Does socioeconomic and environmental burden affect vulnerability to extreme air pollution and heat? A case-crossover study of mortality in California.

BACKGROUND: Extreme heat and air pollution is associated with increased mortality. Recent evidence suggests the combined effects of both is greater than the effects of each individual exposure. Low neighborhood socioeconomic status ("socioeconomic burden") has also been associated with increased exposure and vulnerability to both heat and air pollution. We investigated if neighborhood socioeconomic burden or the combination of socioeconomic and environmental exposures ("socioenvironmental burden") modified the effect of combined exposure to extreme heat and particulate air pollution on mortality in California. METHODS: We used a time-stratified case-crossover design to assess the impact of daily exposure to extreme particulate matter <2.5 µm (PM2.5) and heat on cardiovascular, respiratory, and all-cause mortality in California 2014-2019. Daily average PM2.5 and maximum temperatures based on decedent's residential census tract were dichotomized as extreme or not. Census tract-level socioenvironmental and socioeconomic burden was assessed with the CalEnviroScreen (CES) score and a social deprivation index (SDI), and individual educational attainment was derived from death certificates. Conditional logistic regression was used to estimate associations of heat and PM2.5 with mortality with a product term used to evaluate effect measure modification. RESULTS: During the study period 1,514,292 all-cause deaths could be assigned residential exposures. Extreme heat and air pollution alone and combined were associated with increased mortality, matching prior reports. Decedents in census tracts with higher socioenvironmental and socioeconomic burden experienced more days with extreme PM2.5 exposure. However, we found no consistent effect measure modification by CES or SDI on combined or separate extreme heat and PM2.5 exposure on odds of total, cardiovascular or respiratory mortality. No effect measure modification was observed for individual education attainment. CONCLUSION: We did not find evidence that neighborhood socioenvironmental- or socioeconomic burden significantly influenced the individual or combined impact of extreme exposures to heat and PM2.5 on mortality in California. IMPACT: We investigated the effect measure modification by socioeconomic and socioenvironmental of the co-occurrence of heat and PM2.5, which adds support to the limited previous literature on effect measure modification by socioeconomic and socioenvironmental burden of heat alone and PM2.5 alone. We found no consistent effect measure modification by neighborhood socioenvironmental and socioeconomic burden or individual level SES of the mortality association with extreme heat and PM2.5 co-exposure. However, we did find increased number of days with extreme PM2.5 exposure in neighborhoods with high socioenvironmental and socioeconomic burden. We evaluated multiple area-level and an individual-level SES and socioenvironmental burden metrics, each estimating socioenvironmental factors differently, making our conclusion more robust.

Joint effects of traffic-related air pollution and hypertensive disorders of pregnancy on maternal postpartum depressive and anxiety symptoms.

BACKGROUND: Ambient air pollution has been linked to postpartum depression. However, few studies have investigated the effects of traffic-related NOx on postpartum depression and whether any pregnancy-related factors might increase susceptibility. OBJECTIVES: To evaluate the association between traffic-related NOx and postpartum depressive and anxiety symptoms, and effect modification by pregnancy-related hypertension. METHODS: This study included 453 predominantly low-income Hispanic/Latina women in the MADRES cohort. Daily traffic-related NOx concentrations by road class were estimated using the California LINE-source dispersion model (CALINE4) at participants' residential locations and averaged across pregnancy. Postpartum depressive and anxiety symptoms were evaluated by a validated questionnaire (Postpartum Distress Measure, PDM) at 1, 3, 6 and 12 months postpartum. Multivariate linear regressions were performed to estimate the associations at each timepoint. Interaction terms were added to the linear models to assess effect modification by hypertensive disorders of pregnancy (HDPs). Repeated measurement analyses were conducted by using mixed effect models. RESULTS: We found prenatal traffic-related NOx was associated with increased PDM scores. Specifically, mothers exposed to an IQR (0.22 ppb) increase in NOx from major roads had 3.78% (95% CI: 0.53-7.14%) and 5.27% (95% CI: 0.33-10.45%) significantly higher 3-month and 12-month PDM scores, respectively. Similarly, in repeated measurement analyses, higher NOx from major roads was associated with 3.06% (95% CI: 0.43-5.76%) significantly higher PDM scores across the first year postpartum. Effect modification by HDPs was observed: higher freeway/highway and total NOx among mothers with HDPs were associated with significantly higher PDM scores at 12 months postpartum compared to those without HDPs. IMPACT: This study shows that prenatal traffic-related air pollution was associated with postpartum depressive and anxiety symptoms. The study also found novel evidence of greater susceptibility among women with HDPs, which advances the understanding of the relationships between air pollution, maternal cardiometabolic health during pregnancy and postpartum mental health. Our study has potential implications for clinical intervention to mitigate the effects of traffic-related pollution on postpartum mental health disorders. The findings can also offer valuable insights into urban planning strategies concerning the implementation of emission control measures and the creation of green spaces.

