Climate change, workplace heat exposure, and occupational health and productivity in Central America

Climate change is increasing heat exposure in places such as Central America, a tropical region with generally hot/humid conditions. Working people are at particular risk of heat stress because of the intrabody heat production caused by physical labor. This article aims to describe the risks of occupational heat exposure on health and productivity in Central America, and to make tentative estimates of the impact of ongoing climate change on these risks. A review of relevant literature and estimation of the heat exposure variable wet bulb globe temperature (WBGT) in different locations within the region were used to estimate the effects. We found that heat stress at work is a real threat. Literature from Central America and heat exposure estimates show that some workers are already at risk under current conditions. These conditions will likely worsen with climate change, demonstrating the need to create solutions that will protect worker health and productivity.     

Climate Change,Workplace Heat Exposure,and Occupational Health and Productivity in Central America

Abstract

Climate change is increasing heat exposure in places such as Central America, a tropical region with generally hot/humid conditions. Working people are at particular risk of heat stress because of the intrabody heat production caused by physical labor. This article aims to describe the risks of occupational heat exposure on health and productivity in Central America, and to make tentative estimates of the impact of ongoing climate change on these risks. A review of relevant literature and estimation of the heat exposure variable wet bulb globe temperature (WBGT) in different locations within the region were used to estimate the effects. We found that heat stress at work is a real threat. Literature from Central America and heat exposure estimates show that some workers are already at risk under current conditions. These conditions will likely worsen with climate change, demonstrating the need to create solutions that will protect worker health and productivity.     

Calculating Workplace WBGT from Meteorological Data: A Tool for Climate Change Assessment

The WBGT heat stress index has been well tested under a variety of climatic conditions and quantitative links have been established between WBGT and the work-rest cycles needed to prevent heat stress effects at the workplace. While there are more specific methods based on individual physiological measurements to determine heat strain in an individual worker, the WBGT index is used in international and national standards to specify workplace heat stress risks. In order to assess time trends of occupational heat exposure at population level, weather station records or climate modelling are the most widely available data sources. The prescribed method to measure WBGT requires special equipment which is not used at weather stations. We compared published methods to calculate outdoor and indoor WBGT from standard climate data, such as air temperature, dew point temperature, wind speed and solar radiation. Specific criteria for recommending a method were developed and original measurements were used to evaluate the different methods. We recommend the method of Liljegren et al. (2008) for calculating outdoor WBGT and the method by Bernard et al. (1999) for indoor WBGT when estimating climate change impacts on occupational heat stress at a population level.     

Mortality surveillance and occupational hazards: the Solutia mortality experience 1980-94

OBJECTIVES—Several investigators argue that company wide mortalities for recent workers allow early identification of potential workplace hazards. Mortalities for recent workers were compared with published studies of workers with specific exposures in the same company to find whether mortality surveillance results could be used to identify previously unknown health effects from workplace hazards.
METHODS—Relative risks for causes of death in published substance specific studies at the plants were compared with the relative risks in the mortality surveillance of workers 20 or more years after first being employed.
RESULTS—As reported by other companies, low mortalities were found among workers in the mortality surveillance. The mortality surveillance reports often found no increased risk of disease at plants in which substance specific studies had found no effects. However, disease specific relative risks were not found by the mortality surveillance predictions of relative risks in the substance specific studies with increased risk.
CONCLUSION—Mortality surveillance is of limited use for identifying health effects from past workplace exposures to specific materials. The healthy worker and survivor effects, the failure to identify subsets of workers exposed to potentially toxic substances, the typically long induction period between exposure and disease, and the inability of recent mortality levels to reflect historical conditions all may make it difficult to use mortality surveillance to identify workplace hazards. Combining mortality surveillance with studies of workers with potentially toxic exposures helps identify occupational hazards.


