Heat Health Risk Research Articles

Extreme Heat and Occupational Health Risks.

Climate change poses a significant occupational health hazard. Rising temperatures and more frequent heat waves are expected to cause increasing heat-related morbidity and mortality for workers across the globe. Agricultural, construction, military, firefighting, mining, and manufacturing workers are at particularly high risk for heat-related illness (HRI). Various factors, including ambient temperatures, personal protective equipment, work arrangements, physical exertion, and work with heavy equipment may put workers at higher risk for HRI. While extreme heat will impact workers across the world, workers in low- and middle-income countries will be disproportionately affected. Tracking occupational HRI will be critical to informing prevention and mitigation strategies. Renewed investment in these strategies, including workplace heat prevention programs and regulatory standards for indoor and outdoor workers, will be needed. Additional research is needed to evaluate the effectiveness of interventions in order to successfully reduce the risk of HRI in the workplace.

Extreme Heat and Pregnancy: A Content Analysis of Heat Health Risk Communication by US Public Health Agencies.

Exposure to extreme heat events increases the risk for negative birth outcomes, including preterm birth. This study sought to determine the presence and content of web-based heat health information for pregnant people provided by federal, state, and local government public health websites. This website content analysis consisted of 17 federal, 50 state, and 21 city websites, and noted which of 25 recognized pregnancy heat health data elements were included. Data for the analysis were collected from March 12, 2022, through March 16, 2022. The search identified 17 federal websites, 38 state websites, and 19 city websites with heat health information. Within these, only seven websites listed pregnant people as a vulnerable or at-risk population, and only six websites provided information related to heat health specifically for pregnancy. Of the 25 themes recognized as important for pregnancy risk during extreme heat exposure, only 11 were represented within these 6 websites. The presence of web-based pregnancy heat health information is infrequent and limited in content. Boosting web-based publication of extreme heat and pregnancy risks could mitigate negative maternal and child health outcomes.

Urban design and planning for extreme heat: an empirical study of built environment professionals’ perceptions in South East Queensland, Australia

ABSTRACT Extreme heat is currently Australia’s deadliest natural hazard. The intensity of heat events is increasing due to climate change, and further exacerbated by urban heat islands. Urban design and planning solutions can assist in reducing heat-health risks, but they are rarely implemented. Through semi-structured interviews and an online survey, we investigated the role of such solutions in planning and urban design practice in South-East Queensland, Australia. The results showed planning professionals had lower awareness of the role urban design and planning played in heat mitigation and adaptation strategies compared to urban designers and architects. Continued professional development and a greater inclusion of heat mitigation design provisions in Queensland’s planning system and Australian planning education are outlined as future requirements.

Increased temperatures and child health outcomes: a systematic review

Abstract Background Increased ambient temperatures and extreme heat events are well-established risk factors for increased mortality and morbidity. Most studies to-date have focused on the effect of high temperature on adult populations. However, the paediatric population is vulnerable to increased temperatures, due to a combination of physiological and social vulnerabilities characteristic of children. This presentation will present the findings of a systematic review and meta-analysis on increased heat and childhood health risks. Methods A literature search was carried out of three scientific databases: Pubmed, Embase, and SCOPUS. The data was pooled and summarised in statistical meta-analysis, and presented as relative risk (RR) scores. Subgroup analyses by disease category, gender, and climate group were carried out. Studies not meeting criteria for statistical meta-analysis were summarised in narrative review. Results There is evidence that increased heat increases all-cause mortality in the paediatric population. Increased heat is a risk factor for morbidity throughout the childhood years, from increased rates of preterm birth, to increased adolescent mental health presentations. There is evidence that heat increases the risk of SIDS, respiratory, heat illness, renal disease, mental health, and infectious diseases in children. The majority of studies which quantified the relationship between increased heat and illness do not separate children from adults in statistical analyses. Conclusions There is a substantial body of evidence demonstrating that children have higher rates of morbidity and mortality as a result of higher than usual temperatures. Further research is required into the effects of global warming on child health, and more research is needed to establish protective factors. Researchers in environmental health should consider sub-group analyses on children to identify risks particular to this vulnerable population Key messages • Children are at increased risks of multiple diseases in hot temperatures or heatwaves. • More research is needed into the unique impact of climate change on children.

