compounds (EDCs). Other concerns regarding PPCPs include contamination of drinking water, estrogenic effects on humans and wildlife, and development of antibiotic resistant bacteria.

In 1999 and 2000, a study was performed by the USGS (Koplin, et al, 20002) in which the concentrations of 95 of these compounds were measured in 139 streams in 30 states (mostly downstream from intense urbanization and livestock production). Eighty-two of the 95 compounds of interest were found and 80% of the streams tested contained one or more of these compounds. Multiple compounds were found in many samples. The average number was seven and the greatest number was 38. Concentrations were low, rarely exceeding health advisories or aquatic-life criteria. However, advisory limits are not available for many of these compounds. Little is known about the effects of long-term low exposure to these compounds, potential interactions with other compounds in the environment (synergistic or antagonistic), possible cumulative effects over time, or what effect any degradation products of these compounds may have.

These compounds enter the environment from a wide variety of sources including agriculture use of pesticides and antibiotics, industrial discharges, and household use of chemicals and pharmaceuticals. Most wastewater treatment and domestic septic systems are not designed to remove these compounds. In another USGS study (Stackelberg et al., 20043), between 11 and 17 of these compounds were found in all finished drinking water samples at a conventional water treatment plant.

Analytical testing for these compounds requires the use of sophisticated instrumentation and experienced chemists. Due to their chemical nature, many of these compounds are not amenable to standard environmental gas chromatographic (GC) techniques. They are generally larger, less volatile, and more polar than other organic compounds that can be analyzed via GC and GC/MS techniques. Some of these compounds are also thermally labile, breaking down at elevated GC temperatures. Since PPCPs include many different classes of compounds with varying physical and chemical properties, Liquid Chromatography/Mass Spectroscopy/Mass Spectroscopy (LC/MS/MS) provides a convenient approach for determining a relatively wide range of chemicals of interest.

1. Donn, Jeff, Mendoza, Martha, and Pritchard, Justin, AP Probe Finds Drugs in
   Drinking Water, The Associated Press, March 9, 2008.
2. Kolpin, D.W., Furlong, E.T., Meyer, M.T., Thurman, E.M., Zaugg, S.D., Barber,
   L.B., and Buxton, H.T., 2002, Pharmaceuticals, hormones, and other organic
   wastewater contaminants in U.S. streams, 1999-2000: A National reconnaissance:
   Environmental Science and Technology, v. 36, no. 6, pages 1202-1211.
3. Stackelberg, P., Furlong, E., Zaugg, S., Meyer, M., Gibs, J., and Lippincott, R..L., 2004,
   Fate of organic wastewater related contaminants in a drinking water treatment
   plant in Proceedings of the 4th International Conference on Pharmaceuticals and
   Endocrine Disrupting Chemicals in Water, Minneapolis, Minn., National Ground
   Water Association, October 13-15, 2004, CD-ROM, p. 17-18.