Examining Management and Employees' Perceptions of Occupational Heat Exposure and the Effectiveness of a Heat Stress Prevention Intervention on Safety and Well-Being among Natural Gas Construction Workers: A Qualitative Field-Based Study.

BACKGROUND: Numerous risk factors have been identified as significantly influencing outdoor workers' risk for heat stress and heat-related conditions, impacting their health, well-being, and productivity. However, the specific effects of these factors on construction workers' safety, health, and well-being remain under-researched. With climate change increasing temperatures, assessing heat stress among construction workers is imperative. OBJECTIVE: To identify the barriers and facilitators influencing the safety of natural gas construction workers and evaluate an implemented heat stress intervention. METHODS: In the summer of 2023, two semi-structured interviews and six focus groups were conducted with twenty-one stakeholders at a Texas natural gas construction site. RESULTS: Key facilitators include employee preparedness, use of employer-provided resources, hydration logs, and real-time communication tools. Contrarily, the barriers include daily work schedules, access to dehydrating beverages, and generational differences with the non-implementation of mandatory rest breaks. The heat stress program was perceived as effective, surpassing recommended guidelines. CONCLUSION: To advance construction workers' safety, health, and well-being, both employee involvement and employer management are needed, along with no-cost accessible resources. Additionally, implementing a required routine rest break and comprehensive heat stress education, particularly for older workers, will significantly promote safety and safe work practices in hot environments. Note: in this study, the terms 'worker' and 'employee' are used interchangeably.

Applications of Artificial Intelligence for Heat Stress Management in Ruminant Livestock.

Heat stress impacts ruminant livestock production on varied levels in this alarming climate breakdown scenario. The drastic effects of the global climate change-associated heat stress in ruminant livestock demands constructive evaluation of animal performance bordering on effective monitoring systems. In this climate-smart digital age, adoption of advanced and developing Artificial Intelligence (AI) technologies is gaining traction for efficient heat stress management. AI has widely penetrated the climate sensitive ruminant livestock sector due to its promising and plausible scope in assessing production risks and the climate resilience of ruminant livestock. Significant improvement has been achieved alongside the adoption of novel AI algorithms to evaluate the performance of ruminant livestock. These AI-powered tools have the robustness and competence to expand the evaluation of animal performance and help in minimising the production losses associated with heat stress in ruminant livestock. Advanced heat stress management through automated monitoring of heat stress in ruminant livestock based on behaviour, physiology and animal health responses have been widely accepted due to the evolution of technologies like machine learning (ML), neural networks and deep learning (DL). The AI-enabled tools involving automated data collection, pre-processing, data wrangling, development of appropriate algorithms, and deployment of models assist the livestock producers in decision-making based on real-time monitoring and act as early-stage warning systems to forecast disease dynamics based on prediction models. Due to the convincing performance, precision, and accuracy of AI models, the climate-smart livestock production imbibes AI technologies for scaled use in the successful reducing of heat stress in ruminant livestock, thereby ensuring sustainable livestock production and safeguarding the global economy.

Climate change's implications for practice: Pharmacologic considerations of heat-related illness.

ABSTRACT: Climate change is the greatest threat to global health. As climate change worsens, heat waves will be longer, more intense, and more frequent. Increased health risks from climate change and heat waves include heat-related illness (HRI). HRI increases ED visits, hospitalizations, and mortality. Healthcare providers should be aware of the impact of medications on risk for HRI. This article elucidates signs and symptoms, populations at risk, drugs and mechanisms that increase risk, and patient education to reduce risk.

As Extreme Heat Becomes More Common, the Unprecedented Pacific Northwest Heat Dome Offers Lessons.

This Medical News article is an interview with emergency management and medical experts from Oregon and Washington who experienced the record-breaking heat wave in June of 2021.

Influence of acute heat mitigation strategies on core temperature, heart rate and aerobic performance in females: A systematic literature review.

