Showing papers in "Industrial Health in 2006"

Thermal Comfort and the Heat Stress Indices

Abstract: Thermal stress is an important factor in many industrial situations, athletic events and military scenarios. It can seriously affect the productivity and the health of the individual and diminish tolerance to other environmental hazards. However, the assessment of the thermal stress and the translation of the stress in terms of physiological and psychological strain is complex. For over a century attempts have been made to construct an index, which will describe heat stress satisfactorily. The many indices that have been suggested can be categorized into one of three groups: "rational indices", "empirical indices", or "direct indices". The first 2 groups are sophisticated indices, which integrate environmental and physiological variables; they are difficult to calculate and are not feasible for daily use. The latter group comprises of simple indices, which are based on the measurement of basic environmental variables. In this group 2 indices are in use for over four decades: the "wet-bulb globe temperature" (WBGT) index and the "discomfort index" (DI). The following review summarizes the current knowledge on thermal indices and their correlates to thermal sensation and comfort. With the present knowledge it is suggested to adopt the DI as a universal heat stress index.

A review of the literature on preventive occupational health and safety activities in small enterprises

Abstract: The scientific literature regarding preventive occupational health and safety activities in small enterprises has been reviewed in order to identify effective preventive approaches and to develop a future research strategy. During the last couple of years, there has been a significant increase in the number of studies of small enterprises, but the research community is scattered between many different disciplines and institutions. There is a lack of evaluation of intervention studies, both in terms of effect and practical applicability. However, there is sufficiently strong evidence to conclude that employees of small enterprises are subject to higher risks than the employees of larger ones, and that small enterprises have difficulties in controlling risk. The most effective preventive approaches seem to be simple and low cost solutions, disseminated through personal contact. It is important to develop future intervention research strategies which study the complete intervention system: from the intermediaries through dissemination methods to the resulting preventive activities of the small enterprises.

Heat stress standard ISO 7243 and its global application

Abstract: This paper presents heat stress Standard ISO 7243, which is based upon the wet bulb globe temperature index (WBGT), and considers its suitability for use worldwide. The origins of the WBGT index are considered and how it is used in ISO 7243 and across the world as a simple index for monitoring and assessing hot environments. The standard (and index) has validity, reliability and usability. It is limited in application by consideration of estimating metabolic heat and the effects of clothing. Use of the standard also requires interpretation in terms of how it is used. Management systems, involving risk assessments, that take account of context and culture, are required to ensure successful use of the standard and global applicability. For use outdoors, a WBGT equation that includes solar absorptivity is recommended. A 'clothed WBGT' is proposed to account for the effects of clothing. It is concluded that as a simple assessment method, ISO 7243 has face validity and within limits is applicable worldwide.

Possible broad impacts of long work hours

Abstract: The paper summarizes research linking long work hours to a wide range of risks to workers, families, employers, and the community. The risks are theorized to stem from less time to recover from work, longer exposure to workplace hazards, and less time to attend to non-work responsibilities. Risks to workers include sleep deprivation, poor recovery from work, decrements in neuro-cognitive and physiological functioning, illnesses, adverse reproductive outcomes, and injuries. Risks to families include delayed marriages and child bearing, and obesity in children. Risks to employers include reduced productivity and increases in workers errors. Mistakes by fatigued workers have broad reaching impacts to the community: medical errors, automobile crashes with other drivers on the road, and industrial disasters that damage the environment.

