Adverse Effects Of Heat Research Articles

345Occupational heat stress and economic burden: evidence to support development of workplace heat management policies

Abstract Background The adverse effects of heat on workers’ health and work productivity are well documented. However, the resultant economic consequences and productivity loss are less understood. This review aims to summarize the retrospective and potential future economic burden of workplace heat exposure in the context of climate change. Methods Literature was searched from database inception to October 2020 using Embase, PubMed, and Scopus. Articles were limited to original human studies investigating costs from occupational heat stress in English. Results Twenty studies met the criteria. Eighteen studies estimated costs from heat-induced labor productivity loss. Predicted global costs from lost worktime, in US$, were 280 billion in 1995, 311 billion in 2010 (≈0.5% of GDP), 2.5 trillion in 2030 (>1% of GDP) and up to 4.0% of GDP by 2100, with additional expenses after considering reduced work efficiency. Three studies estimated heat-related healthcare expenses from occupational injuries with averaged annual costs (US$) exceeding 1 million in Spain, 1 million in Guangzhou, China and 250,000 in Adelaide, Australia. Low- and middle-income countries and countries with warmer climates had greater losses as a proportion of GDP. Greater costs per worker were observed in outdoor industries, amongst males, and workers aged 25 to 44 years. Conclusions The estimated global economic burden of occupational heat stress is substantial. Climate change adaptation and mitigation strategies should be implemented to likely minimize future costs. Further research exploring the relationship between occupational heat stress and related expenses from lost productivity, decreased work efficiency and healthcare, and costs stratified by demographic factors, is warranted. Key messages The estimated retrospective and future economic burden from occupational heat stress is large. Responding to climate change is crucial to minimize this burden. Analyzing heat-attributable occupational costs may guide the development of workplace heat management policies and practices as part of global warming strategies.

Occupational heat stress and economic burden: A review of global evidence

BACKGROUND AND AIM: The adverse effects of heat on workers’ health and work productivity are well documented. However, the resultant economic consequences and productivity loss are less understood. This review aims to summarize the retrospective and potential future economic burden of workplace heat exposure in the context of climate change. METHODS: Literature was searched from database inception to October 2020 using Embase, PubMed, and Scopus. Articles were limited to original human studies investigating costs from occupational heat stress in English. RESULTS:Twenty studies met criteria for inclusion. Eighteen studies estimated costs secondary to heat-induced labor productivity loss. Predicted global costs from lost worktime, in US$, were 280 billion in 1995, 311 billion in 2010 (≈0.5% of GDP), 2.4–2.5 trillion in 2030 (1% of GDP) and up to 4.0% of GDP by 2100. Three studies estimated heat-related healthcare expenses from occupational injuries with averaged annual costs (US$) exceeding 1 million in Spain, 1 million in Guangzhou, China and 250,000 in Adelaide, Australia. Low- and middle-income countries and countries with warmer climates had greater losses as a proportion of GDP. Greater costs per worker were observed in outdoor industries, medium-sized businesses, amongst males, and workers aged 25–44 years. CONCLUSIONS:The estimated global economic burden of occupational heat stress is substantial. Climate change adaptation and mitigation strategies should be implemented to likely minimize future costs. Further research exploring the relationship between occupational heat stress and related expenses from lost productivity, decreased work efficiency and healthcare, and costs stratified by demographic factors, is warranted. Analyzing heat-attributable occupational costs may guide the development of workplace heat management policies and practices as part of global warming strategies. This article has been published in the journal of Environmental Health. KEYWORDS: workplace, heat stress, cost, climate change, labor productivity

Drought and Heat Stress in Cool-Season Food Legumes in Sub-Tropical Regions: Consequences, Adaptation, and Mitigation Strategies.

Drought and heat stress are two major abiotic stresses that challenge the sustainability of agriculture to a larger extend. The changing and unpredictable climate further aggravates the efforts made by researchers as well as farmers. The stresses during the terminal stage of cool-season food legumes may affect numerous physiological and biochemical reactions that may result in poor yield. The plants possess a good number of adaptative and avoiding mechanisms to sustain the adverse situation. The various agronomic and breeding approaches may help in stress-induced alteration. The physiological and biochemical response of crops to any adverse situation is very important to understand to develop mechanisms and approaches for tolerance in plants. Agronomic approaches like altering the planting time, seed priming, foliar application of various macro and micro nutrients, and the application of rhizobacteria may help in mitigating the adverse effect of heat and drought stress to some extent. Breeding approaches like trait-based selection, inheritance studies of marker-based selection, genetic approaches using the transcriptome and metabolome may further pave the way to select and develop crops with better heat and drought stress adaptation and mitigation.

