9

Research Opportunities: Federal Representatives

This chapter presents a summary of a high-level discussion of environmental health and hydraulic fracturing from the perspective of the U.S. Environmental Protection Agency (EPA) and the research needs and opportunities to ensure that the public’s health is protected. The chapter also includes a summary of perspectives of four federal agency representatives—from the National Institute of Environmental Health Sciences (NIEHS), the U.S. Geological Survey (USGS), the Occupational Safety and Health Administration (OSHA), and the Centers for Disease Control and Prevention (CDC)—on agency research activities. The presentations are followed by a summary of the discussion that occurred between panelists and members of the audience. The dialogue covered a broad range of topics raised over the 2-day workshop.

ENVIRONMENTAL HEALTH AND HYDRAULIC FRACTURING

Bob Perciasepe, M.P.A.
Deputy Administrator, U.S. Environmental Protection Agency

Bob Perciasepe stated that while the EPA plays a broad role in environmental protection and natural resources management, its scope of work goes well beyond wildlife and endangered species to the EPA’s priority in environmental public health. The agency is guided by science and laws to ensure that the agency implements protections to combat air pollution, water pollution, unsafe drinking water, and soil contaminants. The EPA’s work addresses many of the environmental challenges facing society today. In this approach of protecting human health, there will be cobenefits for wildlife and the broader natural resources, according to Mr. Perciasepe.

Many of the challenges facing the United States today are related to developing a sustainable and robust economy. Mr. Perciasepe believes



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9 Research Opportunities: Federal Representatives This chapter presents a summary of a high-level discussion of environmental health and hydraulic fracturing from the perspective of the U.S. Environmental Protection Agency (EPA) and the research needs and opportunities to ensure that the public’s health is protected. The chapter also includes a summary of perspectives of four federal agency representatives—from the National Institute of Environmental Health Sciences (NIEHS), the U.S. Geological Survey (USGS), the Occupat- ional Safety and Health Administration (OSHA), and the Centers for Disease Control and Prevention (CDC)—on agency research activities. The presentations are followed by a summary of the discussion that occurred between panelists and members of the audience. The dialogue covered a broad range of topics raised over the 2-day workshop. ENVIRONMENTAL HEALTH AND HYDRAULIC FRACTURING Bob Perciasepe, M.P.A. Deputy Administrator, U.S. Environmental Protection Agency Bob Perciasepe stated that while the EPA plays a broad role in environmental protection and natural resources management, its scope of work goes well beyond wildlife and endangered species to the EPA’s priority in environmental public health. The agency is guided by science and laws to ensure that the agency implements protections to combat air pollution, water pollution, unsafe drinking water, and soil contaminants. The EPA’s work addresses many of the environmental challenges facing society today. In this approach of protecting human health, there will be cobenefits for wildlife and the broader natural resources, according to Mr. Perciasepe. Many of the challenges facing the United States today are related to developing a sustainable and robust economy. Mr. Perciasepe believes 105

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106 HEALTH IMPACT ASSESSMENT OF SHALE GAS EXTRACTION that addressing these challenges are part of the EPA’s mission, partic- ularly in terms of the debate about whether a strong economy and environmental protection can work together. He stressed that the current U.S. economic conditions or any economic crisis is unrelated to having high environmental standards. The importance of having a clean, sustainable economy has been reinforced by President Obama in his 2012 State of the Union Address when he spoke about an economy built to last—one built on clean, cheaper energy. Mr. Perciasepe emphasized the need for developing new energy sources and how the EPA reviews existing energy resources and also plays a proactive role in identifying new sources such as wind and solar. In other words, the EPA is prioritizing safe and effective ways to maximize the nation’s oil and gas resources. Similar to previous speakers, Mr. Perciasepe reiterated that natural gas will play a positive role in the nation’s near-term energy policy in order to have a steady supply and ensure energy security. However, the EPA has heard the many concerns raised about human health implications of oil and gas development. It is clear that those concerns need to be addressed with care, he said. Natural gas, from a pollution standpoint, releases less carbon dioxide than other forms of energy. While noting this, Mr. Perciasepe cautioned that these resources have to be developed safely and responsibly. Natural gas development has the ability to create jobs and provide fuel for cleaner transportation. In moving toward safe ways to effectively explore and develop U.S. natural gas resources, the EPA has allocated 45 million dollars toward ensuring a coordinated, interagency, research effort. Mr. Perciasepe also discussed the new executive order that is requiring agencies to be more coordinated in looking at all of the issues related to natural gas development, including hydraulic fracturing. The EPA, Department of Energy, and Department of the Interior have signed a memorandum of understanding to coordinate the expenditure of funds on research into all the different aspects of natural gas development. Although Mr. Perciasepe feels that there is a need to take full advantage of these technologies, he also stressed the need to give Americans confidence and ensure that neither their health nor natural resources will be sacrificed in that process. The EPA has completed standards to reduce harmful air emissions and pollution associated with natural gas production. Under the Clean Air Act, new source performance standards are aimed at those emissions at the well head and also in some of the transport and pipeline storage systems. Mr. Perciasepe stated that these standards are important because as the wells are being prepared for natural gas production, they can emit volatile organic compounds (VOCs). VOCs contribute to ozone pro- duction, which results in the development of ozone problems. The wells can also emit chemicals, such as benzene and hexane, depending on the composition of the natural gas, which have potential carcinogenic