Health Problems due to Long Working Hours in Japan: Working Hours, Workers' Compensation (Karoshi), and Preventive Measures

Abstract: Late in the 1970s, serious social concern over health problems due to long working hours has arisen in Japan. This report briefly summarizes the Japanese circumstances about long working hours and what the Government has achieved so far. The national statistics show that more than 6 million people worked for 60 h or more per week during years 2000 and 2004. Approximately three hundred cases of brain and heart diseases were recognized as labour accidents resulting from overwork (Karoshi) by the Ministry of Health, Labour and Welfare (MHLW) between 2002 and 2005. Consequently, the MHLW has been working to establish a more appropriate compensation system for Karoshi, as well as preventive measures for overwork related health problems. In 2001, the MHLW set the standards for clearly recognizing Karoshi in association with the amount of overtime working hours. These standards were based on the results of a literature review and medical examinations indicating a relationship between overwork and brain and heart diseases. In 2002, the MHLW launched the program for the prevention of health impairment due to overwork, and in 2005 the health guidance through an interview by a doctor for overworked workers has been enacted as law. Long working hours are controversial issues because of conflicts between health, safety, work-life balance, and productivity. It is obvious that we need to continue research regarding the impact on worker health and the management of long working hours.

Protective clothing in hot environments.

Abstract: The high level of protection required by personal protective clothing (PPC) severely impedes heat exchange by sweat evaporation. As a result work associated with wearing PPC, particularly in hot environments, implies considerable physiological strain and may render workers exhausted in a short time. Recent development of algorithms for describing the heat transfer, accounting for pumping and wind effects, comprises improvement of the prediction of thermal stress. Realistic corrections can then be made to the available measures of thermal insulation and evaporative resistance of a given clothing ensemble. Currently this information is incorporated in international standards for assessment of thermal environments. Factors, such as directional radiation and wetting of layers, were studied in a recently completed EU research project. The development of advanced thermal manikins and measurement procedures should provide better measures for predictive models. As with all methods and models, the results need validation in realistic wear trials in order to prove their relevance and accuracy.

Challenges to temperature regulation when working in hot environments.

Abstract: The focus of this review is upon acute exposure to hot environments and the accompanying physiological changes The target audience includes physiologists, physicians and occupational health and safety practitioners Using the principles of thermodynamics, the avenues for human heat exchange are explored, leading to an evaluation of some methods used to assess thermally-stressful environments In particular, there is a critique of the wet-bulb globe temperature (WBGT) index, and an overview of an alternative means by which such assessments may be undertaken (the heat stress index) These principles and methods are combined to illustrate how one may evaluate the risk of heat illness Three general areas of research are briefly reviewed: the physiological impact of wearing thermal protective clothing, heat adaptation (acclimation) and whole-body pre-cooling These topics are considered as potential pre-exposure techniques that may be used to reduce the threat of hyperthermia, or to enhance work performance in the heat

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

Abstract: 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°C and 27.5°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.

Occupational heat stress assessment by the Predicted Heat Strain model.

Abstract: The work of the main European research teams in the field of thermal factors was coordinated in order to improve significantly the Required Sweat Rate model published as an international standard. Many significant modifications were brought, in particular concerning the effects of forced convection, body movements and exercise and the prediction of the skin temperature as a function of the rectal temperature and in case of severe conditions of radiation, humidity and clothing. The criteria for acceptable work durations in hot environments were updated concerning the maximum increase in core temperature and the acceptable water loss. The revised model, called Predicted Heat Strain model, was validated through a set of lab and field experiments involving stable and fluctuating conditions with high and low radiation, humidity and air velocity. It is meanwhile adopted as an ISO and CEN standard. In addition, a strategy was developed to assess the risks of heat disorders in any working situation. It is based on the three highest stages of the SOBANE strategy: an "Observation" method for improving simply the thermal conditions of work; an "Analysis" method to evaluate the magnitude of the problem and optimise the choice of solutions and an "Expert" method for in depth analysis of the working situation when needed.

Hot environment and health problems of outdoor workers at a construction site

Abstract: The aim of this research was to understand hot working environment at a construction site in summer and its effects on health of workers. In the subjective construction site, some measures, such as taking a break during work, setting tents and electric fans, and drinking cool water, had already been taken to reduce heat stress. Twelve male workers were examined. The WBGT outdoors during work varied from 23 to 34°C. The time-motion study revealed that one subject worked exceeding 7 hours, and that the other one had little rest time and drank little water during work. Few items of subjective symptoms increased after work compared with before work. In blood chemical data, electrolytes and blood urea nitrogen did not change. Blood sugar before work was significantly higher than before lunch and after work. Two subjects showed serum osmotic pressures increased after work. Two had the tendency to increase the blood pressure during work. The measures seemed effective, because the effects of work were not remarkable in general. However, some problems were still pointed out. Thus, stricter work control and health care for workers are necessary, such as controlling working hours strictly and monitoring the water intake during work.

