Drought is one of the most widespread and disruptive natural hazards globally, with environmental and societal effects that may increase psychological distress. Yet, its association with suicide in the U.S. remains understudied. We examined the relationship between drought and suicide mortality across the contiguous U.S. Drought severity was measured using the Evaporative Demand Drought Index, and suicide data from the National Center for Health Statistics. We used Generalized Additive Models (GAMs) to estimate incidence rate ratios (IRRs) and absolute risk differences (ARDs), with 95% confidence intervals. Analyses were stratified by age, sex, and urbanicity. From 2000 to 2018, the U.S. recorded 350,434 firearm-related and 323,225 non-firearm suicide deaths. Drought affected 37.4% of county-months, and both suicide types were positively associated with drought-especially under severe conditions. For firearm suicides, worsening drought was linked to an IRR of 1.109 (95% CI: 1.091-1.128) and ARD of 0.704 (95% CI: 0.595-0.811); improving drought had an IRR of 1.094 (95% CI: 1.076-1.112) and ARD of 0.608 (95% CI: 0.501-0.715). For non-firearm suicides, worsening drought was associated with an IRR of 1.057 (95% CI: 1.037-1.077) and ARD of 0.347 (95% CI: 0.232-0.461), while improving drought had an IRR of 1.073 (95% CI: 1.054-1.093) and ARD of 0.456 (95% CI: 0.344-0.568). Severe drought was significantly linked to higher suicide mortality, especially firearm-related deaths among older adults, women, and those in non-metro areas. Findings highlight the need to integrate mental health support into drought preparedness for vulnerable populations. Hosted file AGU_Manuscript_Abadi_June24th_2025.docx available at https://authorea.com/users/933540/ articles/1311569-the-lethal-connection-investigating-the-relationship-of-drought-conditions-on-firearm-and-nonfirearm-suicides-among-us adults Hosted file AGU_SuppInfo_Abadi_June24_2025.docx available at https://authorea.com/users/933540/articles/ 1311569-the-lethal-connection-investigating-the-relationship-of-drought-conditions-on-firearm-and-nonfirearm-suicides-among-us adults 1 20 Key Points: 21 • Firearm and nonfirearm suicides in the U.S. increase during all drought phases, 22 especially during severe drought conditions. 23 • The strongest associations were observed among older adults, women, and rural 24 populations. 25 • Drought-related suicide risk underscores the need for mental health integration into 26 early warning and mitigation efforts. 27 Abstract 28 Drought is one of the most widespread and disruptive natural hazards globally, with 29 environmental and societal effects that may increase psychological distress. Yet, its association 30 with suicide in the U.S. remains understudied. We examined the relationship between drought 31 and suicide mortality across the contiguous U.S. Drought severity was measured using the 32 Evaporative Demand Drought Index, and suicide data from the National Center for Health 33 Statistics. We used Generalized Additive Models (GAMs) to estimate incidence rate ratios (IRRs) 34 and absolute risk differences (ARDs), with 95% confidence intervals. Analyses were stratified by 35 age, sex, and urbanicity. From 2000 to 2018, the U.S. recorded 350,434 firearm-related and 36 323,225 non-firearm suicide deaths. Drought affected 37.4% of county-months, and both 37 suicide types were positively associated with drought-especially under severe conditions. For 38 firearm suicides, worsening drought was linked to an IRR of 1.109 (95% CI: 1.091-1.128) and 39 ARD of 0.704 (95% CI: 0.595-0.811); improving drought had an IRR of 1.094 (95% CI: 1.076-40 1.112) and ARD of 0.608 (95% CI: 0.501-0.715). For non-firearm suicides, worsening drought 41 was associated with an IRR of 1.057 (95% CI: 1.037-1.077) and ARD of 0.347 (95% CI: 0.232-42 0.461), while improving drought had an IRR of 1.073 (95% CI: 1.054-1.093) and ARD of 0.456 43 (95% CI: 0.344-0.568). Severe drought was significantly linked to higher suicide mortality, 44 especially firearm-related deaths among older adults, women, and those in non-metro areas. 45 Findings highlight the need to integrate mental health support into drought preparedness for 46 vulnerable populations. 47 48 Plain Language Summary 49 This study explores how drought, a prolonged period of unusually dry weather, affects suicide 50 rates in the United States. Using data from all counties between 2000 and 2018, we analyzed 51 over 670,000 deaths by suicide to determine if dry conditions were linked to higher risk. We 52 found that both firearm and nonfirearm suicides increased during all stages of drought, with 53 the highest risk seen during the most severe drought periods. Certain groups-including older 54 adults, women, and people living in rural areas-were more affected. The risk was especially 55 high for suicides involving firearms. These findings suggest that dry weather may create or 56 worsen stress, especially for people who are already vulnerable. By better understanding when 57 and where these risks increase, we can improve public health strategies. Adding mental health 58 support to drought preparation and response plans could help save lives, particularly in rural 59 communities and during times of severe environmental stress. 60 61

