Ancestry-based intracategorical injustices in carcinogenic air pollution exposures in the United States

Evaluating disparities in air pollution as a function of ethnicity, deprivation and sectoral emissions in England

Macro-scale distribution of air pollution concentrations is influenced by factors including geography, weather, industry, transport and regulation. Pollution sources are unevenly distributed, with some communities disproportionately impacted by higher emissions. This study separates the effects of deprivation from ethnicity as factors that influence proximity to pollution sources. We combine recent decadal census data (2021) on socioeconomic deprivation and detailed population ethnicity at fine scales (Lower Super Output layer Area, LSOA n = 1600 people) with a 1×1 km sector-resolved atmospheric emissions inventory for NOx and primary PM2.5 in England. All 24 minoritised ethnic groups studied experienced higher average local NOx and PM2.5 emissions than socio-economically matched populations in the majority 'White: English, Welsh, Scottish, Northern Irish or British' ethnic group. Chinese, Arab and Bangladeshi communities experienced the largest disparity in NOx, with weighted emissions 100%, 91%, 89% higher than white populations of matched deprivation status. Bangladeshi, Pakistani and Roma groups experienced on average 40%, 40%, 36% higher PM2.5 emissions locally than matched white groups. For NOx the largest contributors leading to disparity, were road transport (48%), domestic combustion (23%) and industry (15%). For PM2.5 the greatest contributors to disparity were domestic combustion (53%), road transport (19%), and industry (11%). Living near to road transport and in city centres are frequently cited as primary drivers of ethnicity and deprivation-based disparities, however the analysis identifies that industrial, domestic and off-road sources create issues of the same magnitude, and disparities remain in suburban settings, smaller towns and some rural areas.

Sociodemographic inequities in the burden of carcinogenic industrial air emissions in the United States

BACKGROUND

Industrial facilities are not located uniformly across communities in the United States, but how the burden of exposure to carcinogenic air emissions may vary across population characteristics is unclear. We evaluated differences in carcinogenic industrial pollution among major sociodemographic groups in the United States and Puerto Rico.

METHODS

We evaluated cross-sectional associations of population characteristics including race and ethnicity, educational attainment, and poverty at the census tract level with point-source industrial emissions of 21 known human carcinogens using regulatory data from the US Environmental Protection Agency. Odds ratios and 95% confidence intervals comparing the highest emissions (tertile or quintile) to the referent group (zero emissions [ie, nonexposed]) for all sociodemographic characteristics were estimated using multinomial, population density-adjusted logistic regression models.

RESULTS

In 2018, approximately 7.4 million people lived in census tracts with nearly 12 million pounds of carcinogenic air releases. The odds of tracts having the greatest burden of benzene, 1,3-butadiene, ethylene oxide, formaldehyde, trichloroethylene, and nickel emissions compared with nonexposed were 10%-20% higher for African American populations, whereas White populations were up to 18% less likely to live in tracts with the highest emissions. Among Hispanic and Latino populations, odds were 16%-21% higher for benzene, 1,3-butadiene, and ethylene oxide. Populations experiencing poverty or with less than high school education were associated with up to 51% higher burden, irrespective of race and ethnicity.

CONCLUSIONS

Carcinogenic industrial emissions disproportionately impact African American and Hispanic and Latino populations and people with limited education or experiencing poverty thus representing a source of pollution that may contribute to observed cancer disparities.

Inequalities in Environmental Cancer Risk and Carcinogen Exposures: A Scoping Review

Background: Cancer is the leading cause of death in Canada and a major cause of death worldwide. Environmental exposure to carcinogens and environments that may relate to health behaviors are important to examine as they can be modified to lower cancer risks. Built environments include aspects such as transit infrastructure, greenspace, food and tobacco environments, or land use, which may impact how people move, exercise, eat, and live. While environments may play a role in overall cancer risk, exposure to carcinogens or healthier environments is not equitably spread across space. Exposures to carcinogens commonly concentrate among socially and/or economically disadvantaged populations. While many studies have examined inequalities in exposure or cancer risk, this has commonly been for one exposure. Methods: This scoping review collected and synthesized research that examines inequities in carcinogenic environments and exposures. Results: This scoping review found that neighborhoods with higher proportions of low-income residents, racialized people, or same-sex couples had higher exposures to carcinogens and environments that may influence cancer risk. There are currently four main themes in research studying inequitable exposures: air pollution and hazardous substances, tobacco access, food access, and other aspects of the built environment, with most research still focusing on air pollution. Conclusions: More work is needed to understand how exposures to these four areas intersect with other factors to reduce inequities in exposures to support longer-term goals toward cancer prevention.

Intersectional inequalities in industrial air toxics exposure in the United States

Environmental justice and health research demonstrate unequal exposure to environmental hazards at the neighborhood-level. We use an innovative method-eco-intersectional multilevel (EIM) modeling-to assess intersectional inequalities in industrial air toxics exposure across US census tracts in 2014. Results reveal stark inequalities in exposure across analytic strata, with a 45-fold difference in average exposure between most and least exposed. Low SES, multiply marginalized (high % Black, high % female-headed households) urban communities experienced highest risk. These inequalities were not described by additive effects alone, necessitating the use of interaction terms. We advance a critical intersectional approach to evaluating environmental injustices.

Study the forest, not only the trees: Environmental exposures, not genomes, generate most health disparities

As sequencing and analysis techniques provide increasingly detailed data at a plummeting cost, it is increasingly popular to seek the answers to medical and public health challenges in the DNA sequences of affected populations. This is methodologically attractive in its simplicity, but a genomics-only approach ignores environmentally mediated health disparities, which are well-documented at multiple national and global scales. While genetic differences exist among populations, it is unlikely that these differences overcome social and environmental factors in driving the gap in health outcomes between privileged and oppressed communities. We advocate for following the lead of communities in addressing their self-identified interests, rather than treating widespread suffering as a convenient natural experiment.

Differential Access to Park Space Based on Country of Origin within Miami's Hispanic/Latino Population: A Novel Analysis of Park Equity

Some U.S.-based park equity studies reveal that affluent and White neighborhoods have privileged access to greenspace. In such studies in the U.S. and elsewhere, park access indicators are typically examined in relation to measures of income, housing tenure, and broad race/ethnicity categories (e.g., Hispanic/Latino, Black, and White in the U.S.). The treatment of people as monolithic ethnic groups in park equity research is potentially misleading, particularly in global cities where ethnic populations are highly heterogeneous. In this study, we assess inequities in access to park space within the diverse Hispanic/Latino population of the Miami Metropolitan Statistical Area (MSA) based on national origin. We specified multivariable generalized estimating equations to examine social correlates of area-weighted park access at the census tract level. Our first model includes a variable for the proportion of the tract population of Hispanic/Latino ethnicity, which we substitute in the second model with variables representing the proportions of the tract population from the most populous country-of-origin groups in the MSA applicable to the Hispanic/Latino population. Our first model indicates robust negative relationships for the proportion Hispanic/Latino and Black/African American variables with area-weighted park access, adjusting for median household income, renter-occupancy, and old and young population composition. Our second model indicates negative relationships based on Cuban and Venezuelan neighborhood composition, while the four other country-of-origin subgroup variables exhibit statistically non-significant associations with area-weighted park access. Study findings have implications for the analysis of ethnicity categories in park equity research and interventions to promote park equity, especially in global cities.