Container buildings used for residential and business purposes in Johannesburg, South Africa and potential heat-related health risks.

Outdoor and indoor air temperature affects human health and wellbeing. Climate change projections suggest that global temperatures will continue to increase, and this poses a threat to health. Buildings (for housing and business purposes) that can protect humans from the adverse effects of temperature are essential, especially in the context of climate change. In this cross-sectional study, we measured the indoor temperature inside shipping containers comprising a seven-storey block of apartments and businesses in Johannesburg, South Africa for 14 days. We assessed indoor temperature and relative humidity; evaluated measured temperatures in relation to thresholds known to be associated with adverse health risks; and sought to understand heat-health perceptions and symptoms of people living and working in shipping container units. Median indoor apparent temperature (AT) (a combination of temperature and relative humidity) was 16°C with values ranging from 6°C (observed at 8:00) to 42°C (observed at 17:00). Insulated units had temperatures between 2°C and 9°C cooler than the uninsulated unit. Heat-health risks from AT exposure were likely in all units, although there was variation in the number of occurrences that AT measurements exceeded the four symptom bands of caution, extreme caution, danger and extreme danger. Indoor AT was found to be 7°C higher on average when compared to outdoor AT. Some participants believed that their units were hot during hot weather and most people opened windows or did nothing during hot weather. Few participants reported experiencing adverse heat-health impacts, except for experiencing headaches (58%) and feeling tired or weak (40%). Residents, tenants, or business owners using shipping containers should consider insulation installation and adequate windows/air conditioning for ventilation, especially in hot climates. Further research and awareness regarding heat-health risks of living or working in these spaces is needed.

Reducing heat risk for people experiencing unsheltered homelessness

Planners and policymakers are increasingly interested in heat resilience, but there is little evidence about heat exposure, health risks, and adaptive strategies among people experiencing homelessness. We took a nested, mixed-methods approach. First we identified where unhoused residents in Santa Clara County were disproportionately exposed to heat, and then examined how unhoused residents in these areas coped with heat and avoided heat-related illness. In the first stage, we used descriptive and spatial analyses to identify associations between unhoused residents, tree canopy, temperature, and other neighborhood characteristics. The neighborhoods in the top quartile of unhoused residents were two percent hotter than other neighborhoods demonstrating a dimension of urban thermal inequity. In the second stage, we conducted in-depth (n = 10) and encampment-based (n = 72) interviews with unhoused people to better understand their heat-related experiences and needs. We found that unhoused participants were exposed to extreme heat, which resulted in negative health consequences. Unhoused residents favored staying in places where they had more stability and were less likely to be “swept” (relocated). But, the more stable locations tended to have less access to shade and water, thus they faced difficult trade-offs. Additionally, many unhoused participants experienced challenges accessing air-conditioned spaces, including cooling centers, due to lack of information, transportation issues, and restrictive policies. The most important strategy for reducing the unhoused population's heat risk is housing provision, and interim approaches include outdoor spaces for unhoused people designed with heat considerations in mind, and inclusive air-conditioned indoor spaces.

