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

Associations between particulate matter exposure during pregnancy and executive function of toddlers in a prospective cohort study

BACKGROUND

Exposure to particulate matter (PM) has been found to be associated with impaired cognitive function. However, limited evidence is available on the relationship between PM exposure in the prenatal period and toddler executive function (EF), and the potential influence of breastfeeding.

METHODS

The study included 1106 mother-toddler pairs recruited between 2015 and 2019. We assessed mothers' PM1, PM2.5, and PM10 prenatal exposure with a satellite-based dataset at a 1 × 1 km spatial resolution and assigned to participants based on residential addresses. Toddler EF was measured using the Behavior Rating Inventory of Executive Function for Preschoolers (BRIEF-P) questionnaire, higher BRIEF-P scores indicated poorer EF in toddlers. We determined the associations of PM exposure during pregnancy with BRIEF-P scores using multiple linear regression models.

RESULTS

In the first trimester, a 10 μg/m3 increase of PM was associated with 1.49 (95% confidence interval [CI]: 0.14-2.83; PM1), 0.68 (95% CI: 0.10-1.26; PM2.5), and 0.63 (95% CI: 0.07-1.20; PM10) elevated toddler global executive composite index scores, respectively. In the stratified analysis, a 10 μg/m3 increase in first trimester PM1 exposure was related to 0.54 (95% CI: 0.19-0.89) higher inhibition scores in toddlers who received complementary breastfeeding for less than six months and -0.15 (95% CI: 0.81-0.51) higher inhibition scores in toddlers who received complementary breastfeeding for six months or more (P for interaction: 0.046). Additionally, a 10 μg/m3 increment in first trimester PM1 exposure was related to 0.36 (95% CI: 0.13-0.59) higher emotional control scores in toddlers who received breastfeeding for less than 12 months and -0.54 (95% CI: 1.25-0.18) higher inhibition scores in toddlers who received breastfeeding for no less than 12 months (P for interaction: 0.043).

CONCLUSIONS

PM exposure during the first trimester, especially PM1, has been linked to lower toddler EF performance in toddlers; feeding with breast milk may be a potential protective measure.

Health and economic cost estimates of short-term total and wildfire PM2.5 exposure on work loss: using the consecutive California Health Interview Survey (CHIS) data 2015-2018

Instruction

To help determine the health protectiveness of government regulations and policies for air pollutant control for Americans, our study aimed to investigate the health and economic impacts of work loss due to sickness associated with daily all-source and wildfire-specific PM2.5 (particulate matter with an aerodynamic diameter smaller than 2.5 μm) exposures in California.

Methods

We linked the 2015-2018 California Health Interview Survey respondents' geocoded home addresses to daily PM2.5 estimated by satellites and atmospheric modelling simulations and wildfire-related PM2.5 from Community Multiscale Air Quality models. We calculated and applied the coefficient for the association between daily PM2.5 exposure and work loss from regression analyses to the Environmental Benefits Mapping and Analysis Program-Community Edition (BenMAP-CE) platform to assess the health and economic impacts of PM2.5 exposure on work loss due to sickness.

Results

We observed that each 1 µg/m3 increase in daily total PM2.5 exposure will lead to about 1 million days of work loss per year ranging from 1.1 to 1.6 million person-days, and the related economic loss was $310-390 million. Wildfire smoke alone could contribute to 0.7-2.6 million work-loss days with a related economic loss of $129-521 million per year in 2015-2018. Using the function coefficient in the current BenMAP, the excess work-loss days due to sickness was about 250 000 days and the estimated economic loss was about $45-50 million for each 1 µg/m3 increase in daily total PM2.5 exposure, and wildfire smoke alone would lead to 0.17-0.67 million work-loss days with related economic loss of $31-128 million per year during the same period.

Conclusions

Both conventional and wildfire-specific sources of PM2.5 produced substantial work loss and cost in California. Updating the current BenMAP-CE calculations for work-loss days will be essential in quantifying the current health impacts of PM2.5 to help inform the policies and regulations to protect public health.

Clearing the Air: Understanding the Impact of Wildfire Smoke on Asthma and COPD

Wildfires are a global natural phenomenon. In North America, wildfires have not only become more frequent, but also more severe and longer in duration, a trend ascribed to climate change combined with large fuel stores left from modern fire suppression. The intensification of wildfire activity has significant implications for planetary health and public health, as exposure to fine particulate matter (PM2.5) in wildfire smoke is linked to adverse health effects. This review focuses on respiratory morbidity from wildfire smoke exposure. Inhalation of wildfire PM2.5 causes lung injury via oxidative stress, local and systemic inflammation, airway epithelium compromise, and increased vulnerability to infection. Wildfire PM2.5 exposure results in exacerbations of pre-existing asthma and chronic obstructive pulmonary disease, with an escalation in healthcare utilization, including emergency department visits and hospitalizations. Wildfire smoke exposure may be associated with asthma onset, long-term impairment of lung function, and increased all-cause mortality. Children, older adults, occupationally-exposed groups, and possibly women are the most at risk from wildfire smoke. Future research is needed to clarify best practices for risk mitigation and wildfire management.