UC Merced

The San Joaquin Valley (SJV) of California has been consistently identified as having one of the highest levels of air pollution in the US. Despite federal and state standards, the SJV has been in non-attainment status for daily PM2.5 concentrations, extreme non-attainment for 8-hour O3 levels, and in attainment for NO2. Periods of pollution exposure are associated with increased health burden related to respiratory inflammation and undermined lung function, which aggravates respiratory diseases such as asthma and leads to symptoms such as coughing, wheezing, or difficulty breathing. Asthma costs US$ 82 billion annually in healthcare costs, missed work, and school in the U.S. Combining public health and economics methods, a comprehensive study of the epidemiological burden, monetized cost, cost-utility analysis, and policy options was conducted to one of the region’s most conspicuous and pervasive public health issue, air pollution. An epidemiological time-stratified case-crossover design was used to estimate the relationship between exposure to NO2, O3, PM2.5 and adverse health outcomes in asthma and upper respiratory infections (URIs). This study compared pollutant exposure effects for each case during limited time intervals and adjusting for seasonality. Employing a societal perspective, a prevalence approach burden of disease design was combined with environmental epidemiological methods to analyze the economic impact of O3, NO2, and PM2.5-related adverse health outcomes amongst SJV residents who attended the emergency room (ED) or were hospitalized in 2016. A cross-sectional online survey asked about self-protective behaviors, attitudes toward air pollution recommendations, air quality information knowledge, and mitigation behaviors, as well as whether their views are favorable or unfavorable. The EuroQOL-5D-3L instrument was utilized to assess differentials in health-related quality of life (HRQoL) distribution and favorability of policies. The study found that elevated concentrations of three criteria outdoor air pollutants are associated with increased asthma and URI-related ED visits and hospitalizations in SJV for all ages. NO2 exposure increased the odds of having an ED visit by 2.4% in lag 1 (95% CI: 1.017, 1.031). Lags 2, 3, 4, 5, 7, 9, and 14 were statistically significant. O3 modestly increased the odds of ED visits by 0.3% (95% CI:1.000, 1.006) after immediate exposure in the warm season. In the cold season, PM2.5 estimates were significant for all lags except for lags 4 and 12. The two-week lag increased the odds by 28% (95% CI:1.218, 1.345) for ED visits, and 16.5% (95% CI:1.009, 1.345) increased odds of being hospitalized after cumulative exposure to PM2.5. Asthma exacerbations monetized value ranged from US$ 3,353 to US$ 5,003 per ED visit, and for hospital admissions US$ 2,584 per inpatient day for adults 65 years and older to US$ 3,023 per child. The estimated value to society in healthcare costs, productivity losses, school absences, and opportunity costs from air pollution adverse health outcomes totaled US$ 498,014,124 in ED visits and US$ 223,552,720 in hospital admissions for the SJV population in 2016. The marginal reduction per one unit measure in the background concentrations of pollutants would avert 21,786 ED adverse events and

19,328 hospitalizations from the health burden on the SJV population. A total of 310 adult residents of the SJV participated in the survey. The mean age for the participants was 42.90 (+/- 16.84), and 34% reported having been diagnosed with asthma by a healthcare practitioner. People with asthma reported the lowest HRQoL with a health utility of U=0.747, with the lowest health utility reported by people with 4 or more chronic conditions that are sensitive to air pollution. Latent factors reported by SJV residents were concern for charge, expense, and car attributes for their interest in adopting electric vehicles. A differential interest in the involvement of local and not-local organizations in regulating air quality for the region. Also concern with what are the costs of air pollution and who pays for that cost of transforming practices. Nevertheless, SJV residents support air pollution control and preservation of public space. In terms of individual factors, residents report persistence of adverse symptoms due to poor air quality, and having to adopt personal actions to protect themselves, their children, and elders from air pollution. Socio-economic variables (age, sex, income) are significant predictors of those factors, and political views such as left-wing ideologies predicted favorability for policies that charge polluters to clean the air, control air pollution emissions, preserves public space, and interventions that reduce air pollution health symptoms and eases the burden on health. This study found that right wing ideology was a negative predictor for EV charge, EV car attributes and having local organizations intervening in air pollution emission control.This study provides new evidence about the effects of three criteria air pollutants and adverse health outcomes in the SJV region. Although, pollutant data from some rural population centers of the region were unavailable and that resulted in the exclusion of their residents’ ED visits and hospitalizations, these findings demonstrate that air pollution is a negative externality that imposes substantial social, environmental, and healthcare costs on the SJV. The air quality regulatory and public health governing bodies should consider revisions to regional pollutant thresholds and local public health strategies to prevent adverse health outcomes during short and prolonged periods of air pollution exposure, by doing this, the region would avert significant adverse health outcomes realizing economic savings of reducing air pollution in the region. In terms of adoption of air pollution control initiatives, these results could help public health, regulators and decision-makers, and communities understand the reasons for differential responses to mitigation efforts and help develop recommendations for improving air quality that are more likely to be supported by SJV residents.