Do nitrogen and zinc application alleviate the adverse effect of heat stress on wheat (Triticum aestivum L.)?

Late-season heat stress (LSH) is a limiting factor for wheat production. Besides, low zinc and poor protein diet usually is a problem in low-income countries. The primary calorie source in such countries is prepared from bread. This study aims to mitigate heat stress by zinc and nitrogen application and improve zinc and protein content in wheat grain. We did the field experiments as a split-split-plot based on a randomized complete block design with four replications to assess zinc and nitrogen’s possible mitigation effect on LSH and protein and zinc enrichment of wheat grain during two years. Factors included LSH by delay in planting date (optimum, late, and very late) as the main plot, nitrogen (0, 75, 150, and 225 kg ha–1) in subplots, and zinc (0, 10, and 20 kg ha–1) as sub-subplots. We measured yield, yield components, physiological traits, zinc, and protein contents in the grain. Results showed that the highest relative water content and cell-membrane thermal stability were attained at the optimum planting date, 150 kg N ha–1 and 20 kg Zn ha–1. The maximum chlorophyll a and carotenoids contents in wheat cells were recorded in the optimum planting date, 225 kg N ha–1, and 20 kg Zn ha–1. Heat stress reduced the grain yield. In the second year of the experiment, the grain number per unit area was more than that of the first year; however, the highest grain yield was achieved in the first year owing to the higher mean grain weight. Nitrogen application decreased the adverse effects of heat stress on grain yield by increasing the grain number. Zinc application diminished the adverse effects of heat stress by increasing the mean grain weight. The adverse impact of the LSH on grain yield was more than that of biological yield. Heat stress reduced the hectolitre weight and zinc content of the grain. Meanwhile, it increased grain protein. In general, under LSH, the application of 225 kg N ha–1 and 20 kg Zn ha–1 can reduce the adverse effects of heat on the grain quality and quantity.

Identification and characterization of genes responsive to drought and heat stress in rice (Oryza sativa L.)

Rice is considered as a major source of food for most people worldwide. Global rice production is under threat as a result of adverse effects of heat and drought stress. It is therefore necessary to safeguard its sustainable production. This study was carried out to characterize differentially expressed genes (DEGs) under both drought and heat stresses in rice. 1001 DEGs were determined to show up-regulation under heat and drought stresses, while 1690 DEGs were commonly down-regulated. Functional classification analysis generated 22 and 37 related gene groups from the commonly up-regulated and down-regulated genes respectively. Functional characterization revealed 38.1% and 45.2% DEGs annotating for Biological Process, 53.2% and 59.2% DEGs were for Cellular Components and 54.8% and 52.4% DEGs were for Molecular Function in the up and down commonly regulated DEGs respectively. KEGG analysis demonstrated that most of the up-regulated DEGs were particularly enriched in metabolic pathways and in the biosynthesis of secondary metabolites, while the down regulated genes were mostly enriched in pathways involving ribosomes, and in purine and pyrimidine metabolisms. These results could be helpful in further analysis and understanding of heat and drought stress tolerance in rice.

Screening of wheat germplasm for terminal heat tolerance under hyper-arid conditions

Due to intensive cropping system, late planting of wheat is very common which causes plants to suffer due to terminal heat stress. To adapt and mitigate the adverse effect of heat on wheat, researchers want to develop heat-tolerant wheat genotypes. Therefore, a set of 11 germplasms of wheat was sown in normal period (November 25) as well as in late period (December 25) at Instructional Farm of Swami Keshwanand Rajasthan Agricultural University, Bikaner. Various physiological, gas exchange and yield attributes were measured at different crop growth stages. Results showed that days to anthesis (DTA), relative water content (RWC), membrane stability index (MSI), photosynthetic pigments, photosynthetic rate (A), stomatal conductance (gs), internal CO2 concentration (ci), water use efficiency (WUE) and yield attributes were reduced, whereas transpiration rate (E) was increased under late sown as compared to normal. Most of the physiological and yield characters showed superiority (highest/lowest) in germplasm entry no. 26 followed by 43 and 58. Heat susceptibility index (HSI) was the lowest, whereas chlorophyll stability (CSI) and heat tolerance index (HTI) were the highest recorded in entry 26 followed by 43. Heat-tolerant germplasm could be selected on the basis of high RWC, MSI, photosynthetic pigments, CSI, A, gs, ci, WUE, yield components and HTI, and low E and HSI. In the present investigation, entry no. 26 (IC279317), 43 (IC335971) and 58 (IC336816) were found the best suited germplasm under heat stress. These germplasms supposed to carry the heat-tolerant genes and may be used for further heat tolerance breeding.

Can Technology Mitigate the Impact of Heat on Labor Productivity? Experimental Evidence from India

This paper analyses the role of technology in reducing heat-induced labor productivity losses. For this, we use a field experiment in India which randomized the use of productivity-augmenting digital mode versus classic paper-and-pen mode for conducting 2000 household surveys. Combining this experimentally induced variation in survey mode with day-to-day variation in temperature, we estimate the impact of survey mode on surveyor productivity as temperature rises. We find that as temperature rises and working conditions start to deteriorate, using digital-mode results in 5 percent higher surveyor-productivity compared to paper surveys. These relative productivity gains are mainly concentrated in extremely hot days - where the adverse impact of heat is likely at its peak. Further analysis shows that these impacts are not driven by differences in effort of surveyors or differences in the characteristics of respondents, thereby pointing to the role of technology in reducing the adverse effects of heat.

Improving brain power by applying a cool TRPM8 receptor agonist to the eyelid margin

Heat impairs human learning and work output when environmental temperatures increase from 18 °C → 25+°C. The hypothesis here is that if the localized, ambient milieu around the upper eyelid margin is perceived as being ~15 °C in coolness, then the adverse effects of heat can be attenuated. This is achieved by topical wipe of a solution to the closed eyelid skin above the eyelashes. The receptor target is TRPM8, an integral membrane protein that transduces the sense of coolness/cold to the central nervous system. The wipe solution contains a TRPM8 agonist called cryosim-3 (1-diisopropylphosphorylnonane) at 1–3 mg/mL in water and designed for delivery to the eyelid margin. Other sensory systems negatively affected by heat, such as the surfaces of the nasal cavity, can also be treated with the TRPM8 agonist as an adjunct to relieve discomfort from the heat.

Mitigation of Heat Stress in Solanum lycopersicum L. by ACC-deaminase and Exopolysaccharide Producing Bacillus cereus: Effects on Biochemical Profiling

Soil microorganisms might be assessed for their capabilities of plant growth promotion in order to identify heat tolerant strategies for crop production. The planned study was conducted to determine the potential of heat tolerant plant growth promoting rhizobacteria (PGPR) in mitigating heat stress effects in tomato. Bacillus cereus was evaluated for plant growth promoting activities and assessed for 1-aminocyclopropane-1-carboxylate (ACC-deaminase) (0.76–C0.9 μM/mg protein/h), and exopolysaccharide (0.66–C0.91 mg/mL) under normal and heat stressed conditions. Plant growth regulators were evaluated through High Performance Liquid Chromatography. Bacterial inoculation effects on important physiological and biochemical parameters were evaluated under normal and heat stressed conditions in growth chamber. The morphological-physiological traits significantly revealed drastic effects on both of un-inoculated tomato varieties under heat stress conditions. Bacterial augmentation significantly promoted shoot, root length, leaf surface area, fresh and dry weight. Heat stress enhanced extracellular polymeric substances (EPS) production and cleavage of ACC into a-ketobutyrate and ammonia due to ACC-deaminase producing bacteria that significantly reduced the adverse effects of heat on tomato growth. In conclusion, the applied plant growth promoting rhizobacteria (PGPR) bacterial strain proved as potential candidate for improving tomato crop growing under heat stressed conditions. However, it is highly suggested to validate the current results by conducting field trials.

Exogenous Selenium-Instigated Physiochemical Transformations Impart Terminal Heat Tolerance in Bt Cotton

High temperature during reproductive stages of cotton is a major constraint to achieve potential yield of cotton. The aim of the present study was to determine comparative thermo-sensitivity of squaring and flowering, to optimize exogenous selenium for heat-stressed cotton, and to explore correlation among physiochemical and morphological attributes. The experiment was conducted during 2013 and repeated during 2014. The experiment was laid out in randomized complete block design under split plot arrangement and replicated thrice. Treatments were comprised of heat stress (H0 = no heat imposition; H1 = heat imposition at squaring; and H2 = heat imposition at flowering) in main plot and varying foliar selenium concentrations (Se0 = water spray/control; Se50 = 50; Se100 = 100; and Se150 = 150 mg L-1 selenium) in split plot. Significantly, more antioxidants, chlorophyll contents, water relation attributes, seed cotton yield, and lesser hydrogen peroxide were recorded with 150 mg L-1 foliar selenium compared with other concentrations under H0. While under H1 and H2, statistically similar and significantly more antioxidants, chlorophyll contents, water relation attributes, seed cotton yield, and lesser hydrogen peroxide were observed for 100 and 150 mg L-1 selenium compared with other selenium concentrations. Conclusively, H2 proved more thermolabile compared with H1, and application of 150 mg L-1 foliar selenium effectively alleviated adverse effects of heat. Moreover, we observed strong and significant associations of all physiochemical attributes with seed cotton yield.

Heat stress responses in a large set of winter wheat cultivars (Triticum aestivum L.) depend on the timing and duration of stress.

The adverse effects of heat on plant yield strongly depend on its duration and the phenological stage of the crops when the heat occurs. To clarify the effects of these two aspects of heat stress, systematic research was conducted under controlled conditions on 101 wheat cultivars of various geographic origin. Different durations of heat stress (5, 10 and 15 days) were applied starting from three developmental stages (ZD49: booting stage, ZD59: heading, ZD72: 6th day after heading). Various morphological, yield-related traits and physiological parameters were measured to determine the stress response patterns of the wheat genotypes under combinations of the duration and the timing of heat stress. Phenological timing significantly influenced the thousand-kernel weight and reproductive tiller number. The duration of heat stress was the most significant component in determining both seed number and seed weight, as well as the grain yield consequently, explaining 51.6% of its phenotypic variance. Irrespective of the developmental phase, the yield-related traits gradually deteriorated over time, and even a 5-day heat stress was sufficient to cause significant reductions. ZD59 was significantly more sensitive to heat than either ZD49 or ZD72. The photosynthetic activity of the flag leaf was mostly determined by heat stress duration. No significant associations were noted between physiological parameters and heat stress response as measured by grain yield. Significant differences were observed between the wheat genotypes in heat stress responses, which varied greatly with developmental phase. Based on the grain yield across developmental phases and heat stress treatments, eight major response groups of wheat genotypes could be identified, and among them, three clusters were the most heat-tolerant. These cultivars are currently included in crossing schemes, partially for the identification of the genetic determinants of heat stress response and partially for the development of new wheat varieties with better heat tolerance.

Experimental identification and thermodynamic analysis of ammonia sorption equilibrium characteristics on halide salts

Solid–gas chemisorption based on metal ammine complexes is a kind of promising energy-saving and environment-friendly technology for various thermal engineering applications such as chemical heat pump, thermochemical energy storage, chemisorption refrigeration, etc. The accurate thermodynamic parameters of ammonia sorption on halide salts can allow a significant theoretical and experimental study on a solid–gas chemisorption system using halide salt–ammonia sorption working pairs. In this study, the thermodynamic properties of chemisorption between strontium chloride (SrCl2) and ammonia is firstly investigated by developing a facile methodology for sorption equilibrium measurement. The facile methodology involves the fabrication of incompact composite sorbent of expanded graphite/SrCl2 with high porosity and an optimized temperature-controlling method so as to weaken the adverse effect of heat and mass transfer on chemisorption and realize the chemical equilibrium and thermal quasi-equilibrium during the isobaric measurement process. Through the experimental measurement, the stoichiometric equations of chemisorption between SrCl2 and NH3 are updated, and thermodynamic parameters including reaction enthalpy, reaction entropy and hysteresis are identified. Similarly, the thermodynamic characteristics of chemisorption between ammonia and halide salts BaCl2, SrBr2, and MnCl2 are also investigated. The facile methodology is proved available for measuring the ammonia sorption equilibrium characteristics on halide salts. At last, the working performance of a cascade thermochemical energy storage system using four halides salts is analyzed based on the obtained thermodynamic parameters.

Medical diagnoses of heat wave-related hospital admissions in older adults

Heat waves have been associated with adverse human health effects, including higher rates of all-cause and cardiovascular mortality, and these health effects may be exacerbated under continued climate change. However, specific causes of hospitalizations associated with heat waves have not been characterized on a national scale. We systematically estimated the risks of cause-specific hospitalizations during heat waves in a national cohort of 23.7 million Medicare enrollees residing in 1943 U.S. counties during 1999–2010. Heat waves were defined as ≥2 consecutive days exceeding the county's 99th percentile of daily temperatures, and were matched to non-heat wave periods by county and week. We considered 50 outcomes from broad disease groups previously associated with heat wave-related hospitalizations, and estimated cause-specific relative risks (RRs) of hospital admissions on heat wave days. We identified 11 diagnoses with a higher admission risk on heat wave days, with heat stroke and sunstroke having the highest risk (RR = 22.5, [95% CI 14.9–34.2]). Other diseases with elevated risks included fluid and electrolyte disorders [(Hyperosmolality RR = 1.4, [95% CI 1.1–1.3]; Hypoosmolaltiy RR = 1.2, [95% CI 1.1–1.3])] and acute kidney failure (RR = 1.1, [95% CI 1.1–1.2]). These risks tended to be higher under more severe heat wave events. In addition, risks were higher among adults in the oldest (≥85) category (reference: 65–74) for volume depletion and heat exhaustion. Several causes of hospitalization identified are preventable, and public health interventions, including early warning systems and plans targeting risk factors for these illnesses, could reduce adverse effects of heat in the present and under climate change.

The Impact of Nonthermal Technologies on the Microbiological Quality of Juices: A Review.

Fruit and vegetable juices are rich sources of nutrients that support microbiological growth and ultimately undergo rapid deterioration of safety and quality. The loss of nutritional quality of juices due to intensive thermal processing is a major problem encountered during the treatment of commercially preserved liquid foods. Conventional thermal processing technologies inactivate microorganisms and enzymes and extend the shelf life of foods but exert negative effects on nutritional and organoleptic properties of juices, for example, a loss of vitamins, of a desirable flavor, and of bioactive compounds and development of different sensory profiles as a result of heating. Nonthermal technologies including ultrasonication, a pulsed electric field, high-pressure processing, irradiation, and their combinations are suitable alternatives for achieving the same preservation effect without the adverse effects of heat on the quality of juices and meet consumer demand for clean-label, safe, and wholesome products without compromising their nutritional properties.

Comparative transcriptional profiling of Gracilariopsis lemaneiformis in response to salicylic acid- and methyl jasmonate-mediated heat resistance.

Culturing the economically important macroalga Gracilariopsis lemaneiformis (Rhodophyta) is limited due to the high temperatures in the summertime on the southern Chinese coast. Previous studies have demonstrated that two phytohormones, salicylic acid (SA) and methyl jasmonate (MJ), can alleviate the adverse effects of high-temperature stress on Gp. lemaneiformis. To elucidate the molecular mechanisms underlying SA- and MJ-mediated heat tolerance, we performed comprehensive analyses of transcriptome-wide gene expression profiles using RNA sequencing (RNA-seq) technology. A total of 14,644 unigenes were assembled, and 10,501 unigenes (71.71%) were annotated to the reference databases. In the SA, MJ and SA/MJ treatment groups, 519, 830, and 974 differentially expressed unigenes were detected, respectively. Unigenes related to photosynthesis and glycometabolism were enriched by SA, while unigenes associated with glycometabolism, protein synthesis, heat shock and signal transduction were increased by MJ. A crosstalk analysis revealed that 216 genes were synergistically regulated, while 18 genes were antagonistically regulated by SA and MJ. The results indicated that the two phytohormones could mitigate the adverse effects of heat on multiple pathways, and they predominantly acted synergistically to resist heat stress. These results will provide new insights into how SA and MJ modulate the molecular mechanisms that counteract heat stress in algae.

Diabetes and temperature

Diabetes and temperature

Modification of Heat-Related Mortality in an Elderly Urban Population by Vegetation (Urban Green) and Proximity to Water (Urban Blue): Evidence from Lisbon, Portugal.

