Conversations on the environmental and public health impacts of shale gas development enabled by hydraulic fracturing continue to play out in the media, in policy discussions, and among the general public. But what does the science actually say? While research continues to lag behind the rapid scaling of unconventional forms of oil and gas development, there has been a surge of peer-reviewed scientific papers published in recent years (Figure 1). In fact, of all the available literature on the impacts of shale gas development, over 75% has been published since January 1, 2013. What this tells us is that the scientific community is only now beginning to understand the environmental and public health implications. Numerous hazards and risks have been identified, but many data gaps remain. While there is now a far more substantive body of science than there was several years ago, there is still a notable dearth of quantitative epidemiology that assesses associations between risk factors and human health outcomes among populations.
In this analysis we provide an overview of current scientific knowledge regarding these potential impacts. We include only published peer-reviewed literature available on the subject. Specifically, we analyze studies relevant to near-term and long-term environmental public health among communities in proximity to shale gas development.
As shale gas activities continue to expand, states and countries are in a unique position to learn from experiences and scientific assessment in areas where development is already underway, including parts of Pennsylvania, Texas, and Colorado. While energy policy requires more than empirical data, legislative and regulatory bodies should account for the emerging body of science on the environmental and public health implications of shale gas development. This analysis is an attempt to summarize this emerging body of science from the available peer-reviewed literature.
There are many limitations to our analysis and it provides just a snapshot of the empirical knowledge on the public health hazards, risks, and impacts associated with shale gas development. For a more nuanced discussion please refer to our review article (Shonkoff et al. 2014) published in Environmental Health Perspectives (http://ehp.niehs.nih.gov/wp-content/uploads/122/8/ehp.1307866.pdf). Furthermore, as a working paper, this document is preliminary and has not yet been subjected to external peer review. Nonetheless, it provides readers with a general sense of the direction in which the existing body of scientific literature points in terms of identified and potential environmental and public health impacts.