Scientific Investigations Report 2012–5106
Concern over the presence of contaminants of emerging concern, such as pharmaceutical compounds, hormones, and organic wastewater compounds (OWCs), in waters of the United States and elsewhere is growing. Laboratory techniques developed within the last decade or new techniques currently under development within the U.S. Geological Survey now allow these compounds to be measured at concentrations in nanograms per liter. These new laboratory techniques were used in a reconnaissance study conducted by the U.S. Geological Survey, in cooperation with the Pennsylvania Department of Environmental Protection, to determine the occurrence of contaminants of emerging concern in streams, streambed sediment, and groundwater of Pennsylvania. Compounds analyzed for in the study are pharmaceuticals (human and veterinary drugs), hormones (natural and synthetic), and OWCs (detergents, fragrances, pesticides, industrial compounds, disinfectants, polycyclic aromatic hydrocarbons, fire retardants and plasticizers). Reconnaissance sampling was conducted from 2006 to 2009 to identify contaminants of emerging concern in (1) groundwater from wells used to supply livestock, (2) streamwater upstream and downstream from animal feeding operations, (3) streamwater upstream from and streamwater and streambed sediment downstream from municipal wastewater effluent discharges, (4) streamwater from sites within 5 miles of drinking-water intakes, and (5) streamwater and streambed sediment where fish health assessments were conducted.
Of the 44 pharmaceutical compounds analyzed in groundwater samples collected in 2006 from six wells used to supply livestock, only cotinine (a nicotine metabolite) and the antibiotics tylosin and sulfamethoxazole were detected. The maximum concentration of any contaminant of emerging concern was 24 nanograms per liter (ng/L) for cotinine, and was detected in a groundwater sample from a Lebanon County, Pa., well.
Seven pharmaceutical compounds including acetaminophen, caffeine, carbamazepine, and the four antibiotics tylosin, sulfadimethoxine, sulfamethoxazole, and oxytetracycline were detected in streamwater samples collected in 2006 from six paired stream sampling sites located upstream and downstream from animal-feeding operations. The highest reported concentration of these seven compounds was for the antibiotic sulfamethoxazole (157 ng/L), in a sample from the downstream site on Snitz Creek in Lancaster County, Pa.
Twenty-one pharmaceutical compounds were detected in streamwater samples collected in 2006 from five paired stream sampling sites located upstream or downstream from a municipal wastewater-effluent-discharge site. The most commonly detected compounds and maximum concentrations were the anticonvulsant carbamazepine, 276 ng/L; the antihistamine diphenhydramine, 135 ng/L; and the antibiotics ofloxacin, 329 ng/L; sulfamethoxazole, 1,340 ng/L; and trimethoprim, 256 ng/L.
A total of 51 different contaminants of emerging concern were detected in streamwater samples collected from 2007 through 2009 at 13 stream sampling sites located downstream from a wastewater-effluent-discharge site. The concentrations and numbers of compounds detected were higher in stream sites downstream from a wastewater-effluent-discharge site than in stream sites upstream from a wastewater-effluent-discharge site. This finding indicates that wastewater-effluent discharges are a source of contaminants of emerging concern; these contaminants were present more frequently in the streambed-sediment samples than in streamwater samples. Antibiotic compounds were often present in both the streamwater and streambed-sediment samples, but many OWCs were present exclusively in the streambed-sediment samples. Compounds with endocrine disrupting potential including detergent metabolites, pesticides, and flame retardants, were present in the streamwater and streambed-sediment samples. Killinger Creek, a stream where wastewater-effluent discharges contribute a large percentage of the total flow, stands out as a stream with particularly high numbers of compounds detected and detected at the highest concentrations measured in the reconnaissance sampling.