The management of heat stress for the firefighter: a review of work conducted on behalf of the Toronto Fire Service.

Abstract: This report provides a summary of research conducted through a grant provided by the Workplace Safety Insurance Board of Ontario. The research was divided into two phases; first, to define safe work limits for firefighters wearing their protective clothing and working in warm environments; and, the second, to examine strategies to reduce the thermal burden and extend the operational effectiveness of the firefighter. For the first phase, subjects wore their protective ensemble and carried their self-contained breathing apparatus (SCBA) and performed very light, light, moderate or heavy work at 25 degrees C, 30 degrees C or 35 degrees C. Thermal and evaporative resistance coefficients were obtained from thermal manikin testing that allowed the human physiological responses to be compared with modeled data. Predicted continuous work times were then generated using a heat strain model that established limits for increases in body temperature to 38.0 degrees C, 38.5 degrees C and 39.0 degrees C. Three experiments were conducted for the second phase of the project. The first study revealed that replacing the duty uniform pants that are worn under the bunker pants with shorts reduced the thermal strain for activities that lasted longer than 60 min. The second study examined the importance of fluid replacement. The data revealed that fluid replacement equivalent to at least 65% of the sweat lost increased exposure time by 15% compared with no fluid replacement. The last experiment compared active and passive cooling. Both the use of a mister or forearm and hand submersion in cool water significantly increased exposure time compared with passive cooling that involved only removing most of the protective clothing. Forearm and hand submersion proved to be most effective and produced dramatic increases in exposure time that approximated 65% compared with the passive cooling procedure. When the condition of no fluid replacement and passive cooling was compared with fluid replacement and forearm and hand submersion, exposure times were effectively doubled with the latter condition. The heat stress wheel that was generated can be used by Commanders to determine safe work limits for their firefighters during activities that involve wearing their protective clothing and carrying their SCBA.

Evaluation of the environmental stress index (ESI) for hot/dry and hot/wet climates.

Abstract: Recently, a novel environmental stress index (ESI) which is composed from commonly used meteorological variables: ambient temperature (Ta), relative humidity (RH), and solar radiation (SR) was suggested as follows: ESI=0.63Ta-0.03RH+0.002SR+0.0054(Ta·RH)-0.073(0.1+SR)-1; (°C) The purpose of the present study was to evaluate and validate the ESI for hot dry and hot wet climatic conditions. The ESI was applied to large meteorological databases from 2 different locations resembling hot/wet and hot/dry climates. Data analysis revealed high correlation between ESI and the wet bulb globe temperature (WBGT) index for each of the two databases: P<0.05, R2=0.985 and 0.982, for the hot/dry and hot/wet conditions, respectively. Therefore, it is concluded that ESI, which is constructed from fast response and commonly used weather variables (Ta, RH, SR), and also found in a microsensor format is validated for hot/dry and hot/wet zones and as a potential index to serve as an alternative to the WBGT for heat category assessment.

Evaluation of occupational environment in two textile plants in Northern India with specific reference to noise.

