Dana Kolpin: US Geological Survey

Environmental Side Effects Symposium Plenary lecture:
"Pharmaceuticals, EDCs, and Other Organic Wastewater Contaminants in Water Resources of the US"
20 September 2004

Since 1998, the U.S. Geological Survey (USGS) has been developing analytical capabilities to measure pharmaceuticals and other organic wastewater contaminants (OWCs) in the environment.

Currently, the USGS can analyse more than 140 OWCs using a variety of LC/MS and GC/MS techniques. To date, over 500 samples from across the United States, representing a wide range of climatic and hydrologic conditions, have been analysed for OWCs.

Some of the most frequently detected compounds included cholesterol (plant and animal steroid), DEET (insect repellent), caffeine (stimulant), triclosan (antimicrobial disinfectant), and tri(2-chloroethyl)phosphate (fire retardant). Prescription pharmaceuticals and antibiotics also have been commonly detected at ng/L concentrations.

There is now substantial evidence that some of these compounds impact on the health of wildlife, influencing hormonal and reproductive functions. Dana's seminar will cover research by the U.S. Geological Survey's Toxic Substances Hydrology Program.

Early research focused on broad-scale reconnaissance studies, providing the first nationwide data on the occurrence of OWCs in water resources of the United States. These results documented that OWCs are commonly present in streams and, to a lesser extent, aquifers, particularly at sites that are immediately downstream or down gradient of contaminant sources. Detection of multiple OWCs was common, with as many as 38 OWCs being found in a single water sample. These results indicate that synergistic or additive effects from mixtures of OWCs will need to evaluated.

Subsequent research focused on sources of OWCs and their fate and transport. Samples from municipal wastewater treatment plants and animal waste storage lagoons indicate that both human and animal waste can be sources. Early results indicate that concentrations of OWCs generally increase as the percent of streamflow derived from municipal discharges increases. Recent research has shown that bed sediment can also act as a reservoir of pharmaceuticals and other OWCs to the environment.

This address was the plenary lecture for the Environmental Side Effects Symposium held 20 September 2004 at CSIRO Discovery Centre, Canberra.