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FEDERAL REPRESENTATIVES 107 effects. The EPA is focused not only on reducing VOCs from that process, but also reducing methane emissions, a greenhouse gas. Regulations are based on input from the public, industry, environ- mental organizations, public health organizations, and state regulators. Mr. Perciasepe stated that these newer regulations are good examples of how natural gas resources can be developed while protecting public health and natural resources. The additional costs resulting from these regulations will be offset by the increase in natural gas captured; according to Mr. Perciasepe, an estimated $19 million will be saved annually by implementation of these regulations. Mr. Perciasepe emphasized that safe water is a priority area of concern, including drinking water sources, the amount of water being used in the hydraulic fracturing process, and underground chemical injection control. The EPA has begun a study of the impact of hydraulic fracturing on drinking water resources, both groundwater and surface water. Mr. Perciasepe feels that when it is completed, the study will help move forward some of the scientific uncertainties related to water and hydraulic fracturing. Further, it will equip both the EPA and policy makers with evidence to inform decision making. Mr. Perciasepe noted that the water used in hydraulic fracturing is recycled and reused, but eventually, the water will be disposed in a sewage treatment plant. Current EPA regulations do not allow for hydraulic fracturing fluids to be discharged into surface waters. The EPA is in the process of developing guidelines to regulate what quality level must be achieved before the water can be discharged into other treatment systems. Minimal disruption is the intent, according to Mr. Perciasepe. The EPA is completing guidelines for underground injection control permitting groups in regional offices as well as some of the state agencies that have primacy for the underground injection control program on what practices should be used if any diesel fuel is used in the fracturing fluids. To the extent that these components of a fracturing fluid are not exempted under federal law, Mr. Perciasepe stressed that the EPA wants to ensure that there are proper guidelines in place if and when they use. One common misconception he mentioned is that the EPA is standing in the way of natural gas and oil and natural resource development. Mr. Perciasepe noted that since 2008, natural gas and oil production in the United States has actually increased. Further, crude oil production in 2010 was higher than it was in any year in the previous decade. Production is occurring, but the EPA is committed to minimizing environmental and public health impacts. Mr. Perciasepe reiterated that environmental and public health protection has a solid history to guide the approaches for the future. Forty years ago, air pollution in most cities in the United States was visible; water was visibly polluted, and other environmental hazards were clear. He noted that considerable progress has been made, but the

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108 HEALTH IMPACT ASSESSMENT OF SHALE GAS EXTRACTION public needs to understand that the challenges today are not quite as obvious as some of the challenges from 40 years ago. Today’s challenges include climate change, existing pollutants, and the nation’s aging infrastructure. Mr. Perciasepe is optimistic that the country can address these challenges and move forward and make great progress. He noted that most of the evidence shows that the country can protect the environment along with creating robust economic growth. He used the example that fuel economy standards for automobiles reduce greenhouse gas emission (6 billion metric tons of carbon pollution), other VOCs, and fine-particle pollution. At the same time, the standards improve national security efforts and energy security plans. He noted that the United States could save more than a trillion dollars in gasoline costs as a result of lower gasoline demand from the automobile and light-duty truck sector. He stressed that although it is important to reduce demand on oil and develop alternative fuels, there is no single solution to all of these different mixes of energy issues in the United States. An interconnected, resilient energy system that supports policies that build a sustainable energy economy in the United States will protect the environment and public health. PERSPECTIVES ON AGENCY RESEARCH ACTIVITIES John M. Balbus, M.D., M.P.H. Senior Advisor for Public Health, National Institute of Environmental Health Sciences National Institutes of Health John M. Balbus described the NIEHS as a complex research institute with many programs that can help play a role in determining health implications of hydraulic fracturing. The institute is primarily a biomedical research institute with the majority of the funding activities being dedicated to investigator-initiated proposals. As an institute of the National Institutes of Health (NIH), Dr. Balbus noted that there is limited capacity to initiate new activities. The NIEHS is looking at existing mechanisms of support and ensuring that they provide the right mechanisms to start addressing and answering the kinds of questions raised during this workshop. The NIEHS’s intramural laboratory programs include the National Toxicology Program,1 a freestanding clinical research unit, and extramural funding. Within the extramural program, Time Sensitive Grants, is a special small-grant-making program, Mechanism for Time- 1 See http://ntp-server.niehs.nih.gov (accessed May 30, 2013).

