Health of Cattle and Wildlife Downwind from Gas Faeilities: The Western Canada Study

摘要

Conflict over land use between natural gas development and cattle ranching became acute in western Canada until in 2000 the Western Canada Study was organized to investigate allegations of health effects. There were two important goals: 1) to determine if emissions downwind from oil and gas facilities influence the reproduction and health of cattle and wildlife in western Canada and 2) to provide new and economically useful information for cow-calf producers on factors affecting herd productivity and herd health. An arm's-length management agency was set up to support and oversee the study, with multiple stakeholders involved. The principal investigator for the Study was Dr. Cheryl Waldner, veterinary epidemiologist at the University of Saskatchewan. The author chaired the Scientific Advisory Pane, which took an active role in study design and provided oversight. An arm of the Study devoted to human health was terminated before it began, ostensibly as a budgetary recission but probably for political reasons.A tandem wildlife study was implemented using European starlings as an indicator species. The overall pattern of findings demonstrated no adverse effect of downwind exposure on animal health, although the Study found some associations that suggested possible effects at levels of SO2 much lower than expected . Air quality in field locations compared favorably with other rural and with urban centers. Important design features of this Study included the innovative management structure, a secondary goal of improving herd management, a hypothesis-driven study protocol, and the unusually active role of science advisors. Emphasis in this presentation is on the study design, exposure assessment methodology and project management. The innovations and practices of this Study, and in particular the management organization of WISSA, could be a useful model for conducting studies in the context of similarly contentious issues, such as "tight" (shale) oil and gas recovery using fracking.