Black carbon exposure more strongly associated with census tract poverty compared to household income among US black, white, and Latino working class adults in Boston, MA (2003–2010)

•The study included 1757 black, Latino, and white working class adults in Boston, MA.•Census tract poverty was associated with annual average black carbon exposure.•Annual household income was not associated with black carbon exposure.•Individual-level education was not associated with black carbon exposure.•The observed socioeconomic patterns varied by race/ethnicity.

We investigated the association of individual-level ambient exposure to black carbon (spatiotemporal model-based estimate for latitude and longitude of residential address) with individual, household, and census tract socioeconomic measures among a study sample comprised of 1757 US urban working class white, black and Latino adults (age 25–64) recruited for two studies conducted in Boston, MA (2003–2004; 2008–2010). Controlling for age, study, and exam date, the estimated average annual black carbon exposure for the year prior to study enrollment at the participants' residential address was directly associated with census tract poverty (beta = 0.373; 95% confidence interval (CI) 0.322, 0.423) but not with annual household income or education; null associations with race/ethnicity became significant only after controlling for socioeconomic position.