This review examined the effect of acute heat mitigation strategies on physiological strain and exercise performance in females exercising in the heat. Three databases were searched for original research with an acute heat mitigation (intervention) and control strategy in active females and reporting core temperature, heart rate and/or aerobic exercise performance/capacity with ≥ 24°C wet bulb globe temperature. Hedges' g effect sizes were calculated to evaluate outcomes. Thirteen studies (n = 118) were included. Most studies that applied an acute heat mitigation strategy to females did not reduce thermal (9/10) or cardiovascular (6/6) strain or improve exercise performance/capacity (8/10). The most effective strategies for attenuating thermal strain were pre-cooling with ice-slurry (effect size = -2.2 [95% CI, -3.2, -1.1]) and ice-vests (-1.9 [-2.7, -1.1]), and pre- and per-cooling with an ice-vest (-1.8 [-2.9, -0.7]). Only pre-cooling with an ice-vest improved running performance (-1.8 [-2.9, -0.7]; ~0.43 min) whilst sodium hyperhydration improved cycling capacity at 70% V O2peak (0.8 [0.0, 1.6]; ~20.1 min). There is currently limited research on acute heat mitigation strategies in females, so the evidence for the efficacy is scarce. Some studies show beneficial effects with ice-slurry, ice-vests and sodium hyperhydration, which can guide future research to support female exercise performance in the heat.

Strategies to combat heat stress in Isa Brown layer hens: Unveiling the roles of vitamin A, vitamin E, vitamin K, vitamin C, selenium, folic acid, and in combination.

Background: Due to their efficient insulation, lack of sweat glands, relatively quick metabolic rate, and heightened sensitivity to heat, the poultry industry faces a serious problem with heat stress. Combining vitamins has been demonstrated to be more effective than implementing a single vitamin in reducing the effects of heat stress. Aim: This study aimed to investigate the efficacy of the multivitamin combination in feed on the growth performance, egg quality, and antioxidant enzymes in laying hens exposed to heat stress. Methods: A total of 28 Isa Brown strains aged 18 weeks were randomly designated into seven groups with four replications, i.e., (C-) normal temperature group, (C+) heat stress group, and the others with the administration of vitamin A and E (AE), vitamin K and C (KC), vitamin C and E (CE), vitamin E and selenium (ESE), and vitamin C and folic acid (CAF). Feed intake, feed efficiency, eggshell thickness, shape index, haugh unit (HU), yolk, and albumen index were evaluated at 22, 23, 24, and 25 weeks. Meanwhile, antioxidant enzymes were quantified at 22 and 25 weeks. Results: As a result, feed intake was reported a significant improvement in the AE and CE groups compared to the C+ group. Meanwhile, the feed efficiency was reported to be efficient in the CE and ESE groups. Based on egg quality evaluation, we reported significant shell thickness in the CE, ESE, and CAF groups compared to the C+; yolk index was reported slightly significant results in the AE and CAF groups; albumen index and HU were reported to increase significantly in the CAF group. Meanwhile, superoxide dismutase (SOD), malondialdehyde (MDA), and GPx activity were ameliorated significantly in the ESE and CAF groups. Conclusion: Combinations of multivitamins can thereby enhance feed intake, feed efficiency, egg quality, and antioxidant activity. The CE, ESE, and CAF groups were found to have made equivalent improvements in the eggshell thickness, shape index, HU, yolk, and albumen index.

Approach to heat-related illness.

OBJECTIVE: To describe heat-related illness and provide approaches for treatment in family practice. SOURCES OF INFORMATION: The MeSH terms heat-related illness and primary care were searched in PubMed. Clinical trials, practice reviews, and systematic reviews were included in this review. Reference lists were reviewed for additional articles. MAIN MESSAGE: Extreme heat events are increasing in frequency due to climate change and can directly result in heat exhaustion, heat stroke, or death. Exposure to extreme heat also exacerbates underlying health conditions. Patients may be at increased risk of heat-related illness because of underlying sensitivity to heat, increased exposure to heat, or barriers to resources. CONCLUSION: Family physicians can help prevent heat-related illness by identifying and counselling patients who are at increased risk and by advocating for interventions that reduce the chance of heat-related illness.