Residents' experiences during a hydrogen sulfide crisis in Carson, California.

BACKGROUND: In early October 2021, thousands of residents in Carson, California began complaining of malodors and headaches. Hydrogen sulfide (H2S), a noxious odorous gas, was measured at concentrations up to 7000 parts per billion (ppb) and remained above California's acute air quality standard of 30 ppb for a month. Intermittent elevations of H2S continued for 3 months. After 2 months of malodor in this environmental justice community, a government agency attributed the H2S to environmental pollution from a warehouse fire. Research has yielded conflicting results on the health effects of H2S exposure at levels that were experienced during this event. This research fills a critical need for understanding how people perceive and experience emergent environmental health events and will help shape future responses. METHODS: Through a community-academic partnership, we conducted 6 focus groups with 33 participants who resided in the Carson area during the crisis. We sought to understand how this incident affected residents through facilitated discussion on topics including information acquisition, impressions of the emergency response, health symptoms, and ongoing impacts. RESULTS: The majority of participants were women (n = 25), identified as Latina/o (n = 19), and rent their homes (n = 21). Participants described difficulty obtaining coherent information about the emergency, which resulted in feelings of abandonment. Most participants felt that local government and healthcare providers downplayed and/or disregarded their concerns despite ongoing odors and health symptoms. Participants described experiencing stress from the odors' unknown health effects and continued fear of future odor incidents. Residents sought to take control of the crisis through information sharing, community networking, and activism. Participants experienced longer term effects from this event, including increased awareness of pollution and reduced trust in local agencies. DISCUSSION: This study demonstrates the necessity of clear, comprehensive, and prompt responses by relevant decisionmakers to chemical emergencies to appropriately address residents' fears, curb the spread of misinformation, and minimize adverse health effects. Participant responses also point to the benefit of supporting horizontal community networks for improved information sharing. By engaging directly with community members, researchers and disaster responders can better understand the various and complex impacts of chemical disasters and can improve response.

Cohort profile: The Assessing Imperial Valley Respiratory Health and the Environment (AIRE) study.

