Temporal Trends of Racial and Socioeconomic Disparities in Population Exposures to Upstream Oil and Gas Development in California

Inequality in Hazardous Air Pollutant Emissions and Concentrations Measured Over Los Angeles

In Los Angeles, air pollution disproportionately impacts communities of color and low-income residents. Routine city-wide measurements of hazardous air pollutants (HAPs), of concern for health and contributing to urban air pollution, are notably lacking. In this study, we use the highest spatially resolved (∼2 km) measurements of emissions and concentrations ever reported of HAPs while covering a whole megacity and combine observations with US Census information. We observe higher concentrations and emissions of 17 measured HAPs, such as benzene, naphthalene, and p-chlorobenzotrifluoride (PCBTF), in California-designated Disadvantaged Communities (DACs) and census tracts with low-income Hispanics and Asians. These groups share an unequal burden from traffic-related emissions, with benzene, nitrogen oxides (NOx), and carbon monoxide (CO) concentrations up to 60% higher. However, in DACs and census tracts with large Hispanic populations (>50%), we observe toluene-to-benzene emission ratios above 3, pointing to inequalities in other HAPs primarily caused by non-traffic emission sources such as industry and solvents. In these communities, regulatory inventories also significantly underestimate emissions. We find that efforts to address HAP inequalities and environmental justice concerns in Los Angeles will need to consider contributions from volatile chemical products, which represent a growing source of emissions driving inequalities in impacted communities.

Environmental justice implications of hydraulic fracturing: A spatio-temporal analysis in Texas

This study contributes to the field of environmental justice by addressing two key questions: (1) To what extent are racial and ethnic composition, socio-demographic characteristics, and housing-related factors associated with the siting of hydraulic fracturing wells in the U.S.? and (2) How have these associations evolved over time, and have demographic changes contributed to increased environmental justice concerns? Using a panel dataset from FracFocus and the American Community Survey at the census-tract level between 2011 and 2023, the findings reveal that hydraulic fracturing wells are disproportionately located near census tracts with higher percentages of Black and Hispanic populations, indicating environmental injustice towards racial minorities. These findings remain consistent across alternative proximity measures, including different distance buffers and population exposure estimates using area interpolation. Moreover, the longitudinal analysis suggests a growing trend in well placement near marginalized communities in recent years. This pattern may be attributed to post-siting demographic change, where minority populations, particularly Hispanic residents, are increasingly concentrated in areas near fracking sites, while White populations gradually relocate farther away. These findings underscore our contribution to new empirical evidence that can inform communities and policymakers about the distributional impacts of fracking activities.

Sociodemographic and Population Exposure to Upstream Oil and Gas Operations in Canada

Canada, as one of the largest oil and gas producer in the world, is responsible for large emissions of methane, a powerful greenhouse gas. At low levels, methane is not a direct threat to human health; however, human health is affected by exposure to pollutants co-emitted with methane. The objectives of this research were to estimate and map pollutants emitted by the oil and gas industry, to assess the demographic of the population exposed to oil and gas activities, and to characterize the impact of well density on cardiovascular- and respiratory-related outcomes with a focus on Alberta. We estimated that ~13% and 3% people in Alberta reside, respectively, within 1.5 km of an active well and 1.5 km of a flare. Our analysis suggests that racial and socioeconomic disparities exist in residential proximity to active wells, with people of Aboriginal identity and people with less education being more exposed to active wells than the general population. We found increased odds of cardiovascular-related (1.13-1.29 for low active well density) and respiratory-related (1.07-1.19 for low active well density) outcomes with exposure to wells. Close to 100 countries produce oil and gas, making this a global issue. There is an important need for additional studies from other producing jurisdictions outside the United States.

Upstream Oil and Gas Production and Community COVID-19 Case and Mortality Rates in California, USA

Higher concentrations of ambient air pollutants, including PM2.5 and NO2, and other pollutants have been found near active oil and gas wells and may be associated with adverse COVID-19 outcomes. We assessed whether residential exposure to nearby oil and gas production was associated with higher rates of the respiratory infection COVID-19 and related mortality using a population-based ecological study in California. Using gridded population estimates, we estimated area-level exposure to annual average oil and gas production volume from active wells within 1 kilometer (km) of populated areas within census block groups from 2018 to 2020. We geocoded confirmed cases and associated deaths to assess block group case and mortality rates from COVID-19 from February 2020 to January 2021. We fit hierarchical Poisson models with individual and area covariates (e.g., age, sex, socioeconomic disadvantage), and included time and other interactions to assess additional variation (e.g., testing, reporting rates). In the first 4 months of the study period (February-May 2020), block groups in the highest tertile of oil and gas production exposure had 34% higher case rates (IRR: 1.34 95% CI: 1.20, 1.49) and 55% higher mortality rates (MRR: 1.52 95%: CI: 1.14, 2.03) than those with no estimated production, after accounting for area-level covariates. Over the entire study period, we observed moderately higher mortality rates in the highest group (MRR: 1.16 95%: CI: 1.01, 1.33) and null associations for case rates.

Wildfires increasingly threaten oil and gas wells in the western United States with disproportionate impacts on marginalized populations

The western United States is home to most of the nation's oil and gas production and, increasingly, wildfires. We examined historical threats of wildfires for oil and gas wells, the extent to which wildfires are projected to threaten wells as climate change progresses, and exposure of human populations to these wells. From 1984-2019, we found that cumulatively 102,882 wells were located in wildfire burn areas, and 348,853 people were exposed (resided ≤ 1 km). During this period, we observed a five-fold increase in the number of wells in wildfire burn areas and a doubling of the population within 1 km of these wells. These trends are projected to increase by late century, likely threatening human health. Approximately 2.9 million people reside within 1 km of wells in areas with high wildfire risk, and Asian, Black, Hispanic, and Native American people have disproportionately high exposure to wildfire-threatened wells.

Race, Racism, and Drinking Water Contamination Risk From Oil and Gas Wells in Los Angeles County, 2020

Objectives. To evaluate the potential for drinking water contamination in Los Angeles (LA) County, California, based on the proximity of supply wells to oil and gas wells, and characterize risk with respect to race/ethnicity and measures of structural racism. Methods. We identified at-risk community water systems (CWSs) as those with supply wells within 1 kilometer of an oil or gas well. We characterized sociodemographics of the populations served by each CWS by using the 2013-2017 American Community Survey. We estimated the degree of redlining in each CWS service area by using 1930s Home Owners' Loan Corporation security maps, and characterized segregation by using the Index of Concentration at the Extremes. Multivariable regression models estimated associations between these variables and CWS contamination risk. Results. A quarter of LA County CWSs serving more than 7 million residents have supply wells within 1 kilometer of an oil or gas well. Higher percentages of Hispanic, Black, and Asian/Pacific Islander residents and a greater degree of redlining and residential segregation were associated with higher contamination risk. Conclusions. Redlining and segregation predict drinking water contamination risks from oil development in LA County, with people of color at greater risk. (Am J Public Health. 2023;113(11):1191-1200. https://doi.org/10.2105/AJPH.2023.307374).