Drinking water, fracking, and infant health

A Narrative Review of Spatial-Temporal Data Sources for Estimating Population-Level Exposures to Oil and Gas Development in the United States

PURPOSE OF REVIEW

Oil and gas development is a rapidly expanding industry that may impact population health. However, much of the research to date is conducted state-by-state, partially due to exposure data limitations. New developments related to national-scale oil and gas development data sources offer the opportunity to extend studies beyond single-state analyses. We review the current data options, highlighting their advantages, disadvantages, and ideal use-cases.

RECENT FINDINGS

Five data sources suitable for national-scale epidemiologic analyses of oil and gas development were identified. Private sector data offer detailed production information but have limited accessibility. Nongovernmental sources are often specialized, focusing on specific aspects like chemical or methane exposure. Government agency data, while typically less detailed, provide useful linkage tools for cross-industry analysis. This review clarifies the strengths and limitations of these sources, facilitating national-level exposure assessment and broadening the geographic reach of oil and gas development-related epidemiology in the U.S.

Influence of aspect ratios on water disinfection efficiency in a serpentine flow channel using ultraviolet C light-emitting diode

The flow channel configuration affects microbial inactivation efficiency in water because it considerably influences hydrodynamics and ultraviolet (UV) light distribution. The ratio of channel length to breadth (α) and the ratio of channel width to depth (β) of a serpentine flow channel on Escherichia coli inactivation efficiency were investigated. Simulations revealed that when α was 1.0, the flow channel had a uniform velocity distribution and performed the longest microbial residence time. Furthermore, biodosimetry tests indicated that when β was 1.0, the reactor resulted in a maximum inactivation efficiency of 3.7 log when the distance between the UV LEDs and the water was 11.5 mm. The optimal aspect ratio β led to the ideal balance between microbial residence time and UV irradiance, resulting in the highest UV fluence (10.6 mJ/cm2) for the bacteria. The inactivation efficiency observed at the aforementioned aspect ratio was approximately 48% higher than that observed at an aspect ratio of 2.56. Additionally, decreasing the distance between the UV LEDs and the water from 11.5 to 3.5 mm enhanced the inactivation efficiency at all aspect ratios because of the considerable increase in UV irradiance in the water.

Variation in Proximity to Oil and Gas Well Pads across Race-Ethnicity and Income Groups in Colorado: An Inquiry into Distributive Environmental Justice Patterns

Proximity to oil and gas (OG) wells is associated with health risks. Evidence on the relationship between sociodemographic characteristics and OG well proximity is mixed. To investigate this question in Colorado, we combined OG location data with data on birthing people's race-ethnicity and Medicaid eligibility from the state's birth registry. We applied two OG proximity definitions: (1) living within 2,000 ft of an active well and (2) OG well density (inverse distance-weighted sum of wells within 2 miles). Our analysis includes people who gave birth between 2007 and 2017 and resided in one of seven OG-producing counties across three different OG basins. In the Denver-Julesburg basin (DJB), which accounted for 93% of the study sample, White and Medicaid ineligible people are more proximate than Hispanic and Medicaid eligible people. In some DJB counties, People of Color (non-Hispanic) are more proximate than Hispanic people. In the Piceance basin, White non-Hispanic people have higher proximity than Hispanic people, while Medicaid eligibility is associated with higher proximity. In the San Juan basin, Hispanic and Medicaid-eligible people were more proximate than White and Medicaid-ineligible people. Further research should examine differential exposure/proximity across other sensitive groups, and policies should pursue equal protection from OG well exposures.

The Causal Effect of Increasing Area-Level Income on Birth Outcomes and Pregnancy-Related Health: Estimates From the Marcellus Shale Boom Economy

Income is positively correlated with pregnancy health and birth outcomes, but the causal evidence for this association is limited. Leveraging a natural experiment based on the Pennsylvania boom economy created by the extraction of natural gas from the Marcellus Shale geological formation, we test whether area-level income gains impact birth outcomes (birth weight, gestational length, and preterm birth) and pregnancy health (prepregnancy and prenatal smoking, prepregnancy weight status, gestational weight gain, and the timing and adequacy of prenatal care). We append tax data to birth certificate data and compare health outcomes before and after the boom for births occurring in school districts above the Marcellus Shale. We also explore income effects with a subsample of siblings and test for nonlinear income effects by considering preboom district poverty rates. Using instrumented difference-in-differences models, we find that plausibly exogenous income gains increase the likelihood of having adequate prenatal care in the full sample. In the sibling sample, income gains decrease the likelihood of low birth weight but increase the likelihood of prepregnancy underweight among birthing parents. Results are statistically significant in initially high-poverty districts. We thus affirm prior findings of a causal effect of income on birth weight and prenatal care use but find minimal area-level income effects on other pregnancy-related health behaviors and birth outcomes.