Keywords: mortality surveillance; occupational cancer; bladder cancer; leukaemia     

Greek employee awareness of carcinogenic exposure

BACKGROUND: Occupational risk factors contribute significantly to the development of lung cancer; however, little is known about the extent to which employees are informed of occupational exposure to carcinogenic substances. METHODS: Through a case-control study, we estimated the level of awareness among Greek employees potentially exposed to known carcinogenic substances within various occupational settings. RESULTS: Only 6.6% of men (n = 482) employed in occupations with potential exposure to carcinogenic substances were aware of such occupational exposures. Age, education, and residence were significantly associated with awareness. Employees having at least a secondary level of education were 3.5 times more aware than those having at most 6 years of educational training. CONCLUSIONS: Assessing awareness among workers potentially exposed to occupational risk factors and promoting occupational health education are important steps for increasing health and safety at the workplace.     

Effects of informing workers of their health risks from exposure to toxic materials

This study compared the mental health, attitudes, and smoking behaviors of 133 workers who had been informed of health risks from exposure to toxic materials on the job with 137 workers who worked in similar conditions but who had not been told that their health was at risk because of exposure to toxic materials. The informed workers reported more health problems than controls, but there were no significant differences between the informed and uninformed groups in mental health, attitudes toward health hazards in or outside of the workplace, or in smoking rates. Ninety percent of all respondents felt that exposed workers definitely should be told of their health risks. These findings indicate little psychological risk from informing workers about their risks because of exposure to toxic substances and a strong desire on the part of workers to be informed.     

The influence of workplace environment on lung function of flour mill workers in Jalgaon urban center

The workplace environment affects the health of workers. Unhygienic conditions are observed in the workplace environment of flour mills as fine organic flour dust gets airborne in the indoor environment of the flour mills. The present work was undertaken to study the health problems related to the workplace environment of flour mill workers. The results show that flour mill workers are receiving a heavy dose (average exposure concentration, 624 microg/m3) of flour dust. To determine the impact of flour dust on the lung function of the workers spirometric analysis was conducted. Significant declines in forced vital capacity (FVC), peak expiratory flow rate (PEFR) and forced expiratory volume in one second (FEV1) were observed in the flour mill workers as compared to expected values. This study reveals reduced lung efficiency of flour mill workers due to excessive exposure to fine organic dust prevalent in the workplace environment. The impairment in lung efficiency was increased with duration of exposure in the flour mill workers. The analysis of questionnaires used to generate information on self-reported problems reveals that most of the workers were suffering from asthma and respiratory problems. Furthermore, the data shows that 42% of the flour mill workers were having shortness of breath problems, 34% of workers were having frequent coughing, and 19% workers were having respiratory tract irritation. We recommend the compulsory use of personal protective equipment (nose mask) by flour mill workers during working hours. This would help to protect the workers health from the flour dust prevalent in the workplace environment. A regular periodic examination is necessary to measure the impact of particulate matter on the health of the flour mill workers.     

Hearing loss among workers exposed to moderate concentrations of solvents.

OBJECTIVES: It is known that some industrial organic solvents are ototoxic. This study was aimed at evaluating the hearing effects of a mixture of organic solvents alone or in combination with noise on employees in paint and lacquer enterprises. The concentration of solvents was below the occupational exposure limits (OEL) for most of the subjects. METHODS: Altogether 517 subjects were divided into the following three groups: persons with no risk due to noise or organic solvent exposure at the workplace, workers exposed to organic solvents only, and workers exposed to both organic solvents and noise. RESULTS: The relative risk (RR) of hearing loss in the solvent-only exposure group was significantly increased (RR 4.4 and RR 2.8 for noise exposure of < 80 dB-A and < 85 dB-A, respectively) in a wide range of frequencies (2-8 kHz). No additional risk in the solvent + noise exposure group was found (RR 2.8). Hearing thresholds were significantly poorer in a wide range of frequencies (1-8 kHz) for both groups exposed to solvents, when compared with the reference group. The mean hearing thresholds at frequencies of 2-4 kHz were poorer for workers exposed to solvents + noise than for the solvent-only group; this finding suggests an additional effect for noise. However, there was no correlation between hearing loss and the extent of solvent exposure. CONCLUSIONS: The results indicate that occupational organic solvent exposure at moderate concentrations increases the risk of hearing loss, and the ototoxic effects should be considered when the health effects of exposed workers are monitored.     

Social connection as a public health adaptation to extreme heat events

Climate change is an increasingly important public health issue, reflected in morbidity and mortality outcomes during extreme heat events. At the same time, the harms of social isolation with respect to a wide range of health outcomes are becoming better understood. Given that older adults are at higher risk during hot weather and at higher risk of social isolation, they are among those at highest risk for adverse impacts of extreme heat events. While specific strategies to reduce heat exposure have been described in the literature and promoted in public health practice, these may not be readily available to socially isolated older adults. As such, it is crucial to identify key approaches to address risk due to social isolation in the aging population, and to acknowledge their limitations and barriers. Interventions rooted in social connection, a concept widely applied in interventions for public health and social well-being, should be applied as a tool for adaptation to extreme heat events.     

Female Farmworkers’ Perceptions of Heat-Related Illness and Pregnancy Health

ABSTRACT

Although agricultural workers have elevated risks of heat-related illnesses (HRI), pregnant farmworkers exposed to extreme heat face additional health risk, including poor pregnancy health and birth outcomes. Qualitative data from five focus groups with 35 female Hispanic and Haitian nursery and fernery workers provide details about the women's perceptions of HRI and pregnancy. Participants believe that heat exposure can adversely affect general, pregnancy, and fetal health, yet feel they lack control over workplace conditions and that they lack training about these specific risks. These data are being used to develop culturally appropriate educational materials emphasizing health promoting and protective behaviors during pregnancy.     

Relationship between work-related accidents and hot weather conditions in Tuscany (central Italy)

Nowadays, no studies have been published on the relationship between meteorological conditions and work-related mortality and morbidity in Italy. The aim of this study was to evaluate the relationship between hot weather conditions and hospital admissions due to work-related accidents in Tuscany (central Italy) over the period 1998-2003. Apparent temperature (AT) values were calculated to evaluate human weather discomfort due to hot conditions and then tested for work accident differences using non-parametric procedures. Present findings showed that hot weather conditions might represent a risk factor for work-related accidents in Italy during summer. In particular early warming days during June, characterized by heat discomfort, are less tolerated by workers than warming days of the following summer months. The peak of work-related accidents occurred on days characterized by high, but not extreme, thermal conditions. Workers maybe change their behaviour when heat stress increases, reducing risks by adopting preventive measures. Results suggested that days with an average daytime AT value ranged between 24.8 degrees C and 27.5 degrees C were at the highest risk of work-related accidents. In conclusion, present findings might represent the first step for the development of a watch/warning system for workers that might be used by employers for planning work activities.     

The European Directive 2002/44/CE on the protection of workers from risks resulting from mechanical vibration

This paper provides comments on the European Directive 2002/44/CE of 25 June 2002 on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (vibration) (sixteenth individual Directive according to Article 16(1) of Directive 89/291/EEC). The European Directive on mechanical vibration was published in the Official Journal of the European Communities L 177/13 on 6 July 2002. The Directive includes the definitions of hand-arm vibration and whole-body vibration, establishes the daily exposure limit values and action values for mechanical vibration, and gives provisions related to (i) determination and assessment of risks, (ii) measures aimed at avoiding or reducing exposure, (iii) information, training, consultation and participation of workers, (iv) health surveillance of the exposed workers, and (v) derogations and transitional periods for the implementation of the obligations of employers when the daily exposure limit values are exceeded. The author discusses the strong link which exists between the assessment of risk due to vibration exposure at the workplace and the health surveillance of the exposed workers. The occupational health physician, as a specialist with expertise in human factors and in the early detection of vibration-related adverse health effects, will have an important role in the assessment of risks arising from mechanical vibration in order to implement an effective health surveillance of the exposed workers. The Member States must bring into force the requirements of the Directive no later than 6 July 2005.     

Benzene exposure among auto-repair workers from workplace ambience: A pioneer study from Pakistan

Objectives

In Pakistan, the reports on benzene exposure among workers in chemical industries are almost non-existing due to limited research work in the field of exposure science. This study aimed to investigate such exposure in a widely adopted occupation in Rawalpindi city.

Material and Methods

In this cross-sectional study, 60 blood samples (N = 20/group) of mechanics (MCs), spray painters (PNs) and control participants (CN) were analyzed. The socio-economic and demographic information of workers and that of workplaces was documented using a short questionnaire.