Purpose of Review: Drought is one of the most far-reaching natural disasters, yet drought and health research is sparse. This may be attributed to the challenge of quantifying drought exposure, something complicated by multiple drought indices without any designed for health research. The purpose of this general review is to evaluate current drought and health literature and highlight challenges or scientific considerations when performing drought exposure and health assessments. Recent Findings: The literature revealed a small, but growing, number of drought and health studies primarily emphasizing Australian, western European, and US populations. The selection of drought indices and definitions of drought are inconsistent. Rural and agricultural populations have been identified as vulnerable cohorts, particularly for mental health outcomes. Summary: Using relevant examples, we discuss the importance of characterizing drought and explore why health outcomes, populations of interest, and compound environmental hazards are crucial considerations for drought and health assessments. As climate and health research is prioritized, we propose guidance for investigators performing drought-focused analyses.

Individual and social characteristics are attributed to violent behavior in schools, yet environmental hazards may play an understudied role. Ambient air pollution has been linked to neurological dysfunction that inhibits decision-making and may result in violent behavior in adult populations. However, little is known on how air pollution may be associated with violent behaviors in children. A cross-sectional ecologic study was designed to estimate the associations between air pollution (fine particulate matter, carbon monoxide, and nitrogen dioxide) with the occurrence of violent incidents and incidents involving a weapon among a cohort of children in Minnesota schools (2008–2012). Differences by urban and rural status of schools were also explored. Negative binomial regression models were developed to estimate incidence rate ratios (IRR) and incidence rate differences (IRD) to describe associations between air pollution and violent incidents in school settings. Our results indicate that the highest levels of carbon monoxide, nitrogen dioxide and fine particulate matter concentrations were associated with increased violent disciplinary incidents. Among the total student population, the 4th quartile of carbon monoxide exposure was associated with an IRD of 775.62 (95% CI 543.2, 1008.05) violent incidents per 100,000 students per school year compared to schools in the lowest quartile of exposure. Comparing the 4th to the 1st quartiles of exposure, nitrogen dioxide and fine particulate matter had an IRD of 629.16 (95% CI 384.87, 873.46), and 510.49 (95% CI 274.92, 746.05) violent incidents per 100,000 students per school year respectively. Schools in urban settings shared a larger burden of violent incidents associated with air pollution compared to rural schools. Modifying environmental pollutants surrounding school environments, particularly for high exposure communities, may be a novel tool for reducing violence and subsequent injuries in schools.

BACKGROUND AND AIM[|]BACKGROUND: Drought is a significant weather event that impacts more individuals globally than any other natural calamity. It can disrupt ecosystems and lead to mental stress. ...

BACKGROUND AND AIM[|]To prevent electrical equipment from igniting wildfires, utility companies in California are authorized to de-energize, or turn off power to their lines in events called Public...

BACKGROUND AND AIM[|]To prevent electrical equipment from igniting wildfires, utility companies in California are authorized to de-energize, or turn off power to their lines in events called Public...

