The Horse as a Sentinel for Human Reproductive and Neurodevelopmental Disorders Associated with Environmental Chemical Exposures

Principal Investigator: Dorothy Ainsworth

Department of Clinical Sciences
Sponsor: NIH-National Institute of Environmental Health Sciences (NIEHS)
Grant Number: 5R21ES026398-02
Title: The Horse as a Sentinel for Human Reproductive and Neurodevelopmental Disorders Associated with Environmental Chemical Exposures
Project Amount: $210,952
Project Period: January 2017 to December 2017

DESCRIPTION (provided by applicant): 

The rapid rate of unconventional natural gas development (UNGD) development is outpacing our understanding of its health and environmental impacts. Individuals and livestock residing in close proximity to UNGD operations experience disorders involving the skin, upper respiratory tract, the musculoskeletal, gastrointestinal, reproductive and central nervous systems. Studies report a positive association between maternal residential proximity to UNGD operations and the presence of congenital defects, reduced birth weights and APGAR scores. Equally worrisome is the finding that many of the chemicals and metals associated with UNGD are associated with developmental, learning and behavioral disabilities in children. Yet studies that have linked concurrent qualitative and quantitative environmental chemical exposures, maternal and fetal/neonatal tissue chemical concentrations and health outcomes are lacking. Utilizing an equine animal model as a sentinel for human health, we will test the hypothesis that exposure to environmental chemicals is associated with the development of neonatal neurological deficits and impaired maternal reproductive function. The first specific aim is to quantitate air-, water- and pasture forage-borne environmental chemicals during an 18-month reproduction cycle at two separate facilities, one in close proximity to a UNGD operation and the other (control) facility at distant site not exposed to natural resource mining activities. Using passive sampling devices (PSDs) strategically deployed throughout the facilities (air, water) and worn by sentinel animals, polycyclic and oxygenated aromatic hydrocarbons, volatile organic compounds and pesticides will be detected. Water and soil grab samples will be analyzed for metals and trace elements; pasture forage samples will be analyzed for VOCs; feed samples will be analyzed for mycotoxins. The second specific aim is to quantitate environmental chemicals (detected in Aim 1) within animal tissues and correlate their presence with the development of with organ dysfunction, including neurological deficits and reproductive problems. Over the 18-month study period, relevant tissue samples will be obtained to detect evidence of systemic inflammation, organ dysfunction, oxidative stress, alterations in hormone synthesis, abnormalities in neonatal neural development and dam reproduction, and reduced neonatal birth weights and growth rates. The results of our study, which will establish a link between environmental chemical exposure-adverse health outcomes, will serve as the foundation of future investigations of the pathophysiological mechanisms of environmental chemicals exposure. Because the horse is well-suited as an animal model for human diseases, the results and conclusions of our study have relevance to individuals living or working in close proximity to UNGD operations.