Risk and Responsibility: Farming, Food and Unconventional Gas Drilling by Michelle Bamberger and Robert E. Oswald, November 12, 2012, Independent Science News
Extraction of hydrocarbon gas from tight shale formations using horizontal drilling and hydraulic fracturing has been advertised as a path toward energy independence for the United States and is being promoted worldwide. This is tempered by environmental and societal concerns that have led to banning the practice in some countries (e.g., France), at least one state in the U.S. (Vermont), and numerous towns and cities in the United States. In the United States, the process itself is largely regulated at the state level, with exemptions from federal laws regulating air, drinking water and hazardous waste disposal. Regulation at the state level varies considerably among states with significant shale deposits, as does the level of enforcement of regulations. The argument often given to suggest that the process is safe cites the fact that in the sixty years since the first gas well was hydraulically fractured, the industry has not found proof it finds acceptable that drinking water has been contaminated. This assertion is not universally accepted because of at least two factors.
First, it is based on a narrow definition of hydraulic fracturing, that is, solely the process of stimulation of the well; whereas, the public and many in academia are more concerned with the entire life-cycle of the drilling and extraction process with many possible routes of environmental contamination. The second issue is the burden of proof. Is it the public or the government that bears the burden of proving that environmental harm has occurred or should the industry be required to provide scientifically acceptable proof of the safety of the process? In this paper, we will discuss regulation briefly followed by a more detailed discussion of health effects of shale gas extraction, and possible impacts on food safety.
In a recent issue of Independent Science News (1), William Sanjour carefully reviewed the inherent problems of regulatory agencies. While his view was informed by thirty years of experience working for the US Environmental Protection Agency (EPA), his comments raise important concerns for state regulatory agencies as well. One important point that he raised was: “Agencies which enforce regulations should not write the regulations.” This was recognized by the US Department of the Interior after the Deepwater Horizon blowout when the Minerals Management Service, with allegedly strong connections to industry, was divided into permitting (Bureau of Ocean Energy Management) and regulatory (Bureau of Safety and Environmental Enforcement) branches.
Taking the example of New York State, the Department of Environmental Conservation (DEC), which has written the proposed hydraulic fracturing regulations, will be responsible both for issuing permits for the wells and enforcing the regulations. The two most important concerns are that the NYS DEC has been chronically understaffed, particularly with regard to permitting and regulating gas wells. Expansion of the program to high volume shale gas wells will only exacerbate the problem. Secondly, the agency has the dual missions of extracting minerals efficiently and protecting the environment. While an increase in state or federal bureaucracy will never be politically popular, there is an inherent conflict of interest between these two missions and it makes little sense to charge a small staff with this dual mandate. Careful oversight of this global industry, which is in the best interest of the public and the industry, can only be done if regulatory agencies are truly independent and have sufficient staffing to detect problems and provide effective enforcement.
Our interest has been on the use of animals as sentinels of human health in areas experiencing extensive shale gas and oil extraction. Animals tend to have greater exposure to environmental threats than humans because they typically have greater exposure to air, soil and groundwater and have more frequent reproductive cycles and shorter generation times. For example, animal owners can often afford to purchase drinking water for their own use, but purchasing drinking water for a herd of cattle can be beyond the means of some farmers. Thus, the cattle have a much greater exposure to potentially contaminated water than the farmer.
The question is whether or not any of the processes associated with shale gas and oil extraction have led to adverse health consequences in animals or humans. We have published an analysis of case reports from 24 families with plausible exposures to toxicants associated with one or more phases of the drilling process (2). One approach to obtaining more definitive evidence might be to determine if specific chemical residues can be found in the environment following hydraulic fracturing operations that were not present before those operations began, identify a route of exposure, and then attempt to determine if the concentrations present in the exposure pathway could have caused health problems. On the surface, this is a logical approach that has been used for many years by environmental toxicologists.
But the problem faced in analyzing the health effects of shale gas extraction is not as simple as finding hexavalent chromium in the drinking water. It is an extremely complex problem with the potential of exposures from multiple chemical entities (known and unknown), multiple routes of exposure, and unknown interactions between chemicals. Furthermore, recent evidence suggests that the effects of chemicals at high doses cannot accurately predict effects at lower does (nonmonotonic dose response curves; 3). This is particularly true for endocrine disrupting chemicals that have been reported to be components of hydraulic fracturing fluid (4). For these reasons, the maximum contaminant levels (MCLs) of specific compounds that are used to determine the safety of drinking water are questionable. The problem is compounded by inadequate or nonexistent predrilling testing of air and water in many cases and by nondisclosure agreements tied to victim compensation that remove the details of specific cases from further study.
Documenting individual cases will always be limited to individuals that are willing or able to talk to investigators but in our research we have run into significant unnecessary obstacles. For example in one small area of Pennsylvania, residents were surveyed as to whether drilling had impacted the perceived quality of their water supply (the water was supplied by wells between 40 and 200 feet deep). As of this writing, 50 of 132 families indicated that they noted changes in water quality (Prof. John Stolz, Duquesne University, personal communication) but only a small fraction were willing to provide further documentation. In other cases, residents having presumed issues with water quality have signed nondisclosure agreements in exchange for compensation from industry. This is a worrying distortion of an important business practice. If we take the example used above of a pharmaceutical company, it would be considered unethical to compensate individuals suffering from an unknown side effect of a drug and then require them to sign nondisclosure agreements in an attempt to keep the drug on the market. The use of the nondisclosure agreement in issues relating to public and environmental health should be illegal (6).
The impacts of shale gas drilling on food safety have not been carefully studied and little is known. Again working from case studies, we have reported (2) that cattle exposed to wastewater from drilling operations have been taken to slaughter without further testing. In many instances, those that have died following exposures to drilling operations have been taken to rendering plants, where their flesh has been processed into feed for other animals (e.g., chickens, pigs, fish). These are concerns without definitive proof. No routine testing is done before allowing the products derived from animals exposed to environmental contaminants to enter our food supply, nor is there adequate information on appropriate hold times (time between exposure and slaughter) for production animals with known exposures to environmental toxicants. Equally, nothing is known about impacts on vegetable and fruit crops. We have visited farms with crops growing within tens of feet from produced water tanks (i.e., tanks containing fluids that return from the well along with the gas) and well-heads, and fields of corn and squash near impoundment ponds that contain wastewater at different stages of the drilling process. The extent to which this is a concern is not known, but deserves careful study.
The unconventional gas-drilling boom has swept across the globe in recent years without evidence that environmental and public health can be protected. In the United States, the industry enjoys extensive subsidies, which include, among many others, exemptions from federal laws regulating clean air, clean water, and the disposal of toxic substances. A patchwork of state regulations allow secrecy rather than disclosure of substances used in all steps of the process, and nondisclosure agreements have been used to block access to information on specific cases that could provide meaningful public health information. Without complete transparency (disclosure of all chemicals used and outlawing nondisclosure agreements in cases involving public health) and complete testing, science cannot proceed unimpeded. Without careful science demonstrating, not the absence of proof of harm, but rather the clear absence of harm to public health, neither state nor federal regulations can assure that the food supply and the health of individuals living near gas drilling and processing operations will be protected. Until we can protect public health with greater certainty, unconventional shale gas extraction should be severely limited or banned, using the subsidies currently provided to support this industry to instead develop and deploy renewable forms of energy. [Emphasis added]