Wastewaters Coproduced with Shale Gas Drive Slight Regional Salinization of Groundwater

While unconventional oil and gas (UOG) development is changing the world economy, processes that are used during UOG development such as high-volume hydraulic fracturing ("fracking") have been linked with water contamination. Water quality risks include leaks of gas and salty fluids (brines) that are coproduced at wellpads. Identifying the cause of contamination is difficult, however, because UOG wells are often colocated with other contaminant sources. We investigated the world's largest shale gas play with publicly accessible groundwater data (Marcellus Shale in Pennsylvania, U.S.A. with ∼29,000 analyses) and discovered that concentrations of brine-associated barium ([Ba]) and strontium ([Sr]) show small regional increases within 1 km of UOG development. Higher concentrations in groundwaters are associated with greater proximity to and density of UOG wells. Concentration increases are even larger when considering associations with the locations of (i) spill-related violations and (ii) some wastewater impoundments. These statistically significant relationships persist even after correcting for other natural and anthropogenic sources of salts. The most likely explanation is that UOG development slightly increases salt concentrations in regional groundwaters not because of fracking but because of the ubiquity of wastewater management issues. These results emphasize the need for stringent wastewater management practices across oil and gas operations.

The human health effects of unconventional oil and gas development (UOGD): A scoping review of epidemiologic studies

OBJECTIVE

Unconventional oil and gas development (UOGD, sometimes termed "fracking" or "hydraulic fracturing") is an industrial process to extract methane gas and/or oil deposits. Many chemicals used in UOGD have known adverse human health effects. Canada is a major producer of UOGD-derived gas with wells frequently located in and around rural and Indigenous communities. Our objective was to conduct a scoping review to identify the extent of research evidence assessing UOGD exposure-related health impacts, with an additional focus on Canadian studies.

METHODS

We included English- or French-language peer-reviewed epidemiologic studies (January 2000-December 2022) which measured exposure to UOGD chemicals directly or by proxy, and where health outcomes were plausibly caused by UOGD-related chemical exposure. Results synthesis was descriptive with results ordered by outcome and hierarchy of methodological approach.

SYNTHESIS

We identified 52 studies from nine jurisdictions. Only two were set in Canada. A majority (n = 27) used retrospective cohort and case-control designs. Almost half (n = 24) focused on birth outcomes, with a majority (n = 22) reporting one or more significant adverse associations of UOGD exposure with: low birthweight; small for gestational age; preterm birth; and one or more birth defects. Other studies identified adverse impacts including asthma (n = 7), respiratory (n = 13), cardiovascular (n = 6), childhood acute lymphocytic leukemia (n = 2), and all-cause mortality (n = 4).

CONCLUSION

There is a growing body of research, across different jurisdictions, reporting associations of UOGD with adverse health outcomes. Despite the rapid growth of UOGD, which is often located in remote, rural, and Indigenous communities, Canadian research on its effects on human health is remarkably sparse. There is a pressing need for additional evidence.

Health equity in pediatrics: Current concepts for the care of children in the 21st century (Dis Mon)

This is an analysis of important aspects of health equity in caring for children and adolescents written by a multidisciplinary team from different medical centers. In this discussion for clinicians, we look at definitions of pediatric health equity and the enormous impact of social determinants of health in this area. Factors involved with pediatric healthcare disparities that are considered include race, ethnicity, gender, age, poverty, socioeconomic status, LGBT status, living in rural communities, housing instability, food insecurity, access to transportation, availability of healthcare professionals, the status of education, and employment as well as immigration. Additional issues involved with health equity in pediatrics that are reviewed will include the impact of the COVID-19 pandemic, behavioral health concepts, and the negative health effects of climate change. Recommendations that are presented include reflection of one's own attitudes on as well as an understanding of these topics, consideration of the role of various healthcare providers (i.e., community health workers, peer health navigators, others), the impact of behavioral health integration, and the need for well-conceived curricula as well as multi-faceted training programs in pediatric health equity at the undergraduate and postgraduate medical education levels. Furthermore, ongoing research in pediatric health equity is needed to scrutinize current concepts and stimulate the development of ideas with an ever-greater positive influence on the health of our beloved children. Clinicians caring for children can serve as champions for the optimal health of children and their families; in addition, these healthcare professionals are uniquely positioned in their daily work to understand the drivers of health inequities and to be advocates for optimal health equity in the 21st century for all children and adolescents.