A novel climate and health decision support platform: Approach, outputs, and policy considerations

BackgroundThe adverse health impacts of climate change are increasingly apparent and the need for adaptation activities is pressing. Risks, drivers, and decision contexts vary significantly by location, and high-resolution, place-based information is needed to support decision analysis and risk reduction efforts at scale. MethodsUsing the Intergovernmental Panel on Climate Change (IPCC) risk framework, we developed a causal pathway linking heat with a composite outcome of heat-related morbidity and mortality. We used an existing systematic literature review to identify variables for inclusion and the authors’ expert judgment to determine variable combinations in a hierarchical model. We parameterized the model for Washington state using observational (1991–2020 and June 2021 extreme heat event) and scenario-driven temperature projections (2036–2065), compared outputs against relevant existing indices, and analyzed sensitivity to model structure and variable parameterization. We used descriptive statistics, maps, visualizations and correlation analyses to present results. ResultsThe Climate and Health Risk Tool (CHaRT) heat risk model contains 25 primary hazard, exposure, and vulnerability variables and multiple levels of variable combinations. The model estimates population-weighted and unweighted heat health risk for selected periods and displays estimates on an online visualization platform. Population-weighted risk is historically moderate and primarily limited by hazard, increasing significantly during extreme heat events. Unweighted risk is helpful in identifying lower population areas that have high vulnerability and hazard. Model vulnerability correlate well with existing vulnerability and environmental justice indices. DiscussionThe tool provides location-specific insights into risk drivers and prioritization of risk reduction interventions including population-specific behavioral interventions and built environment modifications. Insights from causal pathways linking climate-sensitive hazards and adverse health impacts can be used to generate hazard-specific models to support adaptation planning.

Health-integrated heat risk assessment in Australian cities

Extreme heat, also known as the silent killer that conceal its lethal effect behind heat-related deaths, has become one of the deadliest natural hazards globally. However, the evaluation of heat risks in many countries remains incomplete, overlooking an important component on population health conditions in the evaluation framework. Drawing on the IPCC's risk assessment framework, this study presents, for the first time, a comprehensive heat health risk assessment in Australian capital cities, consisting of three individual indexes—the heat exposure index, heat hazard index and heat vulnerability index—at the finest census unit, and an overall heat health risk index (HHRI). By involving health-related indicators in heat risk assessment, our evaluation takes into account people's sensitivity to heat in developing the heat health risk indexes. Using the HHRI, we identify high heat risk areas appearing primarily in higher density residential areas with some distances away from the inner cities. We also find that the inequity of demographic and socioeconomic characteristics, housing features, and built environment features exists in areas with different levels of heat risks. Our findings contribute not only to profiling heat risks in Australian cities, but also empirically advance our understanding of place-based risk reduction in the Southern Hemisphere by linking climate science with health and spatial science research.

Spatial heterogeneity of driving factors for urban heat health risk in Chongqing, China: A new identification method and proposal of planning response framework

With urban heat challenges increasingly severe, assessing heat health risk has become crucial for human settlements. Unfortunately, previous studies have not accurately identified the driving factors, posing a significant obstacle to translating assessment results into policymaking. Particularly, potential spatial heterogeneity of driving factors at the indicator-level may exist. Therefore, this study developed a systematic method to examine the spatial heterogeneity of driving factors for heat health risk in Chongqing. Based on this heterogeneity, an integrated framework linking heat health risk, driving factors, and response strategies was proposed, supporting specific solutions for different cities. The results indicate that driving factors exhibit strong heterogeneity at the indicator-level. Even within the same prevention zone and urban functional areas, the maximum differences in the number of driving factors and combination categories can reach four and five, respectively. Moreover, relying solely on the driving factors obtained through traditional methods to develop cooling measures is unreasonable. When these driving factors are consistent, there are still, on average, six combinations of driving factors at the indicator-level, and each combination includes an average of 2.9 indicators. The higher the level of the risk prevention zone, the more driving factors it contains. The average number of driving factors above the moderate risk level is 3.9, higher than the 1.1 and 2 found in moderate and below moderate risk levels. Overall, this study provides a reference for understanding spatial heterogeneity of driving factors for heat health risk and offers an approach to assist policymakers in formulating guided cooling strategies.

