PUBLIC HEALTH IMPLICATIONS OF HYDRAULIC FRACTURING

There are three major chemical threats to human health associated with hydraulic fracturing, otherwise known as “fracking”. These are contamination of ground water with fracking chemicals, release of volatile organic compounds into the air resulting from the inhalation of dangerous substances among workers and nearby residents, and release of radioactivity into the environment coming from the radium that is in the flowback that returns to the surface. While fracking sites are much deeper than ground water, contamination of air or ground water with fracking-related chemicals can occur if there is a break in the concrete linings of the well, or if there are surface releases of chemicals that lead to groundwater contamination. The gas released, in addition to methane, also may contain known human carcinogenic substances, such as benzene and formaldehyde, as well as hydrogen disulfide or many other volatile organics, all of whom are known to cause respiratory and nervous system disorders. Radium and radon also represent naturally occuring carcinogens.

As a result of this complex assortment of anthropogenic and natural chemical constituents, pathways for exposure, and mechanisms of action, there is considerable uncertainty in the potential toxic impact and the associated public health implications of shale gas development. Accurately characterizing the various potentially toxic components and disseminating this knowledge into other fields of expertise (toxciology, occupational medicine, and public health) are critical components of the risk assessment paradigm. I will discuss how these factors are integrated into informed public health decision making.