Racial/ethnic disparities in tuberculosis incidence linked to PM2.5 constituents and their sources in the United States, 2000 - 2019: a population-based study.

BACKGROUND

Racial/ethnic disparities in the effects of PM2.5 constituents and their sources on tuberculosis (TB) incidence remain unclear.

METHODS

We collected data on TB incidence in 49 states of the United States (US) during 2000 - 2019. Two-way fixed effects models were employed to assess the effects of 15 PM2.5 constituents, and the non-negative matrix factorization analysis was additionally performed to explore the effects of sources of PM2.5 constituents. The generalized weighted quantile sum method was applied to determine the relative contribution of each PM2.5 constituent. Racial/ethnic disparities were evaluated in the form of absolute and relative disparities.

RESULTS

Effects of most PM2.5 constituents on TB incidence in the Hispanic people were stronger than those in others, with an interquartile range increase in constituents associated with 1.25 (95% CI: 0.48 to 2.02 for potassium) to 4.10 (95% CI: 3.27 to 4.94 for sulfate) additional TB cases per 100,000 individuals annually in the Hispanic people. The absolute disparity in PM2.5-attributable TB burden between the Hispanic and White people decreased from 11.07 to 6.48 cases per 100,000 individuals, while the relative disparity enlarged from 15.75 in 2000 to 16.17 in 2019. Sulfate was the most influential constituent to TB incidence for the White (32.0%), Hispanic people (26.1%), and people of other races/ethnicities (17.9%). PM2.5 from oil combustion/motor vehicle traffic increased TB incidence in the Hispanic people and people of other races/ethnicities. TB incidence was positively associated with PM2.5 from biomass and coal burning across most of races/ethnicities.

CONCLUSIONS

More efforts targeted at the Hispanic people are needed to narrow the PM2.5-attributable racial/ethnic health inequities in TB. Reducing PM2.5 from oil combustion/motor vehicle traffic, biomass and coal burning would contribute to TB elimination in the US.