Heat-health governance in a cool nation: A case study of Scotland

Under climate change, many parts of the world are warming with increasing frequencies and intensities of heatwaves, bringing heat-health risks to places including those that have a historically temperate or cool climate. These places may have extensive experience in managing cold-health risks, while experience is lacking in dealing with heat-health risks due to their lack of historical exposure to high temperatures. This paper explores this overlooked area of the challenges and opportunities of heat-health governance in cool places using Scotland as a case study. Various important themes of heat-health governance in cool places were identified by the study, including socio-cultural barriers to intervention, vulnerable population overlaps, temporal and geographical scales, and governance arrangements. The study found challenges in managing heat-health risks including a perceived lack of heat-health risks and policy priority as well as unsuitable building stock. Meanwhile, it also identified opportunities for governing cold and heat risks holistically within existing institutional systems and creating co-benefits of improving communication and information dissemination, reducing inequality and improving indoor thermal comfort of both cold and heat as well as providing good quality greenspace. Our findings contribute to the development or improvement of national/regional strategies to manage heat-health risks not only in Scotland but also in other places with a historically cool or temperate climate.

Migrants from Low-Income Countries have Higher Heat-Health Risk Profiles Compared to Native Workers in Agriculture

The present observational study was conducted to uncover potential differences in the risk of experiencing high occupational heat strain during agriculture work between migrants and their native coworkers, as well as to elucidate the factors that may contribute to such differences. The study took place over the period from 2016 through 2019 and involved monitoring 124 experienced and acclimatized individuals from high-income (HICs), upper-middle-income (UMICs), as well as lower-middle- and low-income (LMICs) countries. Baseline self-reported data for age, body stature, and body mass were collected at the start of the study. Second-by-second video recordings throughout the work shifts were captured using a video camera and were used to estimate workers’ clothing insulation, covered body surface area, and body posture, as well as to calculate their walking speed, the amount of time they spent on different activities (and their intensity) and unplanned breaks throughout their work shifts. All information derived from the video data was used to calculate the physiological heat strain experienced by the workers. The core temperature of migrant workers from LMICs (37.81 ± 0.38 °C) and UMICs (37.71 ± 0.35 °C) was estimated to be significantly higher compared to the core temperature of native workers from HICs (37.60 ± 0.29 °C) (p < 0.001). Moreover, migrant workers from LMICs faced a 52% and 80% higher risk for experiencing core body temperature above the safety threshold of 38 °C compared to migrant workers from UMICs and native workers from HICs, respectively. Our findings show that migrant workers originating from LMICs experience higher levels of occupational heat strain, as compared to migrant workers from UMICs and native workers from HICs, because they take fewer unplanned breaks during work, they work at a higher intensity, they wear more clothing, and they have a smaller body size.

Cooler and Healthier: Increasing Tree Stewardship and Reducing Heat-Health Risk Using Community-Based Urban Forestry

Heat exposure poses health risks that disproportionately burden disadvantaged communities. Trees protect against heat, but significant barriers exist to growing robust urban forests. In drier climates, complex logistics of watering during a multi-year establishment period pose a challenge because street trees are typically unirrigated and funding for maintenance is generally unavailable. This study tested the impacts of varying theory-guided community engagement approaches on beliefs, attitudes, knowledge, and behaviors related to foster street tree stewardship and individual-level heat mitigation actions in 116 households in Los Angeles County, USA. We tested a control intervention against experimental messaging focused on either public health or environmental health, and also segmented participants by the degree of prior household engagement with a local tree planting group. Outcomes measured were soil moisture, tree health, and survey responses indicating benefits and barriers related to tree stewardship. Results indicate that intervention messages had limited effect on these outcomes, and that level of engagement by the tree planting group was a stronger predictor of tree stewardship. We also found that tree stewardship correlated positively to heat protection measures, suggesting that environmental engagement may be an effective portal to reducing heat risk.

Planning to Reduce the Health Impacts of Extreme Heat: A Content Analysis of Heat Action Plans in Local United States Jurisdictions.