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FEDERAL REPRESENTATIVES 109 Sensitive Research Opportunities in Environmental Health Sciences,2 explicitly set up to address emerging issues and collect data in a relatively short time frame. A second existing mechanism is the Research to Action program,3 which translates basic science into public health action. Dr. Balbus described recent funding announcements regarding cumulative stressors and community exposures in addition to environmental exposures. The NIEHS has a number of environmental health science centers throughout the country that focus on topics such as breast cancer and children’s environmental health. Each of the centers is required to have a community-oriented core consisting of community outreach, educational activities, and partnerships with community groups, and local and state decision makers. Some of the environmental health centers are located in areas that are being affected by hydraulic fracturing, according to Dr. Balbus. The directors are starting discussions and webinars and developing proposals to address some of the issues raised regarding the safety of the process. Another avenue for involvement according to Dr. Balbus is the Workers’ Training Program,4 which was created to help train hazardous waste workers and emergency response workers on environmental health issues. He described it as a very robust network with partnerships between academic groups, educators, and labor unions. The network is a resource during emergency response periods. The last program that Dr. Balbus detailed is the National Toxicology Program, a joint program between the Food and Drug Administration, the National Institute for Occupational Safety and Health (NIOSH), and the agencies of NIH. It exists to serve both the agencies and the public in evaluating the toxicity of substances, mixtures, and exposures of a whole variety of kinds from naturally occurring to synthetic materials. One of the components the National Toxicology Program is active investigation of the Tox21 high-throughput screening program—a program not set up to do in-depth toxicological evaluation, according to Dr. Balbus, but to screen large numbers of substances at once. The National Toxicology Program accepts public and self-generated nominations of substances for study. The group is reviewing hydraulic fracturing chemicals and seeking to determine the most appropriate mixtures. One large challenge that Dr. Balbus highlighted is the lack of information about what the public is being exposed to and what are the mixtures of greatest concern. 2 See http://grants.nih.gov/grants/guide/pa-files/PAR-13-136.html (accessed May 30, 2013). 3 See http://www.niehs.nih.gov/research/supported/dert/sphb/programs/peph/ prog/rta (accessed May 30, 2013). 4 See http://www.niehs.nih.gov/research/supported/dert/wet/index.cfm (accessed May 30, 2013).

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110 HEALTH IMPACT ASSESSMENT OF SHALE GAS EXTRACTION In conclusion, Dr. Balbus noted a number of epidemiologic needs, including  baseline health status of affected communities,  site characterization and identification of highest-priority sub- stances and mixtures to undergo toxicologic testing, and  coordination between levels of government and agencies to respond to communities, obtain samples and health data, and communicate results. Suzette M. Kimball, Ph.D. Associate Director for Geology, U.S. Geological Survey U.S. Department of the Interior Suzette M. Kimball provided background to the audience on the USGS. The agency does not have regulatory or resource management responsibilities. Its mission is to produce objective, unbiased science and thus is uniquely positioned to support the President’s executive order that emphasizes the need for coordinated science and coordinated activities to support the decisions surrounding environmental health issues potentially related to shale gas extraction. The USGS’s key role includes supporting safe and responsible development of both conventional and uncon- ventional domestic natural gas resources and in understanding the global distribution, global extent, and global access to energy resources. Dr. Kimball noted that the agency’s work has for many years looked at energy resource assessments, hazards associated with seismic activity, energy development-associated risks, hydrogeologic investigations, and most recently, environmental health. She proposed that the need is paramount for the first three in order to understand the geologic framework and the hydrologic and geologic conditions that are associated with the extraction of these resources in order to be able to make informed decisions about environmental health. Dr. Kimball expanded by saying that for all research areas in hydraulic fracturing, interagency collaborations will be important. This includes federal, state, and local agencies collaborating with non- governmental organizations and industry. The memo of understanding recently signed by the USGS, the Department of Energy, and the EPA will be able to better align federal resources so that the agencies bring all of the resources that the federal government has to bear on understanding the issues of concern. Dr. Kimball described a number of science priorities for the USGS, including  resource assessments for both conventional and unconventional resources and the related environmental impacts (both ecological and human components);

