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Pharmaceutical Manufacturing Facilities as Sources of Pharmaceuticals to the Environment

Why did the USGS conduct this study?

This study was conducted in cooperation with the New York State Department of Environmental Conservation to assess sources of pharmaceuticals and other emerging contaminants to surface water. The goal of USGS research in this area is to provide information on emerging water-quality issues that improves the ability of decision makers to manage and protect our water resources.

How did USGS decide which chemicals to look for?

Initially, this study tested a wide range of emerging contaminants. During the study however, USGS found a limited number of unidentified chemicals at higher concentrations than the chemicals being analyzed in the outflows of 2 of 3 wastewater treatment plants in New York State. Subsequently, USGS identified the chemicals, developed robust methods to measure the presence and concentration of these chemicals, and focused on evaluating the sources and concentrations of those chemicals.

This forensic approach is being used to investigate additional pharmaceuticals present in these wastewater treatment plant outflows.

Why did USGS select these sites to sample?

The three sites in New York State, which were studied intensively through time, were selected by USGS and NYS Dept of Environmental Conservation as part of an assessment of the impact of wastewater treatment plant outflows on water resources. The sites were selected in New York State because of a mutual interest in the issue and availability of resources from both USGS and NYS Dept of Environmental Conservation. The 23 other wastewater treatment plants studied were selected by USGS to provide a basis for comparison at a national scale.

Would you expect similar results for other streams across the nation?

USGS only tested two wastewater treatment plants that receive a substantial portion of their wastewater from a pharmaceutical manufacturing facility. It is difficult to extrapolate these results to other wastewater treatment plants that receive discharge from pharmaceutical manufacturing facilities. Other facilities may manufacture or package different pharmaceuticals. They may have different practices for handling wastewater. Furthermore, different wastewater treatment types perform differently on different pharmaceuticals. All of these factors indicate that results may vary on a case-by-case basis.

However, the results do demonstrate the need to investigate the potential contributions of pharmaceuticals to the environment from other pharmaceutical manufacturing facilities across the U.S. Ideally, an assessment of the pharmaceuticals lost in the wastewaters of pharmaceutical manufacturing facilities would include direct sampling of those wastewaters. However, that is difficult in many sewer systems and was not possible in this study.

Were you surprised by how high the concentrations of the target pharmaceuticals were?

Yes, we were surprised by these findings. While evidence from an earlier study in India indicated that pharmaceutical manufacturing facilities may be a significant source of pharmaceuticals to the environment, it was commonly believed that good manufacturing practices and the inherent value of the product would limit the loss of pharmaceuticals from pharmaceutical manufacturing facilities. This is the first study in the US that addresses pharmaceutical manufacturing facilities as a source of pharmaceuticals to the environment. One of the lessons of this study is that there is no substitute for environmental data that tests and verifies our theoretical models and hypotheses related to the occurrence and persistence of environmental contaminants.

Are these pharmaceuticals in my drinking water?

USGS has not tested for the presence of these pharmaceuticals in finished drinking water. Now that we know that these pharmaceuticals are found in the environment, we will include them in future drinking water studies.

In this study, USGS found that pharmaceutical levels decreased with distance downstream from the wastewater treatment plan outflow. However, given that these pharmaceuticals are entering streams, it is possible that low levels of some could be present in some drinking-water sources. Drinking water undergoes a variety of treatments before it reaches our tap. Although the treatment processes may not be designed to remove most of these chemicals, many are removed or reduced during treatment.

Do the results of this study indicate that these pharmaceuticals are a threat to human health?

Local and federal regulatory agencies such as the U.S. Environmental Protection Agency and the U.S. Food and Drug Administration have regulatory programs to protect public and ecosystem health, and processes are in place for licensing and regulation of new compounds that might make their way into the environment and establishing standards for drinking water quality. The information provided by this study will support and enhance those activities.

Why did you measure substances for which there is little or no documented information on human or ecological health effects?

USGS has provided information on the presence or absence, and levels and mixtures of many environmental contaminants in various environmental settings and in drinking water, both pre- and post-treatment. This information is essential for prioritizing chemicals for health assessments and conducting those assessments with accurate exposure levels. The information is shared with the Environmental Protection Agency for use in resource management, regulation and chemical registration.

Our goal is to enable environmental assessments, and health effects assessments that use that environmental data, to be conducted on the pharmaceuticals that are most likely to occur in the environment and be of greatest potential health concerns.

Why were the pharmaceuticals detected in only one of 10 reservoirs tested?