Abstract: Occupational Noise exposure has been linked with a range of negative health effects by various researchers. The resulting injury of occupational hearing loss is also a well recognized and global problem. To protect workers from hearing damage due to noise exposure and other related health effects, a vast store of knowledge has been accumulated till date about its nature, etiology and time course. There is still ignorance, amongst majority of people working in industries in developing and third world countries including India about ill effects of exposure to high values of noise. The study being reported here has been carried out in two textile plants located in Northern Indian state of Punjab. Equivalent sound pressure level Leq has been measured in various sections of these plants with the help of a Class-I type digital sound level meter. The noise spectrum has been evaluated with the help of 1/3 octave filter set. A cross sectional study involving 112 workers exposed to different levels of occupational noise has been conducted. The results of the study establish the fact that noise level in certain sections of the plants i.e Loom Shed, Spinning, Ring Frame, TFO Area is more than the acceptable limit of 90 dBA for 8 h exposure stipulated by OSHA. The noise level in other sections like carding, blow room, combing etc., although is less than 90 dB(A) , but is quite higher than limits used for assessment of noise for community response. Octave band analysis of the noise shows the presence of high sound level in 4,000 Hz frequency range, which can be a major reason for causing occupational hearing loss. The results of the interview questionnaire which included a number of parameters reveal the following; (i) only 29% workers are aware about the effects of noise on health (ii) 28% workers are using ear protectors (iii) the satisfaction with the working environment is related to noise level, as workers exposed to comparatively less noise level report better satisfaction (iv) 70% of the workers reported that high noise level causes speech interference (v) 42% workers report the noise to be annoying. The study thus demonstrates the presence of gross occupational noise exposure in both the plants and the author believes that occupational noise exposure and the related effects in India is a widespread problem.

Physiological strain of miners at hot working places in German coal mines.

Abstract: As the percentage of shifts in hot working conditions in German Coal mines had increased to more than 50% during the last decade, a study was carried out to record the physiological strain of miners. Thirty-eight miners participated during 125 shifts. Heart rate and rectal temperature were measured continuously. Sweat losses as well as food and fluid uptake were estimated from measurements before and after shifts. During all shifts mean heart rates resulted in 102.8 min-1, mean rectal temperature was 37.7°C. Mean sweat loss per shift was 3,436 g; mean sweat rates resulted in 494 g/h. Rehydration during the shift at high climatic stress decreased to about 60% of sweat losses. In order to state the organizational frame of work at hot working places in German coal mines, the main features of regulations of work at hot working places are presented.

Exposure to organic solvents among handicraft car painters: A pilot study in Italy.

Abstract: Car repair painters usually experience long-term exposure to many different solvents. In Italy, the greater part of car painting shops are "handicraft", i.e. 2-5 workers and small premises. Usually workers do not have specific duties, but everyone takes part in all different operations. Moreover, working time is not standardized but varies according to the workload, working methods tend to be traditional, and compliance to individual protection devices is poor. We have hence assessed, on a sample of 8 italian handicraft car painting shops, the exposure levels to solvents, implementing three classic exposure monitoring methods: environmental sampling with charcoal tubes, personal sampling with diffusive charcoal samplers, and urinary determination of unmetabolised solvents. A simple regression analysis was performed to evaluate relationships between the three series of data. The solvents analysed were toluene, ethylbenzene, 1, 2-dichloropropane, n-butylacetate, n-amylacetate, xylene isomers, ethylacetate, and benzene. Benzene was included due to several factors, among others its presence (1% v/v) in the italian unleaded gasoline. Benzene was found in all shops, at levels around or higher than the 8-h time-weighted average limit (8-h TLV-TWA). Other solvents were found in the different shops at various levels, 10(-2) - 10(-1) times the 8-h TLV-TWA. Air concentrations of toluene, n-butylacetate, xylenes, and benzene were positively correlated with urinary levels of the parent compounds, while a negative correlation was found for ethylbenzene. The health implications of workers' exposure level was briefly discussed.

Central mechanisms for thermoregulation in a hot environment.