Objectives. To examine commonalities and gaps in the content of local US heat action plans (HAPs) designed to decrease the adverse health effects of extreme heat. Methods. We used content analysis to identify common strategies and gaps in extreme heat preparedness among written HAPs in the United States from jurisdictions that serve municipalities with more than 200 000 residents. We reviewed, coded, and analyzed plans to assess the prevalence of key components and strategies. Results. All 21 plans evaluated incorporated data on activation triggers, heat health messaging and risk communication, cooling centers, surveillance activities, and agency coordination, and 95% incorporated information on outreach to at-risk populations. Gaps existed in the specific applications of these broad strategies. Conclusions. Practice-based recommendations as well as future areas of research should focus on increasing targeted strategies for at-risk individuals and expanding the use of surveillance data outside of situational awareness. (Am J Public Health. 2023;113(5):559-567. https://doi.org/10.2105/AJPH.2022.307217).

High-resolution thermal exposure and shade maps for cool corridor planning

Shade is crucial for thermally comfortable cities that promote physical activity. City-wide shade and thermal exposure data are essential for managing heat health risks but are difficult to obtain at fine scales due to limited sensing and modeling capabilities. To address this gap and assist municipalities with "cool corridor" planning, we generated 1-m resolution shade and mean radiant temperature (TMRT) maps from LiDAR point clouds for the Phoenix-Tempe metropolitan area using the SOLWEIG model. TMRT estimates were validated using 763 observations with a mobile human-biometeorological 6-directional setup. SOLWEIG had an overall RMSE of 5.6°C with an error of 6.2°C at open sites, 5.4°C under trees, and 4.4°C in building canyons. Hourly TMRT and shade maps were generated from 7:00 h to 20:00 h for June 27, 2012, a typical clear, dry, calm summer day. We assessed sidewalk shade coverage based on the Maricopa Association of Government's Active Transportation Plan. Only 8% of all sidewalks met the recommended minimum of 20% shade coverage at all times. Less than 50% of all sidewalks met the goal for parts of the day, indicating that the urban area is not walkable during extreme heat. Results from this study will inform municipal cool corridor planning to optimize site selection for heat mitigation.

The Economic Value of Health Benefits Associated with Urban Park Investment.

The allocation of resources towards the development and enhancement of urban parks offers an effective strategy for promoting and improving the health and well-being of urban populations. Investments in urban parks can result in a multitude of health benefits. The increased usage of greenspace by park users has been linked to positive physical and mental health outcomes. Additionally, the expansion of greenspace in urban areas can mitigate harmful impacts from air pollutants, heat, noise, and climate-related health risks. While the health benefits attributed to urban parks and greenspaces are well documented, few studies have measured the economic value of these benefits. This study applied a novel ecohealth economic valuation framework to quantify and estimate the potential economic value of health benefits attributed to the development of a proposed park in the downtown core of Peterborough, Canada. The results indicated that development of the small urban park will result in annual benefits of CAD 133,000 per year, including CAD 109,877 in the avoided economic burden of physical inactivity, CAD 23,084 in health savings associated with improved mental health, and CAD 127 in health savings attributed to better air quality. When including the economic value of higher life satisfaction, the economic benefit is more than CAD 4 million per year. The study demonstrates the value of developing and enhancing urban parks as a strategy to improve population health and well-being, and as a means of cost savings to the medical system.

Heatwaves, hospitals and health system resilience in England: a qualitative assessment of frontline perspectives from the hot summer of 2019

ObjectiveTo critically assess the impacts of very hot weather on (i) frontline staff in hospitals in England and (ii) on healthcare delivery and patient safety.Study designA qualitative study design using...

SURFACE URBAN HEAT ISLANDS AND RELATED HEALTH RISK IN THE PHILIPPINES: A GEOSPATIAL ASSESSMENT USING MODIS DATA

Abstract. The study assessed the heat-health risk of the Philippines during 2020 using the MODIS derived Urban Heat Island (UHI) and gridded population data. The study found out that the urban areas experienced more intense heat than the rural areas. It also revealed that the UHI is more intense during March, April and Month or hot dry season. People living in Metro Manila are more exposed and vulnerable to the heat risk. Poverty is one reason that puts people exposed and vulnerable to the heat risk. The output of this study can aid decision-makers especially the urban planners.