Results

We identified that the workers in spray-painting occupation are highly at risk of benzene exposure. The results showed that PNs were more at risk of exposure to benzene than MCs, and this exposure was significantly correlated with long working hours (r = 0.68, p < 0.001). Moreover, there are several limitations in workplace setups, which need to be addressed in order to mitigate workers health risk in this occupation. In addition to the reckless use of chemicals, other identified predictors of exposure included active and passive smoking, poor workplace hygiene and substandard ventilation.

Conclusions

To mitigate workplace exposure, it is necessary to reduce working hours and encourage regular use of self-protective equipments and adoption of proper hygiene in chemical workplaces.     

Heat-related deaths among crop workers--United States, 1992--2006

Workers employed in outdoor occupations such as farming are exposed to hot and humid environments that put them at risk for heat-related illness or death. This report describes one such death and summarizes heat-related fatalities among crop production workers in the United States during 1992--2006. During this 15-year period, 423 workers in agricultural and nonagricultural industries were reported to have died from exposure to environmental heat; 68 (16%) of these workers were engaged in crop production or support activities for crop production. The heat-related average annual death rate for these crop workers was 0.39 per 100,000 workers, compared with 0.02 for all U.S. civilian workers. Data aggregated into 5-year periods indicated that heat-related death rates among crop workers might be increasing; however, trend analysis did not indicate a statistically significant increase. Prevention of heat-related deaths among crop workers requires educating employers and workers on the hazards of working in hot environments, including recognition of heat-related illness symptoms, and implementing appropriate heat stress management measures.     

At Work in the Woods: Occupational Hazards of Harvesting Non-Timber Forest Products in the Pacific Northwest

ABSTRACT

Harvesting timber for lumber produces is among the most dangerous occupations in the United States. While not exhaustive, the literature on these dangers is substantial. However, several other smaller harvesting forest based industries put workers at risk in unique ways. Relatively little research has been published on these activities, but preliminary exploratory research, summarized here, suggests that besides the risks inherent in being in the forest, workers face some unique workplace risks, the frequency and consequences of which are augmented by the social determinants that characterize the workforce. This paper provides a brief overview of the workplace safety risks to forest green and mushroom harvesters and cedar block cutters in the Northwest. We also point out the social characteristics of these workforces that potentially aggravate these risks and the health impacts therefrom.     

Beyond dose assessment: using risk with full disclosure of uncertainty in public and scientific communication

Evaluations of radiation exposures of workers and the public traditionally focus on assessments of radiation dose, especially annual dose, without explicitly evaluating the health risk associated with those exposures, principally the risk of radiation-induced cancer. When dose is the endpoint of an assessment, opportunities to communicate the significance of exposures are limited to comparisons with dose criteria in regulations, doses due to natural background or medical x-rays, and doses above which a statistically significant increase of disease has been observed in epidemiologic studies. Risk assessment generally addresses the chance (probability) that specific diseases might be induced by past, present, or future exposure. The risk of cancer per unit dose will vary depending on gender, age, exposure type (acute or chronic), and radiation type. It is not uncommon to find that two individuals with the same effective dose will have substantially different risks. Risk assessment has shown, for example, that: (a) medical exposures to computed tomography scans have become a leading source of future risk to the general population, and that the risk would be increased above recently published estimates if the incidence of skin cancer and the increased risk from exposure to x-rays compared with high-energy photons were taken into account; (b) indoor radon is a significant contributor to the baseline risk of lung cancer, particularly among people who have never smoked; and (c) members of the public who were exposed in childhood to I in fallout from atmospheric nuclear weapons tests and were diagnosed with thyroid cancer later in life would frequently meet criteria established for federal compensation of cancers experienced by energy workers and military participants at atmospheric weapons tests. Risk estimation also enables comparisons of impacts of exposures to radiation and chemical carcinogens and other hazards to life and health. Communication of risk with uncertainty is essential for reaching informed consent, whether communicating to a larger community debating the tradeoffs of risks and benefits of an action that involves radiation exposure or communicating at the level of a physician and patient.     