Aborder les troubles liés à la chaleur.

OBJECTIF: Décrire les troubles liés à la chaleur et présenter des stratégies de traitement en pratique familiale. SOURCES DE L'INFORMATION: Une recension à l'aide des expressions MeSH en anglais heat-related illness et primary care a été effectuée dans PubMed. Les essais cliniques, les évaluations de la pratique et les revues systématiques ont été inclus dans la présente révision. Les listes de références ont été examinées pour trouver des articles additionnels. MESSAGE PRINCIPAL: Les épisodes de canicule augmentent en fréquence en raison du changement climatique et peuvent directement causer un épuisement dû à la chaleur, un coup de chaleur ou la mort. L'exposition à la chaleur extrême peut aussi exacerber les problèmes de santé sous-jacents. Les patients peuvent être à risque accru d'un trouble lié à la chaleur à cause d'une sensibilité sous-jacente ou d'une plus grande exposition à la chaleur, ou encore en raison d'obstacles pour accéder aux ressources. CONCLUSION: Les médecins de famille peuvent aider à prévenir les troubles liés à la chaleur en identifiant les patients qui sont à risque plus élevé et en plaidant en faveur d'interventions qui réduisent le risque de tels troubles.

Turmeric essential oil improves intestinal integrity, immunological parameters, and performance of broiler chickens under cyclic heat stress.

This study aimed to examine whether dietary supplementation of broiler chickens with turmeric essential could mitigate the effects of cyclic heat stress conditions. Intestinal and immunological parameters and gene expression were evaluated during the grower phase. A total of 320 21-day-old male Cobb 500 broilers were distributed according to a completely randomized design with a 4 (diet) × 2 (environment) factorial arrangement and eight replications of five birds each. Dietary treatments consisted of a basal diet without essential oil (EO, negative control) and three diets containing low (100 mg kg-1), intermediate (200 mg kg-1), or high (300 mg kg-1) levels of turmeric EO. In the heat stress group, dietary supplementation with turmeric EO at 100 and 200 mg kg-1 improved body weight, feed conversion, breast yield, and relative liver weight. These supplementation levels reduced villus width, increased villus/crypt ratio, reduced the H/L ratio, and improved hepatic (HSP70 and SREBP1) and intestinal (OCLN) gene expression in birds under heat stress. These findings support the hypothesis that turmeric EO can be used to improve or restore intestinal integrity, modulate inflammation parameters, and, consequently, enhance the performance of broilers challenged by cyclic heat stress.

The Effect of Water Dousing on Heat Strain and Performance During Endurance Running in the Heat.

OBJECTIVES: Assess the effect of water dousing on heat strain and performance during self- and fixed-paced exercise in the heat. DESIGN: Crossover, block-randomized controlled trial. METHODS: Thirteen trained runners completed a 10-km time trial (TT) and 60-minute fixed-pace run (60% velocity of V˙O2max) in a 30.4 °C, 47.4% relative humidity environment using either water dousing (DOUSE) or no dousing (CON). RESULTS: Ten-kilometer TT performance was faster in DOUSE compared to CON (44:11 [40:48, 47:34] vs 44:38 [41:21, 47:56] min:s; P = .033). Change in core temperature (Tc) was not different between groups during the TT (+0.02 [-0.04, 0.07] °C in DOUSE; P = .853) or fixed-pace run (+0.02 [-0.15, 0.18] °C; P = .848). Change in mean skin temperature was lower in DOUSE during the TT (-1.80 [-2.15, -1.46] °C; P < .001) and fixed-pace run (-1.38 [-1.81, -0.96] °C; P < .001). Heart rate was lower for DOUSE during the fixed-pace run (-3.5 [-6.8, -0.2] beats/min; P = .041) but not during the TT (-0.2 [-2.5, 2.1] beats/min; P = .853). Thermal sensation was lower for DOUSE during the TT (-49.3 [-72.1, -26.1] mm; P < .001) and fixed-pace run (-44.7 [-59.7, -29.6] mm; P < .001). Rating of perceived exertion was not different between groups for the TT (-0.2 [-0.7, 0.3]; P = .390) or fixed-pace run (-0.2 [-0.8, 0.4]; P = .480). Sweat rate was lower for DOUSE for the TT (-0.37 [-0.53, -0.22] L/h; P < .001) and fixed-pace run (-0.37 [-0.48, -0.26] L/h; P < .001). CONCLUSION: Water dousing improves 10-km TT performance in the heat but does not affect Tc. The positive change in thermal perception (via lower skin temperature) during the TT likely drives this benefit.