The link between air pollution exposure and increased mortality and morbidity is firmly supported by a broad evidence base. The 2015 Global Burden of Diseases Study, a 195-country investigation, found fine particulate matter (ie, particles with an aerodynamic diameter 2.5 μm [PM 2.5 ]) to be the fifth ranking worldwide mortality risk factor, with an attributed 4.2 million premature deaths. 1 Yet these impacts are not equally distributed. Worsening air quality, in conjunction with population growth, has driven absolute increases in air pollution-associated illness in low-and middle-income nations. Furthermore, while air quality has improved in high-income nations, geographic disparities persist among economically and racially disparate communities where air pollution remains stubbornly elevated. 2 Prioritizing air quality improvements in the most affected areas will yield the greatest public health benefits, but quantifying the level of improvement needed is an evolving question. Improvement in air quality can be attributed to policies that set regulatory air pollution standards or guidelines protective of human health. Epidemiological data and evidence are used by environmental agencies, such as the World Health Organization, the US Environmental Protection Agency, and the European Union, to determine appropriate regulatory targets for criteria air pollutants, including PM 2.5 , ozone, and nitrogen dioxide (NO 2). However, the decision-making behind regulatory standards relies on up-to-date exposure and health information derived using appropriate methods. In the US, the Clean Air Act requires an independent review of the most relevant air pollution and health literature assessed through a weight-of-evidence approach. Weight-of-evidence relies on the examination of multiple evidentiary lines crossing different scientific disciplines, including epidemiological cohorts, animal-based toxicologic studies, and controlled human exposures or clinical findings, to determine causality. 3 The strength of this approach is to ensure that identified air pollution and health effects are not restricted to a single line of study and consider the full body of scientific inquiry. So, why should we pursue studies of air pollution and health when the existing literature is so robust? The identification of appropriate regulatory thresholds depends on up-to-date investigations that support, dispute, or identify new air pollution and health associations. This observational study by Ma and colleagues 4 evaluated the association between acute PM 2.5 and NO 2 air pollution exposure with 8.96 million mortality events in 4 separate global regions: Jiangsu, China; California, US; south-central Italy; and Germany. The findings in the study by Ma et al 4 confirm previously identified associations of increased mortality with greater PM 2.5 and NO 2 exposure. 5 Ma et al 4 also observed heterogeneity in the strength of associations of mortality with the highest air pollution risks identified in south-central Italy for PM 2.5 and Germany for NO 2. However, the novel aspect of their work was the methodological application of a 2-way interactive fixed-effect model used to infer the air pollution and mortality association. Ma et al 4 argued that this econometric-derived approach has advantages over more traditional time-series modeling by controlling for both measured and unmeasured time-varying spatial unit-specific confounders. Ma and colleagues 4 further compared their findings with a more familiar time-series model and demonstrated robustness in the air pollution and mortality association using both approaches. This methodological comparison not only validates prior air pollution and health studies that use time-series methods 6 but provides evidentiary rigor for the validity of both methods when reconsidering regulatory standards. While the study by Ma et al 4 presents an alternative statistical approach for estimating air pollution health effects, there are other noteworthy advances in the air pollution and health literature. First, there have been new developments in air pollution exposure modeling. Initial

Background: Despite similar incidence rates among Black and White women, breast cancer mortality rates are 40% higher among Black women. More than half

Lead poisoning remains a persistent health issue for both humans and wildlife, despite strides to reduce lead contamination in the environment. Using Geographic Information Systems (GIS), this study explores the associations between blood lead levels (BLLs) in wildlife sentinels and possible built environment lead exposure risk factors in the Minneapolis-Saint Paul, Minnesota urban area. Results show a high-level of heterogeneity in animal BLLs (n = 472) across our urban environment and suggest that each kilometer increase in road density is associated with a 17.07% (95% CI: 1.48%, 35.05%) increase in BLL in our study species of Virginia opossums and Eastern gray squirrels, and a 14.28% (95% CI: 1.16%, 29.09%) increase in BLL of rock pigeons. For squirrels and opossums, we see an additional 5.72% (95% CI: 0.59%, 10.85%) increased risk of BLL for every 1000 people per square-mile. The relationship between animal sentinels and environmental hazards can give us an insight into the potential lead exposure risks for humans. The use of wildlife sentinel data to explore environmental risk factors supports a One Health approach to better address public health questions and aid in wildlife rehabilitation related to residual lead poisoning from ambient environmental exposures.

<h2>Abstract</h2><h3>Background</h3><p>Air pollution contributes to premature mortality, but potential impacts differ in populations with existing disease, particularly for individuals with multiple risk factors. While chronic obstructive pulmonary disease (COPD) increases vulnerability to air pollution, individuals with COPD and other individual risk factors are at the intersection of multiple risks and may be especially susceptible to the effect of acute outdoor air pollution.</p><h3>Research Question</h3><p>What is the association between wintertime air pollution and mortality in patients with COPD and the modifying role of individual risk factors?</p><h3>Study Design and Methods</h3><p>We evaluated 19,243 deceased Veterans with prior COPD diagnosis residing in 25 U.S. metropolitan regions (2016-2019). Electronic health records include patient demographics, smoking status, and comorbidities, such as asthma, coronary artery disease (CAD), obesity, and diabetes. Using geocoded addresses, individuals were assigned wintertime fine particulate matter (PM_2.5) and NO₂ air pollution exposures. We estimated associations between acute air pollution and mortality using a time-stratified case-crossover design with a conditional logistic model and assessed individual risk differences by stratified analysis.</p><h3>Results</h3><p>We estimated a 1.05 (95% CI: 1.02-1.09) mortality risk for each 10 <i>μ</i>g/m³ increase in daily wintertime PM_2.5. Older patients and African Americans showed elevated risk. Obesity was a substantial air pollution-related mortality risk factor (OR: 1.11; 95% CI: 1.01-1.23) and the estimated risk for individuals with obesity plus CAD or obesity plus diabetes was 16% higher.</p><h3>Interpretation</h3><p>Wintertime PM_2.5 exposure was associated with elevated mortality risk in people with COPD, but individuals with multiple comorbidities, notably obesity, had high vulnerability. Our study suggests that obesity, CAD, and diabetes are understudied modifiers of air pollution-related risks for people with existing COPD.</p>