The Siren Song of Cicadas: Early-Life Pesticide Exposure and Later-Life Male Mortality

This paper studies the long-term effects of in-utero and early-life exposure to pesticide use on adulthood and old-age longevity. We use the cyclical emergence of cicadas in the eastern half of the United States as a shock that raises the pesticide use among tree crop growing farmlands. We implement a difference-in-difference framework and employ Social Security Administration death records over the years 1975-2005 linked to the complete count 1940 census. We find that males born in top-quartile tree-crop counties and exposed to a cicada event during fetal development and early-life live roughly 2.2 months shorted lives; those with direct farm exposure face a reduction of nearly a year. We provide empirical evidence to examine mortality selection before adulthood, endogenous fertility, and differential data linkage rates. Additional analyses suggests that reductions in education and income during adulthood are potential mechanisms of impact. Our findings add to our understanding of the relevance of early-life insults for old-age health and mortality.

Drinking Water Contaminant Concentrations and Birth Outcomes

Previous research in the US has found negative health effects of contamination when it triggers regulatory violations. An important question is whether levels of contamination that do not trigger a health-based violation impact health. We study the impact of drinking water contamination in community water systems on birth outcomes using drinking water sampling results data in Pennsylvania. We focus on the effects of water contamination for births not exposed to regulatory violations. Our most rigorous specification employs mother fixed effects and finds changing from the 10th to the 90th percentile of water contamination (among births not exposed to regulatory violations) increases low birth weight by 12% and preterm birth by 17%.

Social Vulnerability and Groundwater Vulnerability to Contamination From Unconventional Hydrocarbon Extraction in the Appalachian Basin

Unconventional oil and gas (UOG) development, made possible by horizontal drilling and high-volume hydraulic fracturing, has been fraught with controversy since the industry's rapid expansion in the early 2000's. Concerns about environmental contamination and public health risks persist in many rural communities that depend on groundwater resources for drinking and other daily needs. Spatial disparities in UOG risks can pose distributive environmental injustice if such risks are disproportionately borne by marginalized communities. In this paper, we analyzed groundwater vulnerability to contamination from UOG as a physically based measure of risk in conjunction with census tract level sociodemographic characteristics describing social vulnerability in the northern Appalachian Basin. We found significant associations between elevated groundwater vulnerability and lower population density, consistent with UOG development occurring in less densely populated rural areas. We also found associations between elevated groundwater vulnerability and lower income, higher proportions of elderly populations, and higher proportion of mobile homes, suggesting a disproportionate risk burden on these socially vulnerable groups. We did not find a statistically significant association between elevated groundwater vulnerability and populations of racial/ethnic minorities in our study region. Household surveys provided empirical support for a relationship between sociodemographic characteristics and capacity to assess and mitigate exposures to potentially contaminated water. Further research is needed to probe if the observed disparities translate to differences in chemical exposure and adverse health outcomes.

It's electric! An environmental equity perspective on the lifecycle of our energy sources

Energy policy decisions are driven primarily by economic and reliability considerations, with limited consideration given to public health, environmental justice, and climate change. Moreover, epidemiologic studies relevant for public policy typically focus on immediate public health implications of activities related to energy procurement and generation, considering less so health equity or the longer-term health consequences of climate change attributable to an energy source. A more integrated, collective consideration of these three domains can provide more robust guidance to policymakers, communities, and individuals. Here, we illustrate how these domains can be evaluated with respect to natural gas as an energy source. Our process began with a detailed overview of all relevant steps in the process of extracting, producing, and consuming natural gas. We synthesized existing epidemiologic and complementary evidence of how these processes impact public health, environmental justice, and climate change. We conclude that, in certain domains, natural gas looks beneficial (e.g., economically for some), but when considered more expansively, through the life cycle of natural gas and joint lenses of public health, environmental justice, and climate change, natural gas is rendered an undesirable energy source in the United States. A holistic climate health equity framework can inform how we value and deploy different energy sources in the service of public health.