Betaine and feed restriction as potential mitigation strategies against heat stress in two strains of laying hens.

Climate change is increasingly manifesting in temperate regions. Laying hens are highly sensitive to heat stress and mitigation strategies should be implemented to reduce the negative effects. The goal of this experiment was to evaluate the effects of betaine in drinking water (0.55 g/L) and 4 h feed restriction during peak heat stress on laying performance, egg quality, blood gas parameters, body temperature (Tb), and oxidative stress in 2 different breeds of laying hens. Therefore, 448 ISA Brown hens (25 wk) and 448 Lohmann LSL classic laying hens (26 wk) were housed in 128 cages (7 hens/cage). Thermoneutral (TN) data was collected for 21 d before cyclic heat stress (HS) (21d; 32 ± 2°C; 6 h daily). During HS, hens were divided into 4 treatments: 1) feed restriction (FR), 2) betaine supplementation in drinking water (BET), 3) feed restriction and betaine supplementation in drinking water (FR-BET), or 4) control (CON). The effects were evaluated after 1 wk of HS (acute heat stress; AHS) and 3 wk of HS (chronic heat stress; CHS). Laying rate and egg mass (EM) diminished during CHS but decreased more in white than brown hens (2.78% and 1.94%; -1.57% and -0.81%, respectively; P = 0.004) and remained unaltered by BET or FR. During AHS, average daily feed intake (ADFI) increased compared to TN, but the increase was higher in white than brown hens (6.36% and 2.62%, respectively; P = 0.001). Egg shell quality deteriorated during AHS and CHS, but was most affected in white hens, FR or BET did not impact this. Blood pCO2, HCO3- and base excess significantly decreased during AHS and CHS, but pH and iCa were unaltered. Blood glucose increased in white hens during AHS compared to TN (P < 0.001), while plasma malondialdehyde increased in brown hens (P < 0.001). Results indicated that laying hens experienced HS, but breed differences were observed and white hens were generally most affected. FR affected feed conversion ratio negatively during CHS. However, FR and BET could not improve laying performance, egg quality, Tb, or blood parameters during HS.

Performance Under Fire: Older Adult Cognitive Risks and Protections Under Heat Strain.

BACKGROUND AND OBJECTIVES: Although extreme heat events disproportionately affect older adults and the importance of cognition is known, research examining older adult cognition under heat stress is limited. This study examines the relationship between risk/protective factors and heat strain on older adult cognition, employing a social-ecological model. RESEARCH DESIGN AND METHODS: Retrieved from the 1996-2016 waves of the Health and Retirement Study, our study used older adults aged 50 and older and their spouses residing in the United States. Individual-fixed effects models estimated changes in cognition as measured by fluid and crystallized intelligence scores in response to extreme heat days. This study further estimated interactions of extreme heat with protective/risk factors for cognition (i.e., education, physical activity, social engagement, and genetic risk for Alzheimer's disease). RESULTS: Our results demonstrated that extreme heat days were associated with fluid but not crystallized intelligence scores. Educational attainment, mild physical activity, and social contacts with children moderated this relationship. Furthermore, Alzheimer's disease polygenic scores moderated the correlation between extreme heat days and crystallized intelligence scores. DISCUSSION AND IMPLICATIONS: An increasing frequency of extreme heat events and an aging population globally highlight the need for policies and interventions building resiliency in older adults. Actions promoting the protective modifiable behaviors to older adult cognition identified by our study can lead to healthier individuals and communities.