Patterns and predictors of personal protection compliance and workplace hygiene behaviors among workers with elevated blood lead levels in New York State

Despite increasing awareness and significant progress in reducing lead exposure among workers, elevated blood lead levels (BLLs) continue to be an occupational health problem. Little is currently known about the extent of personal protective equipment (PPE) use among lead-exposed workers. We examined the patterns and predictors of consistent PPE use and workplace hygiene behaviors among workers with elevated BLLs using a survey of 1,459 workers with an occupational lead exposure in New York State (NYS). Routine availability of respirators was commonplace, however only approximately half of workers consistently wore PPE while working with lead. Regular access to showers was reported by 41% of workers, but less than a quarter took showers and subsequently changed into clean clothing before leaving work site. Significant predictors of consistent PPE use and good hygiene behaviors were identified. The findings highlight the need for further educational and policy interventions for lead-exposed employees. Increased employer efforts are also required to provide workplace structures and a culture that supports compliance. These include the provision of routine training and hazard communication, provision of appropriate PPE and hygiene facilities, and enforcing its use where necessary.     

Thermal effect of infra-red radiation on the eye: a study based on a model

Cataracts occur frequently among workers who deal with hot material such as molten glass or steel, as a result of exposure to intense infra-red radiation (i.r.) emitted from it. To investigate this hazard, a theoretical model of the human eye being exposed to i.r. was developed, and the temperature distributions within it were calculated. It is suggested that i.r. cataracts in the workplace result from the generation of heat by absorption of i.r. in the cornea and heat conduction to the lens. The threshold i.r. irradiances for cataract formation were determined from the relationship between the incident irradiance and the lens temperature, and were in the range 163-178 mW cm-2 for long-term exposures (greater than about 5 min) under normal conditions. However, these values may be reduced by 50% for workers who perform heavy work at a high ambient temperature. It may be possible to set i.r. exposure limits in the workplace based on these threshold data.     

Hearing impairment among workers exposed to excessive levels of noise in ginning industries

Cotton ginning workers have a risk of hearing loss due to excessive noise levels at the workplace environment. In this study, estimates of typical sound levels prevailing at the workplace environment and its effects on hearing ability of the exposed workers were made among cotton ginning workers. Data on self-reported health status was collected by a questionnaire survey at 10 cotton ginning industries located at Jalgaon district of Maharashtra state, India. The cotton ginning workers were exposed to continuous noise levels between 89 and 106 dBA. The hearing ability of the subjects was accessed by pure tone audiometry. The results of audiometry show mild, moderate and moderately severe degree of hearing impairment among the cotton ginning workers. The data generated during the study show that hearing loss was significantly associated with period of exposure to the workplace noise (P <0.0001). The prevalence of audiometric hearing impairment defined as a threshold average greater than 25 dB hearing level was 96% for binaural low-frequency average, 97% for binaural mid frequency average and 94% for binaural high-frequency average in the cotton ginning workers. We recommend the compulsory use of personal protective equipment like ear plug by the cotton ginning workers at the workplace environment. A regular maintenance of ginning and pressing machineries will avoid the emission of excessive noise at the workplace environment of cotton gins. A regular periodic medical examination is necessary to measure the impact of workplace noise on the health of cotton ginning workers.     

Exposure to shock and vibration and symptoms in workers using impact power tools

In The Netherlands damage to health due to occupational exposure to shock and vibration is seldom reported. A survey was therefore made of the nature, extent and severity of exposure to shock and vibration. This paper presents the results of an epidemiological study, by questionnaire, among workers using impact power tools. Data were collected about exposure time, symptoms and the subjective workload. A prevalence rate of 17% for symptoms of white finger was found. In the logistic regression symptoms of back pain showed an increased prevalence with increasing total time exposed to vibration. This study shows that exposure to vibration due to working with impact power tools, either alone or in combination with ergonomically bad working conditions, probably contributes to these symptoms. An estimate of the population at risk showed that over 30,000 workers in The Netherlands who use impact power tools are exposed to a vibration intensity of 10-40 m s-2. This intensity exceeds the standards advocated in draft standards in the U.K. (BSI, 1987) and U.S.A. (ACGIH, 1984). The results also provide evidence that in The Netherlands exposure to hand-arm vibration damages health. It is suggested that damage to health due to occupational exposure to vibration is underestimated by the Dutch occupational health services. It was concluded that more investigation is needed to evaluate the precise nature of occupational exposure to vibration in order to provide a basis for its reduction or elimination.