BACKGROUND: The Children's Assessing Imperial Valley Respiratory Health and the Environment (AIRE) study is a prospective cohort study of environmental influences on respiratory health in a rural, southeastern region of California (CA), which aims to longitudinally examine the contribution of a drying saline lake to adverse health impacts in children. OBJECTIVES: This cohort was established through a community-academic partnership with the goal of assessing the health effects of childhood exposures to wind-blown particulate matter (PM) and inform public health action. We hypothesize that local PM sources are related to poorer children's respiratory health. POPULATION: Elementary school children in Imperial Valley, CA. DESIGN: Prospective cohort study. METHODS: Between 2017 and 2019, we collected baseline information on 731 children, then follow-up assessments yearly or twice-yearly since 2019. Data have been collected on children's respiratory health, demographics, household characteristics, physical activity and lifestyle, via questionnaires completed by parents or primary caregivers. In-person measurements, conducted since 2019, repeatedly assessed lung function, height, weight and blood pressure. Exposure to air pollutants has been assessed by multiple methods and individually assigned to participants using residential and school addresses. Health data will be linked to ambient and local sources of PM, during and preceding the study period to understand how spatiotemporal trends in these environmental exposures may relate to respiratory health. PRELIMINARY RESULTS: Analyses of respiratory symptoms indicate a high prevalence of allergies, bronchitic symptoms and wheezing. Asthma diagnosis was reported in 24% of children at enrolment, which exceeds both CA state and US national prevalence estimates for children. CONCLUSIONS: The Children's AIRE cohort, while focused on the health impacts of the drying Salton Sea and air quality in Imperial Valley, is poised to elucidate the growing threat of drying saline lakes and wind-blown dust sources to respiratory health worldwide, as sources of wind-blown dust emerge in our changing climate.

Increased Risk of Gestational Hypertension by Periconceptional Exposure to Ambient Air Pollution and Effect Modification by Prenatal Depression.

BACKGROUND: Air pollution has been associated with gestational hypertension (GH) and preeclampsia, but susceptible windows of exposure and potential vulnerability by comorbidities, such as prenatal depression, remain unclear. METHODS: We ascertained GH and preeclampsia cases in a prospective pregnancy cohort in Los Angeles, CA. Daily levels of ambient particulate matters (with a diameter of ≤10 µm [PM10] or ≤2.5 µm [PM2.5]), nitrogen dioxide, and ozone were averaged for each week from 12 weeks preconception to 20 gestational weeks. We used distributed lag models to identify susceptible exposure windows, adjusting for potential confounders. Analyses were additionally stratified by probable prenatal depression to explore population vulnerability. RESULTS: Among 619 participants, 60 developed preeclampsia and 42 developed GH. We identified a susceptible window for exposure to PM2.5 from 1 week preconception to 11 weeks postconception: higher exposure (5 µg/m3) within this window was associated with an average of 8% (95% CI, 1%-15%) higher risk of GH. Among participants with probable prenatal depression (n=179; 32%), overlapping sensitive windows were observed for all pollutants from 8 weeks before to 10 weeks postconception with increased risk of GH (PM2.5, 16% [95% CI, 3%-31%]; PM10, 39% [95% CI, 13%-72%]; nitrogen dioxide, 65% [95% CI, 17%-134%]; and ozone, 45% [95% CI, 9%-93%]), while the associations were close to null among those without prenatal depression. Air pollutants were not associated with preeclampsia in any analyses. CONCLUSIONS: We identified periconception through early pregnancy as a susceptible window of air pollution exposure with an increased risk of GH. Prenatal depression increases vulnerability to air pollution exposure and GH.

The Role of Social Support and Acculturation Factors on Postpartum Mental Health Among Latinas in the MADRES Pregnancy Cohort.

We examined the associations between social support and postpartum mental health in 137 U.S. and foreign-born Latinas in the MADRES pregnancy cohort. We also examined whether language, years in the U.S., and country of birth moderates these relationships. Participants were administered PROMIS support measures 1 month postpartum; the Perceived Stress and Postpartum Distress Measure 3, 6, and 12 months postpartum; and the CESD scale 12 months postpartum. Perceived stress was lower at 6 months postpartum for women reporting higher emotional (p = 0.01), informational (p = 0.03), and instrumental support (p < 0.001); and lower at 12 months postpartum for women reporting higher emotional support (p = 0.01). Distress at 6 months was lower in women reporting higher emotional support (p = 0.03). Interactions suggest that associations were stronger for mothers that speak Spanish, spent fewer years in the U.S., and were born in Central America.

Respiratory and nervous system effects of a hydrogen sulfide crisis in Carson, California.