Abstract: Homeothermic animals regulate body temperature by autonomic and behavioral thermoeffector responses. The regulation is conducted mainly in the brain. Especially, the preoptic area (PO) in the hypothalamus plays a key role. The PO has abundant warm-sensitive neurons, sending excitatory signals to the brain regions involved in heat loss mechanisms, and inhibitory signals to those involved in heat production mechanisms. The sympathetic fibers determine tail blood flow in rats, which is an effective heat loss process. Some areas in the midbrain and medulla are involved in the control of tail blood flow. Recent study also showed that the hypothalamus is involved in heat escape behavior in rats. However, our knowledge about behavioral regulation is limited. The central mechanism for thermal comfort and discomfort, which induce various behavioral responses, should be clarified. In the heat, dehydration affects both autonomic and behavioral thermoregulation by non-thermoregulatory factors such as high Na+ concentration. The PO seems to be closely involved in these responses. The knowledge about the central mechanisms involved in thermoregulation is important to improve industrial health, e.g. preventing accidents associated with the heat or organizing more comfortable working environment.

Dissolution of Functional Materials and Rare Earth Oxides into Pseudo Alveolar Fluid

Abstract: The dissolution rates of rare earth oxides and two types of rare earth containing functional materials into water, saline solution, and Gamble's fluid were measured in order to evaluate the biological effects of rare earth-containing functional materials. The tested materials were yttrium, lanthanum, cerium and neodymium oxides, and neodymium-boron-iron magnet alloy (NdBFe) and lanthanum-mish-metal-nickel-cobalt (LmNiCo) hydrogen-containing alloy. The dissolution rates of the rare earth oxides were very low, resulting in concentrations of rare earth elements in the test solutions of the order of ppb. In the most extreme case, Gamble's fluid dissolved 1,400 times more of the rare earth oxides than pure water. Fairly high concentration of neodymium were found in the dissolving fluids, which means that trace neodymium present as an impurity in each rare earth oxide dissolved preferentially. For yttrium oxide, the ratio of neodymium to yttrium that dissolved in the saline solution was greater than 78,000 to 1, taking into account the amount of each that was originally present in the yttrium oxide.

Advances in participatory occupational health aimed at good practices in small enterprises and the informal sector.

Abstract: Participatory programmes for occupational risk reduction are gaining importance particularly in small workplaces in both industrially developing and developed countries. To discuss the types of effective support, participatory steps commonly seen in our "work improvement-Asia" network are reviewed. The review covered training programmes for small enterprises, farmers, home workers and trade union members. Participatory steps commonly focusing on low-cost good practices locally achieved have led to concrete improvements in multiple technical areas including materials handling, workstation ergonomics, physical environment and work organization. These steps take advantage of positive features of small workplaces in two distinct ways. First, local key persons are ready to accept local good practices conveyed through personal, informal approaches. Second, workers and farmers are capable of understanding technical problems affecting routine work and taking flexible actions leading to solving them. This process is facilitated by the use of locally adjusted training tools such as local good examples, action checklists and group work methods. It is suggested that participatory occupational health programmes can work in small workplaces when they utilize low-cost good practices in a flexible manner. Networking of these positive experiences is essential.

Effects of Perinatal Exposure to Bisphenol A on Brain Neurotransmitters in Female Rat Offspring

Abstract: Pregnant Sprague-Dawley (CD IGS) rats were orally administered doses of bisphenol A (BPA) at 4, 40, and 400 mg/kg, from gestation days 6 to postnatal day 20. Neurotransmitters such as dopamine (DA) and serotonin (5HT) were extracted from the brains of dams and female offspring, and measured using liquid chromatography. BPA at 400 mg/kg was toxic and dosed rats died. At 3 wk after birth, brain levels of 3,4-dihydroxyphenylacetic acid (DOPAC, a DA metabolite), homovanillic acid (HVA, a DA metabolite), 5HT, 5-hydroxyindoleacetic acid (5HIAA, a 5HT metabolite) in female offspring were increased and the HVA/DA ratio was high in some brain areas of BPA-treated groups as compared with controls. At the age of 6 wk, levels of choline (Ch) in BPA-treated groups at 4 and 40 mg/kg were higher than control in all of eight brain areas. No changes were observed in acetylcholine (ACh) contents. In 9-wk-old offspring, changes in monoamines and metabolites were scattered and not great. At 3 wk after delivery, levels of 5HIAA in some brain areas of dams treated with BPA were higher than in control dams. Dose dependent increases in HVA and the HVA/DA ratio of the occipital cortex, and in the HVA/DA ratio of the frontal cortex were observed. The turnover of DA and 5HT was accelerated in 3-wk-old offspring and dams. BPA possesses very weak estrogenic activity. Changes in cerebral neurotransmitters observed in offspring and dams in this study may have been related to the estrogenic activity of BPA. However, further investigation is needed to examine the contribution of hormonal activity to such neurotransmitter changes.

