The pertinence of Sutton's law to exposure science: Lessons from unconventional shale gas drilling.

Sutton's Law urges the medical practitioner to utilize the test that goes directly to the problem. When applied to exposure science, Sutton's Law would argue that the major emphasis should be on techniques that directly measure exposure in or close to the human, animal or ecosystem receptors of concern. Exposure science largely and appropriately violates Sutton's Law by estimating exposure based on information on emissions or measurements obtained at a distance from the receptors of concern. I suggest four criteria to help determine whether Sutton's law should be violated for an innovative technology, and explore these criteria in relation to potential human exposure resulting from unconventional gas drilling (UGD): (1) The technological processes possibly leading to release of the chemical or physical agents of concern are reasonably understood; (2) the agents of concern are known; (3) the source and geographical location of the releases can be reasonably identified; and (4) there is information about the likely temporal pattern of the releases and resulting pollutant levels in relation to the temporal patterns of receptor susceptibility. For UGD, the complexity of the technology including many possible release points at different time periods; the existence of three variable mixtures of chemical and physical agents as well as possible unknown reactants; the demonstrated large variation in releases from site to site; and deficiencies in transparency and regulatory oversight, all suggest that studies of the potential health impact of UGD should follow Sutton's Law. This includes the use of techniques that more directly measure exposure close to or within the receptors of concern, such as biological markers or through community-based citizen science. Understanding the implications of Sutton's Law could help focus scientific and regulatory efforts on effective approaches to evaluate the potential health and ecosystem implications of new and evolving technologies.