Examining the association between safe drinking water act violations and adverse birth outcomes in Virginia

In 1974, the United States established the Safe Drinking Water Act (SDWA) to protect consumers from potential exposure to drinking water contaminants associated with health risks. Each contaminant is assigned a health-based standard meant to reflect the maximum level at which an adverse human health outcome is unlikely; measurements beyond that level have greater potential to result in adverse health outcomes. Although there is extensive research on human health implications following water contaminant exposure, few studies have specifically examined associations between fetal health and municipal drinking water violations. Therefore, the objective of this study is to assess whether SDWA drinking water violations are associated with fetal health outcomes, including preterm birth (PTB), low birth weight (LBW), and term-low birth weight (tLBW), in the Commonwealth of Virginia. Singleton births (n = 665,984) occurring between 2007 and 2015 in Virginia were geocoded and assigned to a corresponding estimated water service area. Health-based (HB) and monitoring and reporting (MR) violations for 12 contaminants were acquired from the US EPA Safe Drinking Water Information System, with exposure defined at the approximate service area level to limit exposure misclassification. A logistic regression model for each birth outcome assessed potential relationships with SDWA violations. When examining the association between individual MR violations and birth outcomes, Nitrate-Nitrite (OR = 1.10; 95% CI = 1.02, 1.18, P = 0.01) was positively associated with PTB and the total coliform rule was negatively associated with tLBW (OR = 0.93; 95% CI = 0.87, 1.00, P = 0.04). These findings indicate that a lack of regular monitoring and reporting by water providers (resulting in monitoring and reporting violations) may be concealing health-based violations as these health concerns cannot be revealed without testing, suggesting a need for additional technical, managerial, and financial support to enable often-underfunded water systems to adhere to monitoring and reporting requirements meant to protect public health.

Assessing Exposure to Unconventional Oil and Gas Development: Strengths, Challenges, and Implications for Epidemiologic Research

PURPOSE OF REVIEW

Epidemiologic studies have observed elevated health risks in populations living near unconventional oil and gas development (UOGD). In this narrative review, we discuss strengths and limitations of UOG exposure assessment approaches used in or available for epidemiologic studies, emphasizing studies of children's health outcomes.

RECENT FINDINGS

Exposure assessment challenges include (1) numerous potential stressors with distinct spatiotemporal patterns, (2) critical exposure windows that cover long periods and occur in the past, and (3) limited existing monitoring data coupled with the resource-intensiveness of collecting new exposure measurements to capture spatiotemporal variation. All epidemiologic studies used proximity-based models for exposure assessment as opposed to surveys, biomonitoring, or environmental measurements. Nearly all studies used aggregate (rather than pathway-specific) models, which are useful surrogates for the complex mix of potential hazards. Simple and less-specific exposure assessment approaches have benefits in terms of scalability, interpretability, and relevance to specific policy initiatives such as set-back distances. More detailed and specific models and metrics, including dispersion methods and stressor-specific models, could reduce exposure misclassification, illuminate underlying exposure pathways, and inform emission control and exposure mitigation strategies. While less practical in a large population, collection of multi-media environmental and biological exposure measurements would be feasible in cohort subsets. Such assessments are well-suited to provide insights into the presence and magnitude of exposures to UOG-related stressors in relation to spatial surrogates and to better elucidate the plausibility of observed effects in both children and adults.

Where you drink water: An assessment of the Tennessee, USA public water supply

Monitoring drinking water quality is essential to protect people's health and wellbeing. In the United States, the Safe Drinking Water Information System (SDWIS) database records the occurrence of a drinking water violation regulation in public water systems. A notable shortcoming of SDWIS is the lack of the contaminant concentration level about the allowable maximum contaminant threshold. In this study, we take advantage of both the SDWIS violation database and the contaminants sampling database at the state level to examine the drinking water quality of all kinds of drinking water systems in detail. We obtained sampling data (i.e., the concentration level of contaminants) of public water systems (PWSs) in Tennessee and explored the statistical distribution of contaminant concentration data in relation to the enforceable maximum regulatory contaminant level). We use both SDWIS violation records and actual concentrations of contaminants from the sampling data to study the factors that influence the drinking water quality of PWSs. We find that different types of violations were more frequent in (1) specific geological regions, (2) counties with PWSs that serve a larger population (10,000 to 100,000 people), and (3) places with abundant surface water, such as near a lake or major river. Additionally, the distribution of measured concentrations for many contaminants was not smooth but was punctuated by discontinuities at selected levels, such as at 50% of the maximum contaminant level. Such anomalies in the sampling data do not indicate violations, but more investigation is needed to determine the reasons behind the punctuated changes.