Prevalence of respiratory symptoms among workers in industries of south Tehran, Iran.

Abstract: Objective: The aim of the present study was to determine the prevalence of respiratory symptoms from occupational lung hazards among workers in industries of south Tehran, IRAN. Methodology: This was a cross-sectional study in which by multistage random sampling items on demographic characteristics, cigarette smoking, occupational history and respiratory symptoms were collected of workers. Results: The mean age of the workers was 38.5 (SD = 10.2) yr: age ranged from 19 to 70 yr. Of 880 workers under study, 252 (28.7%) were smoking. Also, it has been observed that workers exposed in the workplace with occupational chemical exposures such as dust, gas and fume pollutants. The prevalence of respiratory symptoms was cough (20.7%), phlegm (41.6%), dyspnea (41.7%), feel tightness (27.4%) and nose irritation (23.5%). Conclusions: Occupational exposures among workers in industries of south Tehran may cause respiratory symptoms and respiratory disorders, engineering controls and industrial hygiene is recommended.

Prevalence of and Risk Factors for Low Back Pain among Staffs in Schools for Physically and Mentally Handicapped Children

Abstract: The objective of this study is to clarify the prevalence of and risk factors for low back pain (LBP) in schools for physically and mentally handicapped children. This study design is a cross-sectional study. The subjects included were 1,869 staff members from 19 prefectural schools for children in Shizuoka Prefecture, Japan, which included schools for the blind, deaf-mutes, physically handicapped, and mentally retarded children. A total of 975 subjects completed two postal questionnaires which included morbidity, demographic factors, nursing activity, and psychosocial factors. The answer rate was 52%. The one-month prevalence of LBP was 45%. According to the classification of nursing activity, assistance in movement 1.67 (95% CI 1.27-2.14), excretory function 1.45 (1.11-1.88), and feeding 1.44 (1.10-1.90) showed significant increases in the odds ratio. The adjusted odds ratio significantly increased by 2.35 (1.78-3.11) in the group with depression symptoms as well as in the group with job stressors such as quantitative, qualitative, and physical work loads, job control, utilization of technique, interpersonal conflicts, and degree of satisfaction with their work/home life.

Approaches to Occupational Health Based on Participatory Methodology in Small Workplaces

Abstract: An intervention based on the methodology developed by the International Labour Office, the Work Improvement in Small Enterprises (WISE) was carried out to improve work condition of small-scale enterprises and the informal sector in the Philippines, Thailand and Japan. Through the evaluation of the efficacy of the approaches based on participatory methodology, it is concluded that the method is an efficient measure to improve work condition in small workplaces. It is also pointed out that the activities of supporting experts such as introduction of the methodology and evaluation of the activity are necessary. The important roles of the experts are 1) to encourage managers and workers to sustain the activities for work improvement, 2) to analyse the effectiveness and problems of the implemented improvements, 3) to give appropriate suggestions for the further improvement, and 4) to get materials for demonstrating the effectiveness of WISE activities on improving work conditions and productivity to other managers and workers who have not participated in the activity.

Respirable dust exposure and respiratory health in male Taiwanese steelworkers.

