Differences in Long Term Exposure to Wildfire Smoke Among People Who Are Incarcerated Compared to People Who Are Not...

Wildfire smoke exposure is associated with a range of adverse health outcomes. People who are incarcerated may be especially vulnerable to smoke exposure because, compared to non-incarcerated people, they lack agency to control their exposure. The goal of this study, within California, is to (a) geographically characterize wildfire-attributable PM_2.5 exposure from 2015 to 2020 and (b) to determine whether the burden of wildfire PM_2.5 exposure is higher in neighborhoods that contain carceral facilities compared to neighborhoods without carceral facilities. Data on wildfire-attributable PM_2.5 was linked to census-tract level counts of incarcerated and non-incarcerated populations. Statewide statistics on wildfire-attributable PM_2.5 were calculated for five exposure metrics: (a) number of weeks with wildfire PM_2.5 > 5 μg/m³, (b) number of days with non-zero wildfire PM_2.5, (c) mean daily wildfire PM_2.5 during the peak exposure week, (d) number of smoke waves (defined as ≥2 consecutive days with >15 μg/m³ wildfire PM_2.5), and (e) average of the annual mean wildfire PM_2.5 concentrations. To spatially compare wildfire PM_2.5 exposure among incarcerated people to non-incarcerated neighbors, population-weighted exposure metrics were calculated for each tract containing incarcerated people and compared to surrounding tracts' exposures using non-incarcerated population weights. Across California, census tracts containing incarcerated people had heightened wildfire-attributable PM_2.5 exposures and a large proportion of California's incarcerated population (48.5%) resided in tracts in the highest quartile of non-zero wildfire PM_2.5 days compared to non-incarcerated people (25.9%). Prisons and jails in areas that have high wildfire smoke exposure levels should improve ventilation capabilities, provide protective equipment and develop preparedness plans.