Background The short-term association between increasing temperatures and injury has been described in high-income countries, but less is known for low-income and-middle-income countries, including Vietnam. Methods We used emergency injury visits (EIV) data for 2017–2019 from 733 hospitals and clinics in Hanoi, Vietnam to examine the effects of daily temperature on EIV. Time-series analysis with quasi-Poisson models was used to estimate a linear relative risk increase (RRI) for overall populations and ones stratified by age and sex. Exposure–response curves estimated non-linear associations as an RR between daily temperature and injury. Models were adjusted for the day of week, holidays, daily relative humidity, daily particulate matter, and long-term and seasonal trends. Results and conclusions A total of 39 313 EIV were recorded averaging 36 injuries daily. Injuries more likely occurred in males and those aged 15–44, and aged 44–60. For linear effects, a 5°C increase in same day mean temperature was associated with an overall increased EIV (RRI 4.8; 95% CI 2.3 to 7.3) with males (RRI 5.9; 95% CI 3.0 to 8.9) experiencing a greater effect than females (RRI 3.0; 95% CI −0.5 to 6.5). Non-linear effects showed an increase in EIV at higher temperatures compared with the threshold temperature of 15°C, with the greatest effect at 33°C (RR 1.3; 95% CI 1.2 to 1.6). Further research to investigate temperature-injury among different populations and by the cause of injury is warranted. Data may be obtained from a third party and are not publicly available. Data were provided by Hanoi Social Security.

Research on the public health significance of Ixodes scapularis ticks in the Midwest seldom focuses on extreme weather conditions that can modulate their population dynamics and ability to transmit pathogenic organisms. In this study, we assessed whether the distributional abundance of I. scapularis immatures is associated with current and time-lagged climatic determinants either directly or indirectly. We analyzed a 20-year longitudinal small mammal live-trapping dataset within a seven-county metropolitan area in Minnesota (1998–2016) using yearly tick counts at each site to assess whether inter- and intra-annual variation in immature I. scapularis counts is associated with climate and land-use conditions. We found that (1) immature I. scapularis ticks infesting mammals expanded southwesterly over the study period, (2) eastern chipmunks, Tamias striatus, supplied a substantial proportion of nymphal blood meals, (3) a suite of climatological variables are demonstrably associated with I. scapularis presence, and abundance across sites, most notably summer vapor pressure deficit, and (4) immature I. scapularis display an affinity for deciduous forests in metro areas. Our results suggest that climatic and land-type conditions may impact host-seeking I. scapularis ticks through numerous mechanistic avenues. These findings extend our understanding of the abiotic factors supporting I. scapularis populations in metro areas of the upper Midwest with strong implications for discerning future tick-borne pathogen risk.

<p>Background: Triple negative breast cancer (TNBC) is an aggressive subtype of invasive breast cancer that disproportionately affects Black women and contributes to racial disparities in breast cancer mortality. Prior research has found evidence of a link between TNBC risk and neighborhood/area-level measures of disadvantage, including socioeconomic status and racial segregation. This study evaluated additional area-level exposures as potential mediators of the relationship between neighborhood disadvantage and TNBC risk in New Castle County, DE, a region with elevated rates of TNBC. Methods: The study population included 3,316 Black and White adult female residents of New Castle County who were diagnosed with invasive breast cancer at the Helen F. Graham Cancer Center &amp; Research Institute (HFGCCRI) in Newark, DE from 2012-2020. Patient addresses were geocoded, and demographic and clinical measures were abstracted from the HFGCCRI cancer registry. Neighborhood and environmental exposure measures were generated from electronic health records (EHR), the US Census Bureau American Community Survey, and Environmental Protection Agency (EPA) Risk-Screening Environmental Indicator (RSEI) data; these measures were aggregated to the census tract and linked to patient geocodes. Included neighborhood exposure measures were factors that may influence patient-level exposure to well-known breast cancer risk factors, including alcohol use disorder (AUD) and diabetes prevalence, breastfeeding (assessed with the proxy measure ‘% single female-headed households with children’), and toxic environmental indicators (e.g., toxic release inventory sites). The relationships between these exposures and the odds of TNBC (relative to other subtypes of invasive breast cancer) were first evaluated on a univariate basis. Next, to estimate the relationship between cumulative exposure and TNBC odds, census tract risk scores were calculated by dichotomizing each exposure into low- and high-risk categories and summing the total of high-risk exposures. A multilevel logistic regression model was used to test the association between this risk score and TNBC odds while adjusting for patient-level age and race.Results: TNBC cases accounted for 14% (n = 453) of invasive breast cancer cases. Significantly higher odds of TNBC were observed for patients who reside in census tracts characterized by higher rates of AUD, diabetes, % single female-headed households with children, and RSEI scores. In the multilevel logistic regression model that adjusted for patient demographics, the cumulative exposure risk score was significantly associated with greater odds of TNBC. Conclusion: Results provide preliminary support for a link between TNBC odds and cumulative, area-level exposure to disordered alcohol use, metabolic disorders, lower breastfeeding rates, and toxic environmental indicators. Additional research evaluating the cumulative exposure risk score as a potentially modifiable mediator of the relationship between neighborhood disadvantage and TNBC risk will be presented.</p>