BACKGROUND: In October 2021, many residents in Carson, California experienced malodors, headaches, and respiratory symptoms. Hydrogen sulfide (H2S), a toxic odorous gas, was measured in Carson at concentrations up to 7000 parts per billion (ppb) and remained above California's acute air quality standard of 30 ppb for about a month. Research on how low- and medium-level H2S exposure affects the respiratory and nervous systems has yielded conflicting results, and few studies have examined the effects of subacute H2S exposure. METHODS: We calculated daily rates of emergency department (ED) visits with various respiratory and nervous systems diagnosis codes in Carson area ZIP codes (≤6 km from event's epicenter) and in Los Angeles County ZIP codes >15 km from event's epicenter (control area). Using controlled interrupted time series, we compared ED visit rates during the month of the H2S crisis in Carson to the predicted rates had the incident not occurred, based on 2018-2021 ED trends, and controlling for ED visit rate changes in the control area. RESULTS: We observed a 24 % increase in ED visit rate for all respiratory system diseases (rate ratio = 1.24, 95 % CI: 1.16, 1.32), a 38 % increase for asthma (RR = 1.38, 95 % CI: 1.26, 1.50), a 26 % increase for acute upper respiratory infections (RR = 1.26, 95 % CI: 1.13, 1.38), a 21 % increase for dizziness (RR = 1.21, 95 % CI: 1.04, 1.38), and a 25 % increase for migraines and headaches (RR = 1.25, 95 % CI: 1.13, 1.36) in the Carson area during the first month of the H2S event compared to the expected rates. CONCLUSIONS: This H2S crisis was associated with increased ED visit rates for multiple respiratory and nervous system outcomes. Reducing H2S exposure and improving to response during H2S episodes may improve public health.

Preconceptional and prenatal exposure to air pollutants and risk of gestational diabetes in the MADRES prospective pregnancy cohort study.

Background: Air pollution has been associated with gestational diabetes mellitus (GDM). We aim to investigate susceptible windows of air pollution exposure and factors determining population vulnerability. Methods: We ascertained GDM status in the prospective Maternal and Developmental Risks from Environmental and Social Stressors (MADRES) pregnancy cohort from Los Angeles, California, USA. We calculated the relative risk of GDM by exposure to ambient particulate matter (PM10; PM2.5), nitrogen dioxide (NO2), and ozone (O3) in each week from 12 weeks before to 24 weeks after conception, adjusting for potential confounders, with distributed lag models to identify susceptible exposure windows. We examined effect modification by prenatal depression, median-split pre-pregnancy BMI (ppBMI) and age. Findings: Sixty (9.7%) participants were diagnosed with GDM among 617 participants (mean age: 28.2 years, SD: 5.9; 78.6% Hispanic, 11.8% non-Hispanic Black). GDM risk increased with exposure to PM2.5, PM10, and NO2 in a periconceptional window ranging from 5 weeks before to 5 weeks after conception: interquartile-range increases in PM2.5, PM10, and NO2 during this window were associated with increased GDM risk by 5.7% (95% CI: 4.6-6.8), 8.9% (8.1-9.6), and 15.0% (13.9-16.2), respectively. These sensitive windows generally widened, with greater effects, among those with prenatal depression, with age ≥28 years, or with ppBMI ≥27.5 kg/m2, than their counterparts. Interpretation: Preconception and early-pregnancy are susceptible windows of air pollutants exposure that increased GDM risk. Prenatal depression, higher age, or higher ppBMI may increase one's vulnerability to air pollution-associated GDM risk. Funding: National Institutes of Health, Environmental Protection Agency.

Multiple chemical sensitivity scoping review protocol: overview of research and MCS construct.

INTRODUCTION: Multiple chemical sensitivity (MCS) has been characterised by reported adverse responses to environmental exposures of common chemical agents (eg, perfumes, paint, cleaning products and other inhaled or ingested agents) in low doses considered non-toxic for the general population. There is currently no consensus on whether MCS can be established as a distinct disorder. METHODS AND ANALYSIS: The scoping review of the literature will be guided by five questions: How is MCS defined and which diagnostic criteria have been proposed? What methods are used to report prevalence and incidence estimates of MCS? What are the characteristics of the body of scientific evidence that addresses whether MCS is a distinct disorder or syndrome? What underlying mechanisms for MCS have been proposed in the scientific literature? Which treatment and management approaches for MCS have been evaluated in empirical research studies? We will conduct a comprehensive search in 14 research databases. Citation screening will be supported by machine learning algorithms. Two independent reviewers will assess eligibility of full-text publications against prespecified criteria. Data abstraction will support concise evidence tables. A formal consultation exercise will elicit input regarding the review results and presentation. The existing research evidence will be documented in a user-friendly visualisation in the format of an evidence map. ETHICS AND DISSEMINATION: Determined to be exempt from review (UP-22-00516). Results will be disseminated through a journal manuscript and data will be publicly accessible through an online data repository. REGISTRATION DETAILS: The protocol is registered in Open Science Framework (osf.io/4a3wu).

Cardiovascular health and proximity to urban oil drilling in Los Angeles, California.

BACKGROUND: Although ~18 million people live within a mile from active oil and gas development (OGD) sites in the United States, epidemiological research on how OGD affects the health of nearby urban residents is sparse. Thousands of OGD sites are spread across Los Angeles (LA) County, California, home to the largest urban oil production in the country. Air pollution and noise from OGD may contribute to cardiovascular morbidity. OBJECTIVE: We examined the association between proximity to OGD and blood pressure in a diverse cohort of residents in LA. METHODS: We recruited residents in South LA who lived <1 km from an OGD site. We collected three blood pressure measurements for each participant and used the second and third measurements to calculate averages for systolic blood pressure (SBP) and diastolic blood pressure (DBP) separately. We conducted multivariable linear regression to examine the relationship between distance to OGD sites and continuous SBP and DBP, adjusting for BMI, smoking status, distance to freeway, sex, age, and use of antihypertension medications, with a random effect for household. We examined effect measure modification by BMI category and smoking category. RESULTS: Among the 623 adult participants, we found that for every 100 meter increase in distance from the OGD site, DBP was reduced by an average of 0.73 mmHg (95% CI: -1.26, -0.21) in this population. We observed stronger effects of proximity to OGD site on DBP among never smokers and among participants with a healthy BMI. The associations observed between proximity to OGD site and SBP were weaker but followed the same patterns as those for DBP. IMPACT: Our study suggests that living near urban oil drilling sites is significantly associated with greater diastolic blood pressure in urban Los Angeles communities. This research improves understanding of impacts from living nearby drilling operations on the health and welfare of this community, which is critical to inform public health relevant strategies.

Agricultural burning in Imperial Valley, California and respiratory symptoms in children: A cross-sectional, repeated measures analysis.

Burning of agricultural fields is an understudied source of air pollution in rural communities in the United States. Smoke from agricultural burning contains air toxics that adversely impact respiratory health. Imperial County in southeastern California is a highly productive agricultural valley that heavily employs agricultural burning to clear post-harvest crop remnants. We related individual-level exposure to agricultural burns to parent-reported respiratory symptoms in children. We leveraged the Children's Assessing Imperial Valley Respiratory Health and the Environment (AIRE) cohort of 735 predominantly Hispanic low-income elementary school students in Imperial County. Parents reported children's respiratory health symptoms and family demographic characteristics in questionnaires collected at enrollment and in annual follow-up assessments from 2017 to 2019. Permitted agricultural burns in Imperial County from 2016 to 2019 were spatially linked to children's geocoded residential addresses. We used generalized estimating equations to evaluate prevalence differences (PDs) in respiratory symptoms with increasing exposure to agricultural burning within 3 km in the 12 months prior to each assessment. Nearly half of children (346, 49 %) lived within 3 km of at least one agricultural burn in the year prior to study enrollment. In adjusted models, each additional day of agricultural burning in the prior year was associated with a one percentage point higher prevalence of wheezing (PD 1.1 %; 95 % CI 0.2 %, 2.0 %) and higher bronchitic symptoms (PD 1.0 %; 95 % CI -0.2 %, 2.1 %). Children exposed to four or more days of burning had an absolute increased prevalence of wheezing and bronchitic symptoms of 5.9 % (95 % CI -0.3 %, 12 %) and 5.6 % (95 % CI -1.8 %, 13 %), respectively, compared to no burn exposure. Associations with wheezing were stronger among children with asthma (PD 14 %; 95 % CI -1.4 %, 29 %). To our knowledge, this is the first U.S. study of agricultural burning and children's respiratory health. This work suggests that reducing agricultural burning could improve children's respiratory health.

Social and Environmental Stressors of Urban Oil and Gas Facilities in Los Angeles County, California, 2020.

Objectives. To examine patterns of cumulative environmental injustice with respect to operations of urban oil and gas development in Los Angeles County, California. Methods. Using CalEnviroScreen (CES) 4.0, oil and gas data permit records, and US census data, we examined the association between CES score (grouped into equal quintiles, with the lowest representing low cumulative burden) and oil and gas development (presence or absence of an oil and gas production well) within 1 kilometer of a census block centroid. Results. Among census blocks in the highest quintile of CES score, we observed 94% increased odds of being within 1 kilometer of a well compared with census blocks in the lowest quintile of CES score (odds ratio = 1.94; 95% confidence interval = 1.83, 2.10). In our multivariable model, the proportion of Black residents and higher quintiles of CES score were also associated with increased odds of a nearby oil and gas well. Conclusions. These findings suggest that oil and gas facilities are operating in neighborhoods already cumulatively burdened and with higher proportions of Black residents. (Am J Public Health. 2023;113(11):1182-1190. https://doi.org/10.2105/AJPH.2023.307360).

Adaptation Resources and Responses to Wildfire Smoke and Other Forms of Air Pollution in Low-Income Urban Settings: A Mixed-Methods Study.

Little is known about how low-income residents of urban communities engage their knowledge, attitudes, behaviors, and resources to mitigate the health impacts of wildfire smoke and other forms of air pollution. We interviewed 40 adults in Los Angeles, California, to explore their threat assessments of days of poor air quality, adaptation resources and behaviors, and the impacts of air pollution and wildfire smoke on physical and mental health. Participants resided in census tracts that were disproportionately burdened by air pollution and socioeconomic vulnerability. All participants reported experiencing days of poor air quality due primarily to wildfire smoke. Sixty percent received advanced warnings of days of poor air quality or routinely monitored air quality via cell phone apps or news broadcasts. Adaptation behaviors included remaining indoors, circulating indoor air, and wearing face masks when outdoors. Most (82.5%) of the participants reported some physical or mental health problem or symptom during days of poor air quality, but several indicated that symptom severity was mitigated by their adaptive behaviors. Although low-income residents perceive themselves to be at risk for the physical and mental health impacts of air pollution, they have also adapted to that risk with limited resources.

Ambient temperature and air pollution associations with suicide and homicide mortality in California: A statewide case-crossover study.

BACKGROUND: Higher ambient temperature and air pollution may contribute to increased risk of behaviors harmful to oneself or to others; however, quantitative evidence is limited. We examined the relationship of deaths due to suicide and homicide with temperature and air pollution in California-a state prone to high levels of both exposures. METHOD: California death certificates from 2014 to 2019 were used to identify deaths due to suicide and homicide. Residential data for decedents were used to assign exposure to daily temperature (maximum[Tmax], minimum[Tmin]) and daily average air pollution concentrations (particulate matter <10 µm[PM10] and < 2.5 µm[PM2.5], nitrogen dioxide[NO2], ozone[O3]). Tmin served as a surrogate for nighttime temperature. A time-stratified case-crossover study design using conditional logistic regression was used to assess the effects of daily exposure to temperature and air pollutants on suicide and homicide mortality, adjusting for relative humidity. Effect modification by sex and age was assessed. RESULTS: We observed 24,387 deaths due to suicide and 10,767 deaths due to homicide. We found a monotonic temperature association for both outcomes. A 5 °C increase in Tmax at lag-2 and Tmin at lag-0 was associated with 3.1 % (95 % confidence interval [CI]: 1.1 %-5.2 %) and 3.8 % (95%CI: 0.9 %-6.8 %) increased odds of death due to suicide, respectively. The increased odds of homicide mortality per 5 °C increase in Tmax at lag-0 and Tmin at lag-1 were 4.9 % (95%CI: 1.6 %-8.1 %) and 6.2 % (95%CI: 1.6 %-11.0 %), respectively. No air pollutant associations were statistically significant. Temperature associations were robust after adjustment for PM2.5. Some temperature effects were larger among women for suicide and men for homicide mortality, and among those over age 65 years for both outcomes. CONCLUSION: Risk of suicide and homicide mortality increases with increasing daily ambient temperatures. Findings have public health relevance given anticipated increases in temperatures due to global climate change.

California's early transition to electric vehicles: Observed health and air quality co-benefits.

The transition to electric vehicles is projected to have considerable public health co-benefits, but most evidence regarding air quality and health impacts comes from projections rather than real-world data. We evaluated whether population-level respiratory health and air quality co-benefits were already detectable at the relatively low levels of zero-emissions vehicles (ZEVs: battery electric, plug-in hybrid, hydrogen fuel cell vehicle) adoption in California, and evaluated the ZEV adoption gap in underserved communities. We conducted a zip code-level ecologic study relating changes in annual number of ZEVs (nZEV) per 1000 population from 2013 to 2019 to: (i) annual average monitored nitrogen dioxide (NO2) concentrations and (ii) annual age-adjusted asthma-related emergency department (ED) visit rates, while considering educational attainment. The average nZEV increased from 1.4 per 1000 population in 2013 (standard deviation [SD]: 2.1) to 14.7 per 1000 in 2019 (SD: 14.7). ZEV adoption was considerably slower in zip codes with lower educational attainment (p < 0.0001). A within-zip code increase of 20 ZEVs per 1000 was associated with a - 0.41 ppb change in annual average NO2 (95 % confidence interval [CI]:-1.12, 0.29) in an adjusted model. A within-zip code increase of 20 ZEVs per 1000 population was associated with a 3.2 % decrease in annual age-adjusted rate of asthma-related ED visits (95 % CI:-5.4, -0.9). Findings were supported by a variety of sensitivity analyses. Observational data on the early phase ZEV transition in California provided a natural experiment, enabling us to document the first real-world associations between increasing nZEV and changes in air quality and health. Results suggest co-benefits of the early-phase transition to ZEVs but with an adoption gap among populations with lower socioeconomic status which threatens the equitable distribution of possible co-benefits.

Perceptions and experiences of environmental health and risks among Latina mothers in urban Los Angeles, California, USA.

BACKGROUND: Environmental exposures during pregnancy and early childhood can have acute and chronic adverse health impacts. As minoritized populations are more likely to reside in areas with greater pollution, it is important to understand their views and lived experiences to inform action. The purpose of this community-driven qualitative research study was to understand how urban Latina mothers in Los Angeles County, California perceived environmental health and risks. METHODS: We conducted semi-structured individual interviews with Latina pregnant women and mothers of young children, recruited through existing collaborations with community organizations. Interviews conducted in either English or Spanish and were coded inductively according to a modified grounded theory approach. RESULTS: Thirty-six Latina mothers completed interviews between August-October 2016. Participants lived primarily in low-income communities of South-Central Los Angeles and East Los Angeles. We identified three major themes based on the participants' responses during interviews: Defining the Environment, Environment & Health Risks, and Social & Political Responsibility. Women defined their environment in terms of both "nature" and "hazards." They consistently identified foul odors, dirtiness, noise, trash, bugs, smoke, and other visible blights as indicators of household and neighborhood environmental hazards. They expressed fear and uncertainty about how their environment could affect their health and that of their children, as well as specific concerns about respiratory health, asthma, allergies, cancer, and adverse pregnancy outcomes. Mothers often changed individual behaviors around diet and cleaning during pregnancy but were frustrated by power imbalances that left them unable to change their home or neighborhood environments, despite their desire to do so. DISCUSSION: Our study is among the first to describe how urban Latina mothers perceive and experience environmental health risks during pregnancy and early childhood. Our research suggests additional attention is needed by public health professionals and researchers to address the environmental health risks that matter most to urban Latina mothers. They also highlight the tension that many urban Latina mothers feel between wanting to protect their families' health and well-being and feeling powerless to change their environment. Broad policy changes, rather than additional individual recommendations, are needed to address the concerns of this vulnerable population.

An applied environmental justice framework for exposure science.

On the 30th anniversary of the Principles of Environmental Justice established at the First National People of Color Environmental Leadership Summit in 1991 (Principles of Environmental Justice), we continue to call for these principles to be more widely adopted. We propose an environmental justice framework for exposure science to be implemented by all researchers. This framework should be the standard and not an afterthought or trend dismissed by those who believe that science should not be politicized. Most notably, this framework should be centered on the community it seeks to serve. Researchers should meet with community members and stakeholders to learn more about the community, involve them in the research process, collectively determine the environmental exposure issues of highest concern for the community, and develop sustainable interventions and implementation strategies to address them. Incorporating community "funds of knowledge" will also inform the study design by incorporating the knowledge about the issue that community members have based on their lived experiences. Institutional and funding agency funds should also be directed to supporting community needs both during the "active" research phase and at the conclusion of the research, such as mechanisms for dissemination, capacity building, and engagement with policymakers. This multidirectional framework for exposure science will increase the sustainability of the research and its impact for long-term success.

Residents' experiences during a hydrogen sulfide crisis in Carson, California.

Background: In early October 2021, thousands of residents in Carson, California began complaining of malodors and headaches. The odor was identified as hydrogen sulfide (H2S), a noxious odorous gas. H2S was measured at concentrations up to 7000 parts per billion (ppb) and remained above California's acute air quality standard of 30 ppb for a month, with intermittent elevations continuing for 3 months. After 2 months of malodor in this environmental justice community, the H2S was attributed to a warehouse fire. Research has yielded conflicting results on the health effects of H2S exposure at levels that were experienced during this event. There remains a gap in understanding how people perceive and experience odor emergencies such as this H2S event. Methods: Through a community-academic partnership, we conducted 6 focus groups in Carson with 33 participants who resided in the Carson area during the crisis. We sought to understand how this incident affected residents through facilitated discussion on topics including information acquisition, impressions of the emergency response, physical and mental health symptoms, and ongoing impacts. Results: The majority of participants were women (n = 25), identified as Latina/o (n = 19), and rent their homes (n = 21). Participants described difficulty obtaining coherent information about the emergency, which resulted in feelings of abandonment. Most participants felt that local government and health care providers downplayed and/or disregarded their concerns despite ongoing odors and health symptoms. Participants described experiencing stress from the odors' unknown health effects and continued fear of future odor incidents. Residents sought to take control of the crisis through information sharing, community networking, and activism. Participants experienced longer term effects from this event, including increased awareness of pollution and reduced trust in local agencies. Discussion: This study demonstrates the necessity of clear, comprehensive, and prompt responses by relevant decisionmakers to chemical emergencies to appropriately address residents' fears, curb the spread of misinformation, and minimize adverse health effects. Participant responses also point to the benefit of supporting horizontal community networks for improved information sharing. By engaging directly with community members, researchers and disaster responders can better understand the various and complex impacts of chemical disasters and can improve response.