Nineteen contaminants of emerging concern were detected in streamwater samples collected quarterly from 2007 through 2009 at 27 stream sites within 5 miles of a drinking-water intake. The number of contaminants and the concentrations detected at the stream sites within 5 miles of drinking-water intakes were generally very low (concentrations less than 50 ng/L), much lower than those at sites downstream from a wastewater-effluent discharge. The most commonly detected compounds and maximum concentrations were caffeine, 517 ng/L; carbamazepine, 95 ng/L; sulfamethoxazole, 146 ng/L; and estrone, 3.15 ng/L. The concentrations and frequencies of detection of some of the contaminants of emerging concern appear to vary by season, which could be explained by compound use, flow regime, or differences in degradation rates. Concentrations of some contaminants were associated with lower flows as a result of decreased in-stream dilution of wastewater effluents or other contamination sources.
Twenty-two contaminants of emerging concern were detected once each in streamwater samples collected in 2007 and 2008 from 16 fish-health stream sites located statewide. The highest concentrations were for the OWCs, including flame retardants tri(2-butoxyethyl)phosphate (604 ng/L) and tri(2-chloroethyl)phosphate (272 ng/L) and the fragrance isoquinoline (330 ng/L). Far fewer numbers of contaminants of emerging concern were detected at the fish-health sites than at the wastewater-effluent-discharge sites. Most of the fish-health sites were not located directly downstream from a wastewater-effluent discharge, but there were multiple wastewater-effluent discharges in the drainage basins upstream from the sampling sites. No distinct pattern of contaminant occurrence could be discerned for the fish-health stream sites.
First posted August 1, 2012
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Reif, A.G., Crawford, J.K., Loper, C.A., Proctor, Arianne, Manning, Rhonda, and Titler, Robert, 2012, Occurrence of pharmaceuticals, hormones, and organic wastewater compounds in Pennsylvania waters, 2006–09: U.S. Geological Survey Scientific Investigations Report 2012–5106, 99 p.
Purpose and Scope
Categories of Contaminants of Emerging Concern
Potential Sources of Contaminants of Emerging Concern
Other Potential Sources of Contaminants of Emerging Concern
Pharmaceutical Manufacturing Facilities
Land Application of Biosolids
Combined Sewer Overflows
On-Site Wastewater Systems
Previous and Current Investigations
Site Selection and Sampling Locations
Wells in Agricultural Areas Used to Supply Livestock
Streams Draining Areas with Animal-Feeding Operations
Streams Receiving Municipal Wastewater Effluents
Stream Sites near Drinking-Water Intakes
Stream Sites Used to Evaluate Fish Health
Streamflow Measurement and Water-Quality Characteristics
Collection and Processing of Water-Quality Samples
Antibiotics and Ibuprofen
Organic Wastewater Compounds
Antibiotics and Ibuprofen
Organic Wastewater Compounds
Quality Assurance and Quality Control
Quality Control for Field Measurements
Quality Control for Streamwater and Streambed-Sediment Samples
Pharmaceuticals, Hormones, and Organic Wastewater Compounds in Pennsylvania Waters
Compounds in Groundwater Used to Supply Livestock
Compounds in Streamwaters Upstream and Downstream from Animal-Feeding Operations
Compounds in Streamwater and Streambed Sediments Upstream and Downstream from Wastewater Discharges
2006 Sampling Upstream and Downstream from Wastewater-Effluent-Discharge Sites
2007 to 2009 Sampling Downstream from Wastewater-Effluent Discharges
Compounds in Streamwaters near Drinking-Water Intakes
Patterns of Contaminant Occurrence
Number of Permitted Discharges
Compounds in Streamwaters and Streambed Sediment at Fish-Health Sites
Compounds in Streamwater
Compounds in Streambed Sediment
Implications of Contaminants of Emerging Concern in Pennsylvania Waters
Implications for Ecosystem Health
Implications for Contaminants in Source Waters for Public Drinking-Water Supplies
Appendix A. Summary of laboratory methods
Appendix B. Summary of duplicate sample results
Appendix C. Reagent-spiked and laboratory-spiked sample results