Background: Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality worldwide. Identifying both individual and community risk factors associated with higher mortality is essential to improve outcomes. Few population-based studies of mortality in COPD include both individual characteristics and community risk factors. Objective: We used geocoded, patient-level data to describe the associations between individual demographics, neighborhood socioeconomic status, and all-cause mortality. Methods: We performed a nationally representative retrospective cohort analysis of all patients enrolled in the Veteran Health Administration with at least one ICD-9 or ICD-10 code for COPD in 2016-2019. We obtained demographic characteristics, comorbidities, and geocoded residential address. Area Deprivation Index and rurality were classified using individual geocoded residential addresses. We used logistic regression models to assess the association between these characteristics and age-adjusted all-cause mortality. Results: Of 1,106,163 COPD patients, 33.4% were deceased as of January 2021. In age-adjusted models, having more comorbidities, Black/African American race (OR 1.09 [95% CI: 1.08-1.11]), and higher neighborhood disadvantage (OR 1.30 [95% CI: 1.28-1.32]) were associated with all-cause mortality. Female sex (OR 0.67 [95% CI: 0.65-0.69]), Asian race (OR 0.64, [95% CI: 0.59-0.70]), and living in a more rural area were associated with lower odds of all-cause mortality. After adjusting for age, comorbidities, neighborhood socioeconomic status, and rurality, the association with Black/African American race reversed. Conclusion: All-cause mortality in COPD patients is disproportionately higher in patients living in poorer neighborhoods and urban areas, suggesting the impact of social determinants of health on COPD outcomes. Black race was associated with higher age-adjusted all-cause mortality, but this association was abrogated after adjusting for gender, socioeconomic status, comorbidities, and urbanicity. Future studies should focus on exploring mechanisms by which disparities arise and developing interventions to address these.

Even early in the COVID-19 pandemic, adherence to physical distancing measures was variable, exposing some communities to elevated risk. While cognitive factors from the Health Belief Model (HBM) and resilience correlate with compliance with physical distancing, external conditions may preclude full compliance with physical distancing guidelines. Our objective was to identify HBM and resilience constructs that could be used to improve adherence to physical distancing even when full compliance is not possible. We examined adherence as expressed through 7-day non-work, non-household contact rates in two cohorts: 1) adults in households with children from Minnesota and Iowa; and 2) adults ≥50 years-old from Minnesota, one-third of whom had Parkinson’s disease. We identified multiple cognitive factors associated with physical distancing adherence, specifically perceived severity, benefits, self-efficacy, and barriers. However, the magnitude, and occasionally the direction, of these associations was population-dependent. In Cohort 1, perceived self-efficacy for remaining 6-feet from others was associated with a 29% lower contact rate (RR 0.71; 95% CI 0.65, 0.77). This finding was consistent across all race/ethnicity and income groups we examined. The barriers to adherence of having a child in childcare and having financial concerns had the largest effects among individuals from marginalized racial and ethnic groups and high-income households. In Cohort 2, self-efficacy to quarantine/isolate was associated with a 23% decrease in contacts (RR 0.77; 95% CI 0.66, 0.89), but upon stratification by education level, the association was only present for those with at least a Bachelor’s degree. Education also modified the effect of the barrier to adherence leaving home for work, increasing contacts among those with a Bachelor’s degree and reducing contacts among those without. Our findings suggest that public health messaging tailored to the identified cognitive factors has the potential to improve physical distancing adherence, but population-specific needs must be considered to maximize effectiveness.