Developing a Healthy Environment Assessment Tool (HEAT) to Address Heat-Health Vulnerability in South African Towns in a Warming World.

Prolonged exposure to high temperatures can cause heat-related illnesses and accelerate death, especially in the elderly. We developed a locally-appropriate Healthy Environment Assessment Tool, or 'HEAT' tool, to assess heat-health risks among communities. HEAT was co-developed with stakeholders and practitioners/professionals from the Rustenburg Local Municipality (RLM), a setting in which heat was identified as a risk in an earlier study. Feedback was used to identify vulnerable groups and settings in RLM, consider opportunities and barriers for interventions, and conceptualize a heat-health vulnerability assessment tool for a heat-resilient town. Using information provided by the RLM Integrated Development Plan, the HEAT tool was applied in the form of eight indicators relating to heat-health vulnerability and resilience and areas were evaluated at the ward level. Indicators included population, poverty, education, access to medical facilities, sanitation and basic services, public transport, recreation/community centres, and green spaces. Out of 45 wards situated in the municipality, three were identified as critical risk (red), twenty-eight as medium-high risk (yellow), and six as low risk (green) in relation to heat-health vulnerability. Short-term actions to improve heat health resilience in the community were proposed and partnerships between local government and the community to build heat health resilience were identified.

Urban heat health risk assessment in Singapore to support resilient urban design — By integrating urban heat and the distribution of the elderly population

Elderly people are more vulnerable than other age groups to the increasing urban heat risk caused by both climate change and urbanization. This study developed a systematic method to assess the urban heat health risk to the aging population in high-density tropical cities. Based on the assessment, the study identifies high heat health risk districts, diagnoses specific reasons in individual districts, and suggests specific solutions. First, we applied an existing GIS model to quantitatively evaluate urban heat island (UHI) intensity, which is influenced by both longwave radiation and anthropogenic heat. Second, the urban heat health risk to the elderly in individual districts was weighted by UHI intensity, density and proportion of the elderly population in different districts. The integrated mapping results showed that the old HDB neighborhoods in the Central Region are at the highest risk, with a higher UHI intensity, density and proportion of the elderly population than other districts. Based on the analysis, we suggest both UHI mitigation strategies, social support, and facilities for the elderly population at Singapore HDB neighborhoods. Research outputs allow different stakeholders to understand various issues of individual neighborhoods regarding the urban heat health risk to the elderly and to develop corresponding solutions. • A new method is developed to assess heat health risks on aging population, by heat, exposure, and vulnerability. • GIS overlapping map is used to identify specific heat health risk reasons at districts. • Nighttime air temperature is used to assess urban heat health issue, rather than land surface temperature. • Older neighborhoods in the Central Region of Singapore are at the highest risk. • Both adaptation and mitigation recommendations are provided to develop systematic and specific strategies.

Evaluating the Applicability and Health Benefits of the Graded Heat Health Risk Early Warning Model - Jinan City, Shandong Province, China, 2022.

The heat health early warning model serves as an effective strategy for reducing health risks related to heatwaves and improving population adaptability. Several high-income countries have taken the lead in conducting research and implementing measures aimed at safeguarding their populations. The graded heat health risk early warning model (GHREWM) in Jinan City has demonstrated efficacy in safeguarding males, females, individuals aged above 75 years, and those with cardiopulmonary diseases. During the summer of 2022, the warning stage of GHREWM contributed to the prevention of 10.9 deaths per million individuals, concurrently averting health-related economic losses estimated at approximately 227 million Chinese Yuan (CNY). The GHREWM has the potential to enhance cities' adaptability to climate change. It is crucial to incorporate additional adverse health endpoint data in the development of early warning models, as this will improve their applicability and protective efficacy.