The health benefits of reducing micro-heat islands: A 22-year analysis of the impact of urban temperature reduction on heat-related illnesses in California's major cities.

This study investigates the relationship between temporal changes in temperatures characterizing local urban heat islands (UHIs) and heat-related illnesses (HRIs) in seven major cities of California. UHIs, which are a phenomenon that arises in the presence of impervious surfaces or the lack of green spaces exacerbate the effects of extreme heat events, can be measured longitudinally using satellite products. The two objectives of this study were: (1) to identify temperature trends in local temperatures to characterize UHIs across zip code tabulation areas (ZCTAs) in the seven observed cities over a 22-year period and (2) to use propensity score and inverse probability weighting to achieve exchangeability between different types of ZCTAs and assess the difference in hospital admissions recorded as HRIs attributable to temporal changes in UHIs. We use monthly land surface temperature data derived from MODIS Terra imagery from the summer months (June-September) from 2000 to 2022. We categorized ZCTAs (into three groups) based on their monthly land surface temperature trends. Of the 216 ZCTAs included in this study, the summertime land surface temperature trends of 43 decreased, while 161 remained unchanged, and 12 increased. Los Angeles had the greatest number of decreased ZCTAs, San Diego and San Jose had the highest number of increased ZCTAs. To analyze the number of monthly HRI attributable to changes in UHI, we used inverse probability of treatment weighting to analyze the difference in HRI between the years of 2006 and 2017 which were two major extreme heat events over the entire State. We observed an average reduction of 3.2 (95 % CI: 0.5; 5.9) HRIs per month and per ZCTAs in decreased neighborhoods as compared to unchanged. This study emphasizes the importance of urban climate adaptation strategies to mitigate the intensity and prevalence of UHIs to reduce health risks related to heat.

Efficacy of the FIFA cooling break heat policy during an intermittent treadmill football simulation in hot conditions in trained males.

OBJECTIVE: To evaluate the efficacy of the Fédération Internationale de Football Association (FIFA) cooling break policy against alternative cooling configurations in attenuating thermal strain during simulated football in the heat. METHODS: 12 males (age: 27±6 years, V̇O2peak: 61±7 mL/kg/min) completed five 90 min intermittent treadmill football match simulations in 40°C and 41% relative humidity (32°C wet-bulb globe temperature) with different cooling configurations: regular match without cooling breaks (REG), 3 min breaks without cooling (BRKno-cool), 3 min breaks with cooling (BRKcool: current FIFA policy; chilled fluid ingestion and ice towel across neck and shoulders), 5 min extended half-time without cooling breaks (ExtHTonly) and 3 min cooling breaks with 5 min ExtHT (ExtHTcool). Rectal temperature (Tre), heart rate, whole-body sweat rate (WBSR) and rating of perceived exertion (RPE) were recorded. Data are presented as mean (95% CIs). RESULTS: Final Tre was lower in BRKno-cool (0.20°C (0.01, 0.39), p=0.038), BRKcool (0.39°C (0.21, 0.57), p<0.001) and ExtHTcool (0.40°C (0.22, 0.58), p<0.001) than REG (39.1°C (38.8, 39.3)). Mean Tre was lower in ExtHTcool (38.2°C (38.0, 38.4)) than BRKcool (38.3°C (38.1, 38.5), p=0.018), BRKno-cool and ExtHTonly (38.4°C (38.2, 38.6), p<0.001) and REG (38.5°C (38.3, 38.7), p<0.001). Mean heart rate was lower during BRKcool (6 beats/min (4, 7), p<0.001) and ExtHTcool (7 beats/min (6, 8), p<0.001) compared with REG. WBSR was comparable across trials (p≥0.07) and RPE was attenuated during BRKcool (0.4 (0.1, 0.7), p=0.004) and ExtHTcool (0.5 (0.2, 0.7), p=0.002), compared with REG. CONCLUSION: BRKcool and ExtHTcool attenuated thermal, cardiovascular and perceptual strain during a simulated football match in the heat. Additional strategies may be required in field settings or under harsher conditions.

