Research Grants Program Office

Do electric vehicles (EVs), and the expansion of curbside charging infrastructure in particular, undermine efforts to reduce vehicle travel? As EVs gain market share, decisionmakers may be less inclined to support policies such as bicycle lanes and reduced parking if they compete for space with EV chargers. We find no evidence, however, of policy substitution. Surveys in Los Angeles indicate that public support for policies to reduce driving is not swayed by the availability of EV charging. Furthermore, interviews in North American cities reveal that local officials are cautious about locking in scarce curbspace for EVs, and universally prioritized curb uses such as bicycle and bus lanes, street trees, and parklets. In our sample of early adopter cities, EV charging is not currently diminishing the political will for policies to reduce driving. However, this caution has slowed the rollout of curbside charging in North America.

Objective The number of missed school days attributable to secondhand smoke (SHS) exposure at home among U.S. children has not been quantified. We estimated the association between SHS exposure at home and school absenteeism and derived national estimates of SHS-attributable missed school days. Methods We analyzed data from the 2016–2024 National Survey of Children's Health for U.S. children aged 6–11 years. Propensity score weighting and two-part models were used to estimate the association between SHS exposure at home and school absenteeism. National estimates of SHS-attributable missed school days were derived by combining model-based attributable fractions with national public school enrollment data. Results SHS exposure at home was associated with both a higher likelihood of missing school and a greater number of missed school days among children with any absence. In 2024, an estimated 266,008 (95% CI: 139,627, 392,390) missed school days were attributable to SHS exposure at home nationwide, corresponding to 0.95 additional missed school days per exposed child (95% CI: 0.56, 1.34). Conclusions This study provides the first national estimates of SHS-attributable missed school days among U.S. children. These findings suggest that reducing children's SHS exposure may further improve school attendance and promote more efficient use of educational resources.

BACKGROUND: Safe passage interventions aim to enhance public safety and improve access to community resources, including public parks, in underserved communities. However, no studies have directly compared community- and police-led safety interventions with respect to park-based moderate to vigorous physical activity (MVPA). To address this gap, we compared associations between Community-led Safe Passage Services (SPS) and the Los Angeles Police Department Community Safety Partnership (CSP) program with MVPA in South Los Angeles public parks. METHODS: We conducted structured observations of 3997 park users across 8 SPS and 9 CSP parks in South Los Angeles using the System for Observing Play and Recreation in Communities and the Physical Activity Resource Assessment. We applied t tests, analysis of variance, and hierarchical linear models to examine MVPA across park intervention types. RESULTS: Overall, MVPA was higher in SPS parks (P < .001). Black, male, teen, and adult park users exhibited significantly higher MVPA in SPS parks (P < .001). A hierarchical linear model controlling for sex, age, race, and park conditions indicated that Black park users were significantly less physically active in CSP parks (P = .05). Conversely, Black park users had significantly higher MVPA in SPS parks (P = .034). Intervention type was a stronger predictor of MVPA than park features and amenities, whereas incivilities were negatively associated with MVPA (P < .001). CONCLUSIONS: Community-led safety interventions may promote physical activity among Black park users. These findings suggest that community-led public park safety models are a promising approach for advancing health equity.

BackgroundVeterans have a unique health profile and risk for substance use, but few studies compare cannabis use patterns among US military Veterans and non-veteran civilians.ObjectiveTo examine differences in age-specific patterns, modes of use, and sociodemographic correlates of cannabis use between Veterans and non-Veterans.Design, Participants, MeasuresWe conducted a cross-sectional analysis of Behavioral Risk Factor Surveillance System data from 2016 to 2023. The analytic sample included 907,136 adults aged 18 to 80 years with complete data on self-reported veteran status and cannabis use. Primary outcomes were past 30-day cannabis use (yes/no), frequency of use in the past 30 days, and inhalational vs. non-inhalational use methods. Multivariable logistic regressions were used to assess sociodemographic and behavioral correlates of cannabis use. Analyses were conducted from March to June 2025.ResultsAmong participants, 114,193 (12.6%) were Veterans. Although overall cannabis use was lower among Veterans than non-Veterans, age-specific patterns differed. Veterans aged 50–64 years were 43% (95% CI, 28–59%) more likely to report cannabis use than non-Veterans, and those aged 65–80 were 22% (95% CI, 9–37%) more likely. Older Veterans also reported more frequent cannabis use in the past 30 days (mean 18.4 versus 15.8 days among those aged 50–64 years; 17.3 vs. 14.5 days among those aged 65–80 years). Inhalational use was more common among Veterans than non-Veterans (90.0%; 95% CI, 87.8–91.9% vs. 83.7%; 95% CI, 82.5–84.9%). Some correlates of cannabis use were shared across groups; however, educational attainment was differentially associated with cannabis use by veteran status.ConclusionsVeterans aged ≥ 50 years were more likely to report cannabis use and used it more frequently than their non-veteran peers, suggesting they may need tailored interventions to address cannabis use.

INTRODUCTION: Little is known whether cannabis and tobacco use are indicators of suicide-related risks. This longitudinal study examined the associations of cannabis and tobacco use with risks of suicide attempt/death and overdose death over a 2-year follow-up in a cohort of veterans prescribed opioids. METHODS: This study analyzed data in 2024 using a national cohort of 923,291 veterans receiving opioid analgesics in Veterans Health Administration clinics collected during 2014-2019. Cannabis and tobacco use were assessed at cohort entry. Outcomes (suicide attempts, suicide death, overdose death) were obtained at follow-up through 2021. Cause-specific hazard models were used to examine the associations of cannabis and tobacco use with each outcome, adjusting for well-established risk factors for suicide/overdose (e.g., substance use disorders, mental health, sociodemographics). RESULTS: At baseline, 5.4% of the cohort used cannabis, and 39.4% used tobacco. At the end of follow-up (median follow-up time of 6.7-6.8 years), 2.2% of the sample had attempted suicide, 0.4% had died by suicide, and 0.5% had died by overdose. In adjusted models, cannabis use was associated with a higher rate of suicide attempt (hazard ratio=1.11, 95% CI=1.06, 1.15). Current use of tobacco at baseline (versus never use) was associated with a higher rate of suicide attempts (hazard ratio=1.18, 95% CI=1.13, 1.22), suicide deaths (hazard ratio=1.19, 95% CI=1.07, 1.32), and overdose deaths (hazard ratio=1.67, 95% CI=1.51, 1.83). CONCLUSIONS: Cannabis and tobacco use were associated with suicide attempts/deaths and overdose deaths among veterans prescribed opioid analgesics, underscoring a need for monitoring patients who use tobacco and cannabis in this population.

BACKGROUND: Farmworkers in the United States are exposed to extreme heat and demanding physical labor, placing them at increased risk for heat-related illnesses (HRI). This study examined individual, occupational, and household factors associated with self-reported HRI among men and women farmworkers in Imperial Valley, California. METHODS: This cross-sectional study used a convenience and snowball sampling approach to recruit agricultural workers through a local community organization. Participants were administered an in-person interview on their experience with HRI and potential risk factors. A multivariate regression analysis was conducted to identify variables related to HRI. RESULTS: From 300 participants, 119 (39.7%) experienced HRI, defined as reporting at least three HRI symptoms. In the multivariate regression analysis, HRI odds were significantly increased in women (aOR: 2.36, 95%CI: 1.35-4.15), in those reporting heat-related sleep problems (aOR: 3.25, 95%CI: 1.50-7.02), face covering use (aOR: 1.94, 95%CI: 1.09-3.45) and those working more than 5 days per week (aOR: 2.19, 95%CI: 1.23-3.91). Older age had a modest association with lower odds of HRI (aOR: 0.98, 95%CI: 0.96-0.99) and more than one break per day (aOR: 0.59, 95%CI: 0.35-1.00, p = 0.053) was associated with marginally lower HRI odds. CONCLUSIONS: As climate change continues to intensify occupational heat exposure among agricultural workers, interventions should extend beyond purely workplace-focused efforts and address cumulative exposure, non-occupational factors and structural constraints. Report of heat-related sleep problems has been associated with HRI relatively recently. Future research should establish the occupational, structural, and biological pathways contributing to the increased HRI odds for women farmworkers.

OBJECTIVE: Nicotine and cannabis vaping are increasingly prevalent among young adults, and aiding sleep is a common reason for cannabis use. This study examined relationships between daily nicotine/cannabis vaping patterns and sleep. METHODS: From 2023 to 2024, 111 California young adults (aged 18-29; mean age = 23.9±3.0; 64% female; 31.5% non-Hispanic White) who vaped nicotine/cannabis ≥20 days/month completed 30 consecutive days of smartphone-based surveys. Self-reported sleep outcomes included 1) sleep duration (inadequate <7 versus adequate ≥7 hours) and 2) sleep quality (0=terrible to 10=excellent). Daily vaping patterns were non-vaping, nicotine-only vaping, cannabis-only vaping, or same-day co-vaping. Generalized mixed-effects models examined day-level associations between vaping patterns and sleep that night, adjusting for other substance use and baseline covariates. RESULTS: Of 2147 daily assessments, 51.7% reported inadequate sleep; mean sleep quality was 6.1±2.1. Nicotine-only vaping was most frequently reported (42.5% of the days), followed by same-day co-vaping (32.1%), non-vaping (16.1%), and cannabis-only vaping (9.3%). Nicotine-only vaping days had greater odds of inadequate sleep versus non-vaping (OR=1.40, 95%CI: 1.01-1.94) and versus cannabis-only days (1.93 [1.31-2.85]). Days with same-day co-vaping had greater odds of inadequate sleep compared with cannabis-only vaping (1.50 [1.01-2.23]). Associations between sleep quality and daily vaping patterns were not statistically significant. CONCLUSIONS: Nicotine vaping was associated with inadequate sleep duration compared to non-vaping or cannabis-only vaping. Despite perceptions of cannabis as a sleep aid, cannabis vaping did not improve sleep quality compared to non-vaping. These findings highlight the need for educational efforts or interventions addressing sleep health among young adults who vape nicotine and/or cannabis.

INTRODUCTION: State and local jurisdictions in the United States are increasingly adopting flavored tobacco sales restrictions (FTSRs) to mitigate tobacco initiation and use. Policy implementation is highly understudied yet can impact policy effectiveness. This review examines existing literature on state and local FTSR policy design and implementation in the United States. METHODS: We systematically searched for PubMed articles published by December 31, 2024 which were: original research articles in English focused on a US state or local FTSR that reported at least one policy implementation outcome measure. We excluded articles that were systematic reviews or reported on federal or non-FTSR policy. Guided by policy and implementation science frameworks, we developed a data extraction template to report: policy design elements, study characteristics, and implementation measures (ie, inputs, activities, outcomes). RESULTS: Of 1595 articles identified, 30 were retained for review. Most evaluated local FTSRs, and eight evaluated a statewide policy. Pre-post test and cross-sectional study designs were the most common. Frequently reported implementation outcomes were acceptability, appropriateness, feasibility, and fidelity/compliance. Studies with pre-post test designs and comparison groups showed significantly increased fidelity/compliance (ie, reduced availability of restricted products) in FTSR jurisdictions. A majority (56.7%) detailed an implementation input for infrastructure (eg, resources) or activity (eg, outreach). Few described enforcement-related mechanisms. CONCLUSIONS: Key gaps exist in policy implementation articles on state and local FTSRs in the United States, including infrequent reporting of enforcement agencies and penalties which may impact implementation. Additional mixed-methods research is needed to compare FTSR implementation across jurisdictions with varying policy designs. IMPLICATIONS: Results contribute to our understanding of FTSR policy design, evaluation, and areas needed for intervention to strengthen implementation. Strategies to support compliance include guidance and criteria to identify targeted products for retailers and enforcement agents. Research gaps include a lack of information on penalty structures and data from enforcement agents or on violations, which are missed opportunities to evaluate components that can impact implementation and effectiveness.

Farmworkers are particularly vulnerable to heat stress, which can escalate into heat-related illnesses such as heat exhaustion or heat stroke, and can also impact productivity loss. Heat exposure varies considerably depending on season, work-shift timing, acclimatization, and workload. We examine the frequency of heat stress exceedance in the Imperial and Coachella Valleys of southern California using wet bulb globe temperature (WBGT) calculated using the outputs from Weather Research and Forecasting (WRF) model for a reference year of 2020. The critical WBGT threshold of 80℉ is exceeded for more than 500 hr in August, with considerable exceedance in all key harvesting months of April, May, and June. The threshold is exceeded most frequently in August, with daytime (nighttime) exceedance of 96.3% (38.0%) in the Imperial and 72.5% (11.9%) in the Coachella Valleys. Occupational WBGT limits are also exceeded in most crop environments for unacclimatized workers, and even for acclimatized workers during date and sugarcane harvests. Adjusting the work schedule to an early morning or late evening shift can reduce workers' productivity loss by up to 40%. Based on our findings, we propose several strategies to mitigate heat risks among farmworkers: (a) adjusting work hours to include cooler morning or evening hours (b) using WBGT instead of air temperature to monitor heat exposure (c) adopting variable rest-break schedules (d) reducing nighttime heat exposure during summer to allow recovery from daytime heat (e) taking extra precaution in high-risk crop zones (f) avoiding nighttime irrigation during summer, and (g) revising thresholds and definitions used to identify heatwaves.