Sexual Orientation, Gender, and Environmental Injustice: Unequal Carcinogenic Air Pollution Risks in Greater Houston.

Disparate residential hazard exposures based on disadvantaged gender status (e.g., among female-headed households) have been documented in the distributive environmental justice literature, yet no published studies have examined whether disproportionate environmental risks exist based on minority sexual orientation. To address this gap, we use data from the US Census, American Community Survey and the Environmental Protection Agency at the 2010 census tract level to examine the spatial relationships between same-sex partner households and cumulative cancer risk from exposure to hazardous air pollutants (HAPs) emitted by all ambient emission sources in Greater Houston (Texas). Findings from generalized estimating equation analyses demonstrate that increased cancer risks from HAPs are significantly associated with neighborhoods having relatively high concentrations of resident same-sex partner households, adjusting for geographic clustering and variables known to influence risk (i.e., race, ethnicity, socioeconomic status, renter status, income inequality, and population density). However, HAP exposures are distributed differently for same-sex male versus same-sex female partner households. Neighborhoods with relatively high proportions of same-sex male partner households are associated with significantly greater exposure to cancer-causing HAPs while those with high proportions of same-sex female partner households are associated with less exposure. This study provides initial empirical documentation of a previously unstudied pattern, and infuses current theoretical understanding of environmental inequality formation with knowledge emanating from the sexualities and space literature. Practically, results suggest that other documented health risks experienced in gay neighborhoods may be compounded by disparate health risks associated with harmful exposures to air toxics.