This section presents information on (1) the ways in which pharmaceuticals may enter drinking water, (2) pharmaceuticals in drinking water as a contaminant of emerging concern, (3) the degree to which relevant environmental statutes regulate pharmaceuticals, and (4) the establishment of the PiE workgroup. Scientists have identified numerous pathways by which pharmaceuticals may enter the environment and ultimately drinking water supplies. According to USGS scientists, the main source of human pharmaceuticals in the environment is likely treated wastewater from households, industry, and commercial facilities. Biosolids from wastewater treatment plants applied to land as fertilizer may also be a source of human pharmaceuticals in the environment. Septic systems may be a source of human pharmaceuticals in ground water. A potential source of veterinary pharmaceuticals is agricultural facilities where large numbers of food-producing animals (such as chickens, cattle, and swine) are treated with pharmaceuticals. The pharmaceuticals enter the environment either directly from waste storage structures as a result of accidents or weather conditions, or through the application of manure and liquid waste to croplands. Figure 1 illustrates the different pathways by which pharmaceuticals may enter drinking water supplies. EPA considers pharmaceuticals in drinking water to be a contaminant of emerging concern (also called emerging contaminants). The term is not defined in regulation, and EPA does not maintain a list of contaminants that are considered contaminants of emerging concern. In this report, the term refers to a wide range of contaminants for which the risk to human health and the environment associated with their presence, frequency of occurrence, or source may not be known. In some cases, the release of contaminants of emerging concern into the environment has likely occurred for a long time but may not have been recognized until new detection methods were developed. In other cases, the synthesis of new chemicals or changes in the use and disposal of existing chemicals can create new sources of contaminants of emerging concern. Other contaminants of emerging concern can include personal care products (e.g., sunscreen, antibacterial soap, synthetic musks); chemicals used in industry (e.g., flame retardants, stain resistant coatings); and chemicals used in agriculture (e.g., pesticides that may act as endocrine disrupting chemicals (EDC)). Most pharmaceuticals are not currently regulated under EPA programs implementing key environmental laws. SDWA, the Resource Conservation and Recovery Act of 1976 (RCRA) and the Clean Water Act provide EPA with authority to regulate pharmaceuticals meeting certain criteria in drinking water, waste, and wastewater discharges. Under SDWA, EPA is authorized to regulate contaminants, including pharmaceuticals, meeting certain criteria in public drinking water systems. In 1996, Congress amended SDWA to require EPA to select for consideration those unregulated contaminants that present the greatest public health concern, evaluate their occurrence and the potential health risks associated with them, and decide whether a regulation is needed for at least five contaminants every 5 years. This regulatory determination process includes EPA’s publication in the Federal Register of a preliminary decision on whether the agency will propose a drinking water regulation for each contaminant evaluated—called a preliminary regulatory determination—and provides for a public comment period, followed by a final decision, or regulatory determination, also published in the Federal Register. The 1996 amendments also require EPA to identify and publish a list every 5 years of unregulated contaminants for drinking water that may require regulation—called the Contaminant Candidate List. The Administrator must decide whether to regulate at least five of the contaminants on the candidate list every 5 years. These decisions are called regulatory determinations. SDWA specifies that EPA is to regulate a contaminant if the Administrator determines that the contaminant may have an adverse effect on the health of persons; the contaminant is known to occur or there is a substantial likelihood that the contaminant will occur in public water systems with a frequency and at levels of public health concern; and in the sole judgment of the Administrator, regulation of such contaminant presents a meaningful opportunity for health risk reduction for persons served by public water systems. Since 1996, EPA has completed two regulatory determination cycles—in 2003 and 2008. During this time, EPA conducted 20 regulatory determinations and found that none met the criteria requiring regulation. In 2011, EPA made an out-of-cycle regulatory determination, concluding that perchlorate, an ingredient in rocket fuel and other products that can interfere with the normal functioning of the thyroid gland, met the criteria requiring regulation. EPA has made no regulatory determinations for pharmaceuticals. EPA published the third candidate list in October 2009 but has not yet made any regulatory determinations or completed the third regulatory determination cycle. To determine which contaminants to include on the third candidate list, EPA developed a multistep process, based on available data, to characterize occurrence and adverse health risks a contaminant may pose to consumers of public water systems. Starting with a list of almost 26,000 unique chemicals, EPA identified a universe of about 6,000 potential drinking water contaminants for consideration based on the availability of occurrence and health effects data. Of these, 287 were pharmaceuticals. Then, using the available data, EPA employed successively more detailed evaluations—as well as expert opinions and comments from the public—to identify the 116 contaminants that it included on the third candidate list—12 of these contaminants are pharmaceuticals. Table 1 identifies the 12 pharmaceuticals. In a May 2011 report, we identified systemic limitations in EPA’s implementation of the 1996 amendments’ requirements for determining whether additional contaminants in public drinking water warrant regulation and made 17 recommendations to EPA for implementing the requirements in a way that better assures the public of safe drinking water. Among other things, we recommended that EPA (1) develop criteria and a process for identifying those contaminants on its candidate list that present the greatest public health concern and (2) develop a coordinated process for obtaining both the occurrence and health effects data that may be needed for the agency to make informed regulatory determinations on these priority contaminants. EPA did not agree to adopt these recommendations and generally took the position that no further steps are needed. RCRA established federal requirements and EPA regulatory authority for “cradle-to-grave” management of hazardous wastes, as well as a program for state oversight of nonhazardous solid waste with federal minimum regulations for landfills. RCRA and its implementing regulations establish several means by which waste may be deemed hazardous, including specifically being listed by EPA as a hazardous waste or by exhibiting one of the following four characteristics: toxicity, ignitability, corrosivity, or reactivity. According to EPA’s August 2010 draft guidance and a proposed rule concerning management of hazardous pharmaceutical wastes in the Federal Register, more than 30 active pharmaceutical ingredients are considered listed hazardous wastes under RCRA. In addition, other pharmaceuticals may be considered to be hazardous waste when disposed if they have certain characteristics (e.g., they are likely to leach concentrations of any 1 of 40 different toxic chemicals in amounts above the specified regulatory levels). Examples of these chemicals that have pharmaceutical uses include: arsenic, barium, cadmium, and chloroform. EPA has estimated that about 5 percent of all pharmaceutical waste is hazardous waste. The disposal of pharmaceuticals meeting the RCRA hazardous definition is generally subject to RCRA requirements, such as reporting, using a manifest, and disposing of the waste in approved ways, such as through hazardous waste incineration; however, household trash is exempted. Noting that implementing existing regulations may be difficult for healthcare facilities such as hospitals and nursing homes and that the streamlined requirements would help avoid mismanagement, in 2008 EPA proposed to add hazardous waste pharmaceuticals to the Universal Waste Rule, which simplifies RCRA requirements for certain hazardous wastes. Under the proposed rule, manifests would not be required and other requirements may be simplified. EPA estimated the rule could affect over 600,000 entities. According to EPA’s Web site on the proposed rule, stakeholders commenting on the proposal expressed concerns that including hazardous pharmaceutical wastes under the Universal Waste Rule would eliminate some requirements, such as notification and use of a manifest, that currently apply to such wastes. EPA officials also told us the agency has begun considering additional regulatory options to address these and other issues but that EPA has no projected date for issuing a final rule. The Clean Water Act is the primary federal law concerning pollution of the nation’s waters. Under the act, EPA is required to establish and revise national water quality criteria that accurately reflect the latest scientific knowledge about the effects of pollutants on aquatic life and human health. These criteria represent maximum concentrations that would not cause an unacceptable effect on aquatic life and represent the levels at which specific chemicals are not likely to adversely affect human health. Criteria are elements of state water quality standards, expressed as constituent concentrations, levels, or narrative statements, representing a quality of water that supports a particular use. When criteria are met, water quality will generally protect the designated use. States, or in some instances EPA, use these criteria to adopt and revise water quality standards for designated uses—such as drinking, swimming, or fishing— for water bodies. States may use EPA’s national criteria, modify them to site-specific criteria, or adopt other scientifically defensible criteria. States are required, as part of 3-year reviews, to adopt water quality standards for each of the toxic pollutants for which EPA has promulgated water quality criteria. Water quality standards play a critical role in the act’s framework, potentially affecting effluent limitations dictated by permits and requirements for state reporting and pollution control planning. Regarding permits, EPA and delegated states administer the Clean Water Act’s National Pollutant Discharge Elimination System program, which limits the types and amounts of pollutants that industrial and municipal wastewater treatment facilities may discharge into the nation’s surface waters. Facilities such as municipal wastewater treatment plants and pharmaceutical plants require a permit if they discharge into surface waters. Certain agricultural facilities—known as concentrated animal feeding operations—also need a permit, but other agricultural operations do not.