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FEDERAL REPRESENTATIVES 111  water use and impact on supplies for humans and ecosystems;  Impacts of produced and flowback waters on aquatic life in receiving water bodies;  geochemistry and toxicity of fluids from shale gas wells;  habitat destruction and forest fragmentation;  assessments of the geographic footprint of extraction and related activities; and  induced seismicity. The agency, according to Dr. Kimball, is focusing its interdisciplinary science to address the growing complex questions around potential environmental health impacts in several key areas, such as resource extraction, production storage and transmission activities, and life-cycle assessments of related issues including waste management activities. To address these large-scale activities, several projects have been started. Dr. Kimball described the projects as a series of resource assessments both nationally and globally on tight gas, shale gas, tight oil, and coal bed methane. In addition to continuing its nationwide stream gauging and water availability studies, the USGS is completing water quality sampling and monitoring, targeting studies, and tailoring the existing network so that environmental health issues can be addressed. As mentioned earlier, the USGS is planning to sample and analyze flowback water for natural radiation. The agency scientists are also developing laboratory methods to measure chemicals in a wide range of fluids, including the fluids produced in hydraulic fracturing. Other research activities include using groundwater flow modeling to predict the fate of injected fluids, documenting landscape changes using specific satellite imagery to understand implications for wildlife, and induced seismicity as a result of wastewater and fluid injection subsequent to a fracturing process. Dr. Kimball concluded by stating that all of those are efforts that will provide some of the baseline studies to inform environmental health decision making. David M. Michaels, Ph.D., M.P.H. Assistant Secretary of Labor, Occupational Safety and Health Administration U.S. Department of Labor David M. Michaels commenced his presentation by noting that workers are an integral part of the safe use and the safe production of unconventional resources and at the same time, they are vulnerable to potential adverse events associated with hydraulic fracturing. Oil and gas drilling in general is one of the most hazardous occupations in the United States. Over the years the fatality rate has been

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112 HEALTH IMPACT ASSESSMENT OF SHALE GAS EXTRACTION about seven times higher than the rate for all U.S. workers (CDC, 2012) and that is before the proliferation of hydraulic fracturing. Shale gas extraction has many of the same hazards associated with this industry, but also introduces new hazards previously unseen to this extent in the petroleum industry. At times when new technologies are put into place, new hazards are seen; although the hazards associated with shale gas extraction are not new—silica exposure, diesel exposure, falls, and motor vehicle incidents—it is the constellation of these hazards that is unique. Motor vehicles, for example, are the major cause of fatalities involved in upstream oil and gas production. The task of bringing in millions of gallons of water and hundreds of thousands of tons of sand to shale gas extraction sites requires large numbers of vehicles to travel off- road and that has resulted in increased fatalities. There are multiple tools to address workplace hazards. OSHA works closely with employers and industry to reduce workplace hazards. There are a number of large employers and large companies that are involved in shale gas extraction who are very committed to safety. Many of these companies extend safety standards down to all their contractors. A number of oil and gas companies formed the Service, Transmission, Exploration, and Production Safety Network (STEPS).5 This network promotes safety, health, and environmental improvement in the exploration and production of oil and gas. Network meetings emphasize educating companies and contractors about the safety issues. However, new people enter this industry all the time who may not necessarily have the skills or the commitment to worker safety, and so, education should be a continuous effort. Another approach that OSHA uses is to work jointly with other agencies that are involved earlier in the shale gas extraction process, for example, working with agencies responsible for permitting. It is critical to be involved early before drilling occurs and during the drilling process. Once the drilling is complete and the product is being extracted, the risks, injuries, and fatalities are very low. Dr. Michaels further noted that there is a mosaic of federal and state agencies that have different regulatory responsibilities with some overlap, but some gaps. The usual model of oversight typically results in one visit in the course of a long period of production and that often does not allow enough time to see the hazards. Working jointly with other agencies helps expand the opportunities to identify and address potential hazards. 5 The Network changed its name from the South Texas Exploration and Production Safety Network (OSHA, 2007).

