Unconventional natural gas development and adverse birth outcomes in Pennsylvania: The potential mediating role of antenatal anxiety and depression

Abstract

Background: Studies have reported associations between unconventional natural gas development (UNGD) and adverse birth outcomes. None have evaluated potential mediating mechanisms. Objectives: To evaluate associations between (1) UNGD and antenatal anxiety and depression and (2) antenatal anxiety and depression and preterm birth (< 37 weeks gestation) and reduced term birth weight, (3) stochastic direct and indirect effects of UNGD on preterm birth and term birth weight operating through antenatal anxiety and depression, and (4) effect modification by family-level socioeconomic status. Methods: This retrospective cohort study included mothers without prevalent anxiety or depression at time of conception, who delivered at Geisinger in Pennsylvania between January 2009-January 2013. We assembled phase-specific UNGD activity data from public sources. Mothers were categorized as exposed (quartile 4) or unexposed (quartiles 1-3) based on average daily inverse distance-squared UNGD activity metric between conception and the week prior to anxiety or depression (cases) or the pregnancy-average daily metric (noncases). We estimated associations with a doubly robust estimator (targeted minimum loss-based estimation) and adjusted for potential individual-and community-level confounding variables. Results: Analyses included 8,371 births to 7,715 mothers, 12.2% of whom had antenatal anxiety or depression. We found 4.3 additional cases of antenatal anxiety or depression per 100 women (95% CI: 1.5, 7.0) under the scenario where all mothers lived in the highest quartile of UNGD activity versus quartiles 1-3. The risk difference appeared larger among mothers receiving Medical Assistance (indicator of low family income) compared to those who did not, 5.6 (95% CI: 0.5, 10.6) versus 2.9 (95% CI:-0.7, 6.5) additional cases of antenatal anxiety or depression per 100 women. We found no relationship between antenatal anxiety or depression and adverse birth outcomes and no mediation effect either overall or when stratifying by Medical Assistance. Conclusion: We observed a relationship between UNGD activity and antenatal anxiety and depression, which did not mediate the overall association between UNGD activity and adverse birth outcomes.

Shale Gas Development and Community Distress: Evidence from England

“…An increasing number of studies find that residents living near unconventional hydraulic fracturing sites suffer from poor mental health, including elevated levels of stress [ 2 , 4 , 6 , 16 , 17 , 19 ]. Nevertheless, additional research is needed, especially in countries other than the United States where findings may not be replicated.…”

“…Hydraulic fracturing that accompanies shale gas development is stressful because it is perceived to threaten physical health [ 4 , 19 , 20 ]. Brasier et al [ 2 ] (p. 38) learned that health experts in Pennsylvania were concerned about hydraulic fracturing and shale gas development, saying “we’ve done a number of assessments…there are some community perceptions that there are some health issues.” Fisher et al [ 19 ] also uncovered that residents in two Ohio (USA) counties that lived within 5 miles of hydraulic fracturing well faced considerable levels of stress due to their health concerns about those wells.…”

“…An emerging set of literature suggests that this type of development might have a negative impact on the mental health of residents living near extraction sites [ 1 , 2 , 3 ]. In particular, recent studies carried out the in the United States (US) suggest that residing near active hydraulic fracturing wells can lead to poor mental health outcomes [ 4 , 5 , 6 ]. Moreover, in the UK, issue of community stress in shale gas communities, even at the exploration stage, has been raised as a major concern [ 7 , 8 ].…”

Air Monitoring Stations Far Removed From Drilling Activities Do Not Represent Residential Exposures to Marcellus Shale Air Pollutants. Response to the Paper by Hess et al. on Proximity-Based Unconventional Natural Gas Exposure Metrics

“…The epidemiological studies that have used the proximity WA or similar models have all observed the greatest health implications in the densest areas of O&G well activity, generally at residences within 20 km of a well [2,[4][5][6][7][8][9][10][11][12][13][14][15]. McMullin et al (2018) recently evaluated air pollution measured from monitors at distances from O&G wells ranging from 0.1 km to 1.13 km to the closest O&G site and found a number of VOCs, notably benzene, ethylbenzene, and n-nonane [16].…”

“…In fact, the metric was designed to capture complex, multifactorial exposures, including air, water, noise, and light pollution as well as community disruption, psychosocial stress, increased traffic, and other potential impacts related to O&G activity [19]. Most prior epidemiologic studies note this [2,[4][5][6][7][8][9][10][11][12][13][14][15] and acknowledge the limitations of using a WA metric. Therefore, Hess et al have misinterpreted the purpose of the WA metric.…”