Rumen-protected methionine modulates body temperature and reduces the incidence of heat stress temperatures during the hottest hours of the day of grazing heat-stressed Bos indicus beef cows.

This study evaluated the effects of supplementation of rumen-protected methionine (RPM) on body thermoregulation and conception rate of Nelore cows exposed to high temperature-humidity index (THI). On -31 days before the artificial insemination protocol, 562 lactating, multiparous cows were assigned to receive (MG) or not (CG) RPM supplementation (3 g/cow mixed into 100 g of mineral supplement). Both groups remained in tropical pastures and received supplementation for 77 days. A subset of cows (n = 142) remained with an intravaginal thermometer collecting intravaginal temperature (IT). The respective minimum, average, and maximum environmental THI were 72.8, 78.0, and 83.3. Effects of treatment × hour of the day were detected (P < 0.0001) for IT. From 1330 to 1730 h and 1830 to 1900 h, IT was higher (P < 0.05) for CG versus MG cows when exposed to moderate and high THI. The supplementation with RPM did not affect conception rate (CG = 64.4% vs. MG = 58.2%; P > 0.05). In conclusion, 3 g of RPM supplementation lowered internal body temperature and possibly altered critical THI threshold in Nelore cows with no impact on reproduction.

Heat-related risk at Paris 2024: a proposal for classification and review of International Federations policies.

Several International Federations (IFs) employ specific policies to protect athletes' health from the danger of heat. Most policies rely on the measurement of thermal indices such as the Wet Bulb Globe Temperature (WBGT) to estimate the risk of heat-related illness. This review summarises the policies implemented by the 32 IFs of the 45 sports included in the Paris 2024 Olympic Games. It provides details into the venue type, measured parameters, used thermal indices, measurement procedures, mitigation strategies and specifies whether the policy is a recommendation or a requirement. Additionally, a categorisation of sports' heat stress risk is proposed. Among the 15 sports identified as high, very high or extreme risk, one did not have a heat policy, three did not specify any parameter measurement, one relied on water temperature, two on air temperature and relative humidity, seven on WBGT (six measured on-site and one estimated) and one on the Heat Stress Index. However, indices currently used in sports have been developed for soldiers or workers and may not adequately reflect the thermal strain endured by athletes. Notably, they do not account for the athletes' high metabolic heat production and their level of acclimation. It is, therefore, worthwhile listing the relevance of the thermal indices used by IFs to quantify the risk of heat stress, and in the near future, develop an index adapted to the specific needs of athletes.

Firefighter uncompensable heat stress results in excessive upper body temperatures measured by infrared thermography: Implications for cooling strategies.

This research sought to evaluate the thermal zones of the upper body and firefighter personal protective equipment (PPE) immediately following uncompensable heat stress (0.03 °C increase/min). We hypothesized that the frontal portion of the head and the inside of the firefighter helmet would be the hottest as measured by infrared thermography. This hypothesis was due to previous research demonstrating that the head accounts for ∼8-10% of the body surface area, but it accounts for ∼20% of the overall body heat dissipation during moderate exercise. Twenty participants performed a 21-min graded treadmill exercise protocol (Altered Modified Naughton) in an environmental chamber (35 °C, 50 % humidity) in firefighter PPE. The body areas analyzed were the frontal area of the head, chest, abdomen, arm, neck, upper back, and lower back. The areas of the PPE that were analyzed were the inside of the helmet and the jacket. The hottest areas of the body post-exercise were the frontal area of the head (mean: 37.3 ± 0.4 °C), chest (mean: 37.5 ± 0.3 °C), and upper back (mean: 37.3 ± 0.4 °C). The coldest area of the upper body was the abdomen (mean: 36.1 ± 0.4 °C). The peak temperature of the inside of the helmet increased (p < 0.001) by 9.8 °C from 27.7 ± 1.6 °C to 37.4 ± 0.7 °C, and the inside of the jacket increased (p < 0.001) by 7.3 °C from 29.2 ± 1.7 °C to 36.5 ± 0.4 °C. The results of this study are relevant for cooling strategies for firefighters.