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FEDERAL REPRESENTATIVES 113 Christopher J. Portier, Ph.D. Director, National Center for Environmental Health and Agency for Toxic Substances and Disease Registry Centers for Disease Control and Prevention Christopher J. Portier stated that CDC is America’s public health agency for research and response to ongoing and emerging public health issues. The Agency for Toxic Substances and Disease Registry (ATSDR) and the National Center for Environmental Health (NCEH) have a number of ways to contribute to the understanding of the health implications of this new technology. One way is to study the potential toxicity of the compounds used in shale gas extraction. ATSDR maintains toxic profiles that are regarded internationally as some of the best reviews of the toxicological literature, and staff at ATSDR and NCEH are working with the NIEHS and with the EPA to evaluate these com- pounds. A second way is to directly evaluate human effects from shale gas extraction. ATSDR and NCEH have human health study groups dedicated to understanding health impacts from environmental exposures; they have been asked to identify what information is needed to clarify concerns and reduce any public health effects from shale gas extraction. A third way to contribute to the understanding of health effects of shale gas extraction was initiated by Congress. Congress specifically asked the Environmental Health Tracking Network at NCEH to develop baseline community health data that will eventually allow communities to monitor the impact of current and future drilling sites on the health of individuals living nearby. NCEH currently has a program on the safety of unregulated water. This program may need to be extended and linked with environmental public health tracking to improve surveillance in areas where shale gas extraction is prevalent. Finally, the medical education group at NCEH can develop guidance for health care professionals to enhance their understanding of the effects of some of the hazards seen with shale oil extraction, such as noise and stress, on overall health status. In the quest to protect people and save lives, Dr. Portier said, it is clear that we should be working closely with our colleagues in industry to advance public health through identifying ways to help improve shale gas extraction practices. The panel was asked what makes shale gas extraction a unique concern. There are several characteristics of shale gas extraction that have raised questions among health professionals. The chemical constituents are not well characterized, and toxicity data on many of them are limited. A number of questions exist about the mobilization of naturally occurring substances such as methane and heavy metals. The good news, he said, is that many of these issues do have solutions and can be addressed through scientific study. There are opportunities where past experience can be used to reduce concerns almost immediately. The physical hazards

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114 HEALTH IMPACT ASSESSMENT OF SHALE GAS EXTRACTION associated with drilling and the effects of noise and air pollution at drilling operations are not new to shale gas extraction, and the industry has developed ways to limit impacts from these hazards. Best practices, if applied across the board, will have an immediate impact, for example, in the areas of waste handling, treatment, and long-term storage. Dr. Portier concluded that the way forward is for all who are interested in environmental health—local, state, tribal, and federal government agencies, industry, national news media, not-for-profit organizations, and certainly the affected communities—to work together. DISCUSSION During the discussion with the speakers, the panel members responded to a number of questions about the public health response, the monitoring of environmental exposures, and the local public health needs. It was noted by one member of the audience that the United States was not the only country with shale gas and asked if the United States is aware of other countries’ activities in this area. Dr. Kimball noted that the European Union is interested in the topic as are France, Great Britain, Russia, and the Ukraine. She noted that there has not been an assessment of the global reserves of shale gas but the geographic survey directors globally are meeting to begin to understand those reserves. During the discussion, it was noted that different agencies have responsibility for different aspects of the hydraulic fracturing process and that front-line public health officials may not know which agency to call. Dr. Portier noted that NCEH’s health education unit is putting together materials that will be shared with the states. However, he noted that NCEH is still in the information-gathering phase and will need to collect additional information before it can provide leadership and materials to guide this effort. Dr. Balbus noted that the NIEHS’s environmental health science centers have a network—Partnerships for Environmental Public Health—of scientists, community members, educators, health care providers, public health officials, and policy makers who share the goal of increasing the impact of environmental public health research at the local, regional, and national levels. This network communicates between the NIEHS and stakeholders in the communities, including community groups and state and local public health officials. As the centers in the affected areas begin to develop education and training activities, this information will be a resource that will be available nationwide on the Internet. Another audience member commented that the health response has been fragmented across the federal, state, and local governments. Dr. Michaels noted that the original interagency working group did not include OSHA, but this has changed. He said that there was a commitment