Of the 10 reservoirs studied, only five were located downstream of a pharmaceutical manufacturing facility. Two of these five reservoirs are the first downstream reservoir below the outflow of a wastewater treatment plant receiving pharmaceutical manufacturing facility wastewater, and one of these two upstream-most reservoirs had detections of pharmaceuticals.

Several factors affect how far downstream pharmaceuticals will be detected in surface water. These include dilution by inflows from tributary streams and groundwater seepage, and environmental degradation, which can depend on the time of travel downstream and environmental the presence of conditions suitable for degradation.

Are there other mechanisms by which these chemicals get into streams?

There are multiple pathways by which pharmaceuticals can enter the natural environment. These pathways relate primarily to human and animal wastes.

Current understanding is that the largest source of human pharmaceuticals to the environment comes from pharmaceuticals that are consumed and pass through the body. Estimates in the scientific literature indicate that perhaps one quarter to one tenth of that amount comes from disposal of unused human medications. The specific pathways by which veterinary pharmaceuticals are released to the environment are not as yet clear. USGS currently is investigating these pathways and veterinary pharmaceuticals at animal feeding operations across the US.

What can I do to reduce the amount of pharmaceuticals entering the environment?

Guidance for the best current practice for disposal of unused pharmaceuticals has been released by the Office of the National Drug Control Policy. It includes disposing of most pharmaceuticals in the trash, which is ultimately disposed of in landfills. The guidance identifies how to determine how specific pharmaceuticals should be disposed of.

Are the concentrations of pharmaceuticals in streams downstream of the wastewater treatment plants in question a threat to ecological health?

Few environmental or ecological effects assessments have been conducted for the pharmaceuticals measured in this study. Therefore it is difficult to determine the ecological health implications of the presence of these pharmaceuticals at the levels found in these streams. The concentrations found are higher than anticipated and therefore higher than those considered in previous environmental assessments for other pharmaceuticals.

What is USGS currently doing to assist resource managers and industry in addressing this issue?

USGS is continuing its investigations of pharmaceuticals in the environment, including studies in cooperation with the New York State Department of Environmental Conservation. More information on these studies is available on the Internet at: https://toxics.usgs.gov/.

The following USGS activities have been implemented specifically to further assess pharmaceutical manufacturing facilities as environmental sources:

  1. Continuing to monitor the outflow of several wastewater treatment plants and reservoir sampling points in New York State. This activity will continue as a result of common interests and support from the New York State Dept of Environemntal Conservation.
  2. Analyzing samples for an expanded list of pharmaceuticals and pharmaceutical intermediates.
  3. Collecting data on the presence of pharmaceuticals in additional media (fish, sediment, and biosolids).
  4. Continuing to participate in testing of alternative techniques designed to reduce levels in wastewater treatment plant outlows.
  5. Initiating ecological effects research to determine if there are potential adverse effects on fish associated with the elevated pharmaceutical concentrations observed in these streams.
  6. Offering additional technical assistance to the wastewater treatment plants and pharmaceutical manufacturing facilities with the goal of reducing pharmaceutical concentrations in wastewater effluents.

Is it possible that some of the pharmaceuticals measured in this study were introduced into samples accidentally either during sample collection or laboratory analysis?

Ensuring that the data reported in this paper are representative of environmental conditions is a top priority of this and other USGS studies. An extensive quality assurance program was conducted as part of this study to help ensure the reliability and quality of the data. The personnel collecting these water samples have been extensively trained to collect environmental samples for analyses of chemical compounds at extremely low concentrations. This training ensures that the samples collected were of the highest quality. Field duplicates and field blanks were collected to act as a quality control check on the data. Samples of various types of environmental waters were spiked with known levels of the chemicals and tested. In addition, an extensive laboratory quality assurance program was implemented for this study.


Phillips, P.J., Smith, S.G., Kolpin, D.W., Zaugg, S.D., Buxton, H.T., Furlong, E.T., Esposito, Kathleen, and Stinson, Beverley, 2010, Pharmaceutical formulation facilities as sources of opioids and other pharmaceuticals to wastewater treatment plant effluents: Environmental Science and Technology

Phillips, P.J., Smith, S.G., Kolpin, D.W., Zaugg, S.D., Buxton, H.T., Furlong, E.T., Esposito, Kathleen, and Stinson, Beverley, 2010, Method description, quality assurance, environmental data, and other information for analysis of pharmaceuticals in wastewater-treatment-plant effluents, stream water, and reservoirs, 2004-2009: U.S. Geological Survey Open-File Report 2010-1102, 2010.

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