Background:Urban populations are highly vulnerable to the adverse effects of heat, with heat-related mortality showing intra-urban variations that are likely due to differences in urban characteristics and socioeconomic status.Objectives:We investigated the influence of urban green and urban blue, that is, urban vegetation and water bodies, on heat-related excess mortality in the elderly > 65 years old in Lisbon, Portugal, between 1998 and 2008.Methods:We used remotely sensed data and geographic information to determine the amount of urban vegetation and the distance to bodies of water (the Atlantic Ocean and the Tagus Estuary). Poisson generalized additive models were fitted, allowing for the interaction between equivalent temperature [universal thermal climate index (UTCI)] and quartiles of urban greenness [classified using the Normalized Difference Vegetation Index (NDVI)] and proximity to water (≤ 4 km vs. > 4 km), while adjusting for potential confounders.Results:The association between mortality and a 1°C increase in UTCI above the 99th percentile (24.8°C) was stronger for areas in the lowest NDVI quartile (14.7% higher; 95% CI: 1.9, 17.5%) than for areas in the highest quartile (3.0%; 95% CI: 2.0, 4.0%). In areas > 4 km from water, a 1°C increase in UTCI above the 99th percentile was associated with a 7.1% increase in mortality (95% CI: 6.2, 8.1%), whereas in areas ≤ 4 km from water, the estimated increase in mortality was only 2.1% (95% CI: 1.2, 3.0%).Conclusions:Urban green and blue appeared to have a mitigating effect on heat-related mortality in the elderly population in Lisbon. Increasing the amount of vegetation may be a good strategy to counteract the adverse effects of heat in urban areas. Our findings also suggest potential benefits of urban blue that may be present several kilometers from a body of water.Citation:Burkart K, Meier F, Schneider A, Breitner S, Canário P, Alcoforado MJ, Scherer D, Endlicher W. 2016. Modification of heat-related mortality in an elderly urban population by vegetation (urban green) and proximity to water (urban blue): evidence from Lisbon, Portugal. Environ Health Perspect 124:927–934; http://dx.doi.org/10.1289/ehp.1409529

Prevention of adverse heat effects on elderly – a qualitative study among GPs in Germany

Prevention of adverse heat effects on elderly – a qualitative study among GPs in Germany

An adaptation index to high summer heat associated with adverse health impacts in deprived neighborhoods

Socially and materially disadvantaged urban areas present a group of factors strongly correlated with high heat and humidity adverse health effects, particularly in densely populated cities where the heat island effect extends over large areas. This paper presents an adaptation index to high summer heat whose validity was tested by correlating it with self-reported adverse health impacts to heat. The data comes from a 2011 cross-sectional study conducted in the most deprived areas in 9 cities of 100,000 or more inhabitants in Quebec (Canada). In total, 3,485 people were interviewed at home. An index of various behavioral adaptations was developed using a Multiple Correspondence Analysis. This individual-level adaptation index summarizes a range of 14 easy-to-use and energy-efficient solutions for cooling off or protecting oneself against the sun, both at home and in other places, whether indoors or out. In addition, it shows that adaptation to heat goes beyond air conditioning in the home. People who experience adverse effects of heat on their health tend to adopt more of the behaviors measured by the index than those perceiving little or none, regardless of their age group or presence of air conditioning at home. Monitoring and improving this index over time and in several populations and contexts would establish a significant milestone for adaptation in health promotion and prevention.

Do wind turbines cause adverse heat effects? A review of the evidence

There is a continuing debate about the veracity of AHE in the environs of WT. Proponents claim there is insufficient evidence to support the existence of direct AHE and therefore WT are safe to erect near human habitation. The international regulations governing WT placement are highly variable but generally a setback of at least 350 m (WHO 500m) and a noise limit of 40 dBA are recommended. Nonetheless there is mounting evidence that AHE are in fact occurring. In the 1980s, N D Kelley produced evidence of direct causation of AHE, especially sleep disturbance, from downwind WT, which was attributable to impulsive infrasound and low frequency noise. Subsequently, there has emerged further evidence regarding upwind WT that satisfies the nine Bradford Hill criteria. The presentation will define AHE and address each Braford Hill criterion.