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FEDERAL REPRESENTATIVES 115 on behalf of all the agencies to work more cooperatively and creatively to address these very tough issues. Dr. Goldman noted that it comes back to a recurring theme of public health needing to be more involved. At the same time, she noted that health agencies are often reluctant to accept responsibility for something that they feel should be the responsibility of the EPA or OSHA. Dr. Goldman further stated that the scientific community that is concerned about health and medicine needs to ensure that represent- atives in state health departments and the Department of Health and Human Services understand that environmental health is about health. Health goes beyond health care payments, health care reform—health includes the environment, but it is a dimension of health that is often overlooked. Another audience member noted that an unprecedented number of workforce reductions have occurred at the state and local levels which makes responding to challenges such as hydraulic fracturing difficult, if not impossible. The audience member asked how can the public health infrastructure of the country be maintained or rebuilt. Dr. Portier noted that the CDC is committed to trying to maintain and hold together the strength of the public health force of the United States. In the past few years, state and local governments have lost approximately 700,000 jobs, and approximately 200,000 of those are in health and environmental areas. Dr. Balbus added that environmental health has not been as effective as other entities in making the economic case for rebuilding the public health infrastructure. He suggested that there is a research and science need to build environmental health economics in order to make the economic case for an investment in the environmental health infrastructure. Another audience member noted that currently many of the agencies and organizations that are involved in addressing environmental health concerns are in a reactive mode. The audience member questioned whether there were opportunities for federal agencies to develop voluntary guidelines for states on issues such as monitoring wells prior to their installation. Dr. Portier noted that the CDC would be willing to work with other agencies, such as the EPA, to develop exemplary or model guidelines for states to consider. An audience member raised the concern about the potential health effects of radon that are associated with the natural gas that is extracted and that will eventually go to the consumer. As the gas travels to the consumer, it will be plating out in the distribution lines with polonium- 210 and lead-210, both of which are solids that make those pipes radioactive, and maintenance workers will be exposed during the process. Further, he noted, radioactivity levels in the produced gas in these various fields has not been examined in some time. There were EPA studies in the 1970s of radon in gases from shale deposits across the country and USGS data from the Marcellus Shale in the 1980s, but more recent studies are lacking. The audience member asked the panel if

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116 HEALTH IMPACT ASSESSMENT OF SHALE GAS EXTRACTION agencies were concerned about radon in the end product. Dr. Kimball responded that the USGS is undertaking a set of studies of naturally occurring radionuclide elements. It is known that within the Piedmont areas of the East Coast, radon is an issue, but it is an issue for a number of reasons, not just shale gas extraction. The state geological surveys are in the process of completing state geologic maps. As they begin to look beyond surface geology, there is an opportunity to look at this issue. Those studies are under way. Finally, the panel was asked to comment on the testing of acute, short-term exposures versus low-level chronic exposures, for example, the low-level chronic exposures of farmers who leased out their land for hydraulic fracturing or homeowners who are living 100 feet from a compressor station and live with these emissions daily. The audience member noted that there has been remarkably little air and water testing in the U.S. gas fields to date, and the available testing efforts have shown exposures at “safe” levels, which is disheartening for people exper- iencing a multiplicity of health symptoms at these levels. The audience member questioned whether these standards needed to be changed. Dr. Portier responded by explaining that NCEH’s toxicology profiles are guidance values for people to use in deciding whether to act in a particular situation; but they are not standards. There are three different guidance values for each level of exposure: acute (exposures of less than a few hours to 1 week), medium (up to 1 year), and chronic exposures (greater than 1 year). For the guidance, he noted that what is allowed for acute exposure is greater than what is allowed for medium-term or chronic exposure. Dr. Portier noted that many of the decisions that are made are based upon the acute exposure value. REFERENCES CDC (Centers for Disease Control and Prevention). 2012. Oil and gas extraction. Occupational safety and health risks: Fatalities. http://www.cdc. gov/niosh/programs/oilgas/risks.html (accessed May 30, 2013). OSHA (Occupational Safety and Health Administration). 2007. Annual Alliance Report: South Texas Exploration and Production Safety Network (STEPS). http://www.osha.gov/dcsp/alliances/regional/reg6/steps_annualreport2007- 2008.html (accessed May 30, 2013).