Date of Award

January 2013

Document Type

Open Access Thesis

Degree Name

Master of Public Health (MPH)


School of Public Health

First Advisor

Meredith H. Stowe


Abstract-- The Marcellus formation supports an advanced rate of extraction of shale-based natural gas, particularly as a result of the rapid development of directional drilling and hydraulic fracturing technologies. The confluence of these trends has spurred public concern about potential health impacts on residents that live in proximity to the putative environmental exposures related to the extraction activities, in largely rural communities of the Marcellus region.

A cross-sectional survey of 492 persons and 580 companion / backyard animals from 180 randomly selected households in an area of active unconventional natural gas drilling was conducted. Cluster analyses were performed to identify significant human and animal-sentinel health events of a priori interest. Frequency of reported dermal, respiratory, gastrointestinal, cardiovascular, and / or neurological symptoms amongst household humans and animals were further assessed to determine if they differed according to gas well proximity and density, by constructing two hierarchical logistic regression models, each based on either Euclidean distance or integrated dispersion density functions.

Spatial scanning revealed clusters of respiratory and dermal events for humans, overlaying regions of the study area with highest density of gas wells. Animal-sentinel events significantly overlapped with similar dermal and respiratory event clusters. While increased prevalence of dermal complaints among residents were observed in a dose-response fashion with increasing proximity, and dermal symptoms also correlated with gas well density, such associations where not evident for other symptom outcomes. Moreover, frequency of concordant symptom outcomes amongst dogs and large animal livestock (i.e. beef and dairy cattle) was not significantly associated with distance and density of gas wells.

Proximity and density of natural gas wells may be related to increased odds of experiencing skin symptoms. Companion and livestock animals may serve as useful sentinel species for early detection of potential irritant effects, related to nearby natural gas extraction activity. However, further investigation regarding sources and routes of exposure is warranted.


This is an Open Access Thesis.

Open Access

This Article is Open Access