Abstract: The objective of this cross-sectional study was to investigate the prevalence and determinants of respiratory symptoms and lung function and their association with occupational dust exposure in Taiwanese steelworkers. The study was conducted on an integrated-steel company in Taiwan from March 1989 to February 1990. After excluding workers in the coke ovens and ex-smokers, we performed physical examinations on 1,339 male workers in the iron making and steel making factories. Subjects were interviewed regarding respiratory symptoms using a Chinese version of the American Thoracic Society respiratory questionnaire and were examined with respect to their lung function using spirometry. Objective dust exposure was measured using personal air sampling with 277 valid samples. Prevalences of cough frequently, chronic cough, phlegm frequently, chronic phlegm, wheezing occasionally, and breathlessness were 11.4%, 9.3%, 14.6%, 11.9%, 2.6%, and 6.5%, respectively. Duration of employment, smoking, subjective dustiness, and past respiratory illnesses can predict these respiratory symptoms. Average respirable dust exposure significantly decreased the forced vital capacity (FVC) and forced expiratory volume in one second (FEVI.0) in smoking workers. In the non-smokers, an effect of respirable dust exposure on FEVl.0/FVC was shown. Since the main ingredients of dust in such a steelworks usually contained mixtures of oxides and silicates other than silica dust, respirable dust exposure in steelworks might impair lung function, especially among smokers.

Relationship of blood lead levels to blood pressure in exhaust battery storage workers.

Abstract: Several researches has focused the hypothesis that low blood lead levels could be asso- ciated with an increased risk of hypertension. To assess the relation between occupational lead exposure and elevated blood pressure a group of 27 workers, age range from 27 to 62 years, mean (SD) 36.52 (± 8.16) yr; length of employment mean (DS) 2.97 (± 1.67) yr, were recruited as study subjects. The following variables were measured: blood lead concentration (BPb), δ- Aminolevulinic Acid Dehydratase (ALAD) activity, Zinc Protoporphirin (ZPP), creatinine, hema- tocrit, Body Mass Index (BMI) and Systolic Blood Pressure (SBP) and Diastolic Blood (DBP) Pressure. The results showed that long term occupational exposure was related to a slight increase of systolic and diastolic blood pressure among workers who had been exposed to high- er level of lead with respect to workers exposed to lower level of lead. Furthermore, blood lead concentration (BPb) and ZPP resulted higher among workers exposed to higher level of ambi- ent lead, while in the same group of workers ALAD activity resulted more inhibited. The authors concluded long term cumulative lead exposure can significantly increase blood pressure in low level Pb exposed workers.

Strengthening the self-care of women working in the informal sector: local fabric weaving in Khon Kaen, Thailand (Phase I).

Abstract: The first phase of this study was undertaken using Participatory Action Research (PAR) to identify the factual situations of fabric-weaving women working in the informal sector in Thailand The aims were to enhance the mutual understanding of the women and researchers concerning the problems faced by these women and to establish an action plan to address these problems The participant group consisted of 107 women working in the informal sector from three local villages who voluntarily took part in the study Data were collected using quantitative and qualitative methods through structured questionnaires, focus groups, in-depth interviews, participant observations, and field notes The results of the study revealed that the women learned their health problems were related to work and their labor potentially placed them at a risk for illness When the women realized the gravity of their situation, they attained a sense of empowerment and took the initiative in establishing action plans to address their problems

A Field Evaluation Method for Assessing Whole Body Biomechanical Joint Stress in Manual Lifting Tasks

Abstract: Work-related musculoskeletal injuries are often associated with overexertion of the body at work. The manual materials handling activity of lifting is a major source of work-related musculoskeletal disorders. Biomechanical evaluation offers useful information about the physical stress imposed on the worker's body joints; however, biomechanical analysis is usually tedious and complex. For evaluation purpose, the biomechanical method needs to be easy to apply in a field environment. Manual lifting occurs as one of the most common manual materials handling tasks in the workplace. A biomechanical evaluation method was developed based on the ratio of joint moment to joint capacity. The method was applied to evaluate the physical stress of manual lifting in truck loading jobs using a nine-link whole body joint model. Thirty eight industrial tasks were evaluated using the developed joint moment ratio. The moment ratio was compared with subