Short-Term total and wildfire fine particulate matter exposure and work loss in California

Few studies investigated the impact of particulate matter (PM_2.5) on some symptom exacerbations that are not perceived as severe enough to search for medical assistance. We aimed to study the association of short-term daily total PM_2.5 exposure with work loss due to sickness among adults living in California.

We included 44,544 adult respondents in the workforce from 2015 to 2018 California Health Interview Survey data. Daily total PM_2.5 concentrations were linked to respondents' home addresses from continuous spatial surfaces of PM_2.5 generated by a geostatistical surfacing algorithm. We estimated the effect of a 2-week average of daily total PM_2.5 exposure on work loss using logistic regression models.

About 1.69% (weighted percentage) of adult respondents reported work loss in the week before the survey interview. The odds ratio of work loss was 1.45 (odds ratio [OR] = 1.45, 95% confidence interval [CI]: 1.03, 2.03) when a 2-week average of daily total PM_2.5 exposure was higher than 12 µg/m³. The OR for work loss was 1.05 (95% CI: 0.98, 1.13) for each 2.56ug/m³ increase in the 2-week average of daily total PM_2.5 exposure, and became stronger among those who were highly exposed to wildfire smoke (OR = 1.06, 95% CI: 1.00, 1.13), compared to those with lower wildfire smoke exposure (OR = 1.04, 95% CI: 0.79, 1.39).

Our findings suggest that short-term ambient PM_2.5 exposure is positively associated with work loss due to sickness and the association was stronger among those with higher wildfire smoke exposure. It also indicated that the current federal and state PM_2.5 standards (annual average of 12 µg/m³) could be further strengthened to protect the health of the citizens of California.