Berkeley Public Health Division

Consumer-grade natural gas leaks contribute to methane-induced climate change and can degrade air quality. However, limited leakage and gas composition data exist outside of North America. Here, we measured stove-off gas leakage in 35 homes and chemically characterized 78 unburned gas samples from residential stoves across seven cities in the United Kingdom, Netherlands, and Italy. On average, benzene in unburned gas was substantially elevated compared to North America (9 to 73 times higher), while sulfur-based odorants were lower. Modeling of indoor and outdoor benzene enhancements from gas leaks showed potential for hazardous benzene exposure, often undetectable by odor. Three of 35 homes exhibited a stove-off leak that, combined with city-median benzene in gas, resulted in modeled benzene enhancements above the European Union's annual limit value (1.6 ppbv). The combination of high benzene and relatively low odorization in natural gas suggests that hazardous leaks are likely underreported in Europe.

Background:Interleukin-6 (IL-6) is a cytokine that plays a key role in systemic hyperinflammation and may mediate the relationship between acute COVID-19 and severe long-term outcomes such as Long COVID or death. IL-6 modulating drugs may reduce patients’ risk of severe post-COVID-19 outcomes.Methods:We conducted an emulated target trial in a retrospective cohort of patients with moderate-to-severe rheumatoid arthritis who were prescribed IL-6 receptor antagonists (sarilumab or tocilizumab, pooled treatment) or other biologic agents (anakinra or baricitinib, pooled comparator) in 2022. We compared the 12–month cumulative incidence of mortality and Long COVID (diagnosed and probable) between groups using Super Learner and targeted maximum likelihood estimation, adjusting for covariates of interest.Results:In our cohort of 3,553 patients, we found that prescription of IL-6 receptor antagonists was associated with a lower 12-month cumulative mortality (adjusted relative risk (aRR) 0.40, 95% CI 0.27, 0.59), diagnosed Long COVID aRR 0.42, 95% CI 0.23, 0.78), and probable Long COVID (aRR 0.71, 95% CI 0.61, 0.83), compared to prescription of other biologic agents, among rheumatoid arthritis patients.Conclusions:IL-6 receptor antagonists may prevent the incidence of severe post-COVID-19 outcomes, such as Long COVID or mortality. This supports the hypothesis that IL-6 may be a mechanistic biomarker of COVID-19 sequelae and that acute COVID-19 severity may mediate this relationship.

Population dynamics play a pivotal role in development, exacerbating social, economic and environmental challenges. Yet, this factor remains largely understudied in undergraduate curricula in the United States. This study explores the perceptions of University of California (UC) faculty of the concept of population dynamics and its integration into their teaching. Through a mixed-methods approach, it investigates the meanings that faculty associate with this concept, the importance they attribute to it, and the barriers they face in teaching it. Findings reveal that UC faculty across multiple disciplines believe that understanding this topic is essential for college students’ future careers. However, study participants reported that population dynamics were infrequently integrated into undergraduate courses due to their interdisciplinary nature, lack of faculty training in demography and lack of prioritisation by the UC system. Other barriers to teaching this topic include the sensitive nature of associated themes like migration, family planning and gender norms. Our findings suggest that the teaching of this subject, as well as its integration into the curriculum, lacks a systematic and coordinated approach. Its inclusion (or lack thereof) depends largely on individual faculty’s preferences and their level of demographic expertise. The gap between its perceived importance and its representation in the curriculum highlights the need for universities to make a more consistent effort to support faculty in integrating this topic in meaningful ways. Adequate coverage of population dynamics within institutions of higher education will help students to increase awareness and contribute to efforts to address global demographic challenges.

Research on the health impacts of segregation in nonresidential spaces, such as the workplace, is limited. Racial discrimination in the work environment can hinder career advancement (job mobility) and exacerbate socioeconomic risk factors of cardiovascular disease (CVD). Using a cohort of manufacturing workers in Detroit, we assessed the relationship between Black-White workplace racial segregation and CVD mortality risk. We considered job mobility as a potential modifier among Black workers from the United Autoworkers-General Motors cohort. This retrospective cohort study included 5047 Black workers employed for at least 3 years, with follow-up from 1941 to 2015. Annual segregation exposure was cumulated over working life and divided by time since hire. Job mobility was calculated using each worker's time-varying cumulative area under the curve of their movement between lower and higher-wage jobs. Cox models estimated the impact of segregation and job mobility on CVD mortality. We fit penalized splines to examine the shape of the relationship between segregation and CVD mortality. The average exposure to racial segregation was 13%. We observed a strong positive association between greater workplace racial segregation and CVD mortality, with a hazard ratio of 1.61 (95% CI, 1.18-2.19) in the highest exposure category compared with the lowest. Among workers with lower job mobility, those with moderate or high segregation exposure had increased CVD risk compared with those with low segregation exposure (moderate hazard ratio, 2.13 [95% CI, 1.63-2.78]; high hazard ratio, 2.04 [95% CI, 1.27-3.28]). Results among Black workers with higher job mobility were similar. Our findings provide evidence that increasing workplace Black-White segregation may increase CVD mortality among Black workers. We observed that the cardiovascular harm of racial segregation to Black workers operates in the workplace regardless of job mobility to positions with higher wages.

Petroleum refineries are significant sources of toxic contaminant emissions globally that threaten the health of refinery workers and nearby populations. We conducted a scoping review of the epidemiological evidence concerning acute and chronic health impacts of petroleum and biofuel refineries on surrounding communities. We evaluated the evidence using risk-of-bias assessments and catalogued findings into an evidence map to identify gaps in the literature. We systematically searched studies published by August 2024 on PubMed, Embase, and Web of Science. Our review includes 54 studies published between 1977 and 2024 in 15 international regions. Most studies focused on cancer, respiratory effects, biomarkers of effect, acute symptoms, and cardiovascular effects; fewer studies examined other chronic diseases, reproductive or birth outcomes. Multiple studies find evidence that residential proximity to refineries is associated with higher risks of leukemia, asthma, bronchitis, respiratory symptoms, and healthcare utilization. 13 studies found evidence of dose-response relationships between proximity or duration of residence near a refinery and severity of risk. Common study limitations included imprecise exposure measures, limited control for confounding, and cross-sectional designs. Recent developments have improved causal inferences, including air pollutant dispersion modeling, quasi-experimental designs, and individual-level exposure measures. The literature suggests a range of acute and chronic health effects among adults and children living near refineries. Additional longitudinal studies and studies of biorefineries are needed, especially as the energy transition from petroleum to bio-based transportation fuels accelerates. Our review underscores the need for additional measures to protect the health of refinery communities.

Medicaid serves over 70 million Americans, yet barriers to consistent, high-quality care endure due to workforce shortages, fragmented service delivery, and administrative burden. Artificial intelligence (AI) offers not just operational efficiency but the potential to transform the Medicaid care experience. AI-powered digital assistants can deliver 24/7 multilingual voice or text support, expanding access to personalized, emotionally-intelligent assistance. Under existing workforce supervision, these agents can bridge critical gaps in behavioral health and community coordination through tools like therapy chatbots that reduce loneliness and improve engagement. As “embedded staff” in provider offices and community organizations, digital assistants can create a unified infrastructure for whole-person care. We introduce the concept of Precision Benefits: delivering the right support to the right person at the right time to prevent avoidable health and social deterioration. This aligns with administrative and eligibility reforms in H.R.1, which require states to improve efficiency and verification while fostering innovation and preserving state authority over AI regulation. Realizing this vision demands responsible AI development – addressing safety, bias, privacy, and trust – and modernization of infrastructure and payment models. Yet the opportunity is clear: AI can power a smarter and more equitable Medicaid system, one that puts everyone on an upward life trajectory.

Sea level rise (SLR) increases the risk of flooding at coastal sites that use and produce hazardous substances. We assess whether socially marginalized populations in the United States are more likely to be impacted by projected SLR-related flooding of hazardous sites that could result in contaminant releases. We identify 5500 facilities at risk of a 1-in-100-year flood event by 2100 under a scenario of continued high greenhouse gas emissions, including coastal power plants, sewage treatment facilities, fossil fuel infrastructure, industrial facilities, and formerly used defense sites. Seven states (Louisiana, Florida, New Jersey, Texas, California, New York, and Massachusetts) account for nearly 80% of projected at-risk facilities. Controlling for population density and county, a one standard deviation increase in the proportion of linguistically isolated households, neighborhood residents identifying as Hispanic, households with incomes below twice the federal poverty line, households without a vehicle, non-voters, and renters is associated with 19-41% higher likelihood of having a site at risk of SLR-related flooding within 1 kilometer (odds ratios [95% confidence intervals]: 1.19 [1.09, 1.31], 1.22 [1.08, 1.37], 1.27 [1.16, 1.39], 1.35 [1.21-1.51], 1.36 [1.21, 1.53], and 1.41 [1.32, 1.52], respectively). Results elucidate the need for disaster planning, land-use decision-making, as well as mitigation strategies that address the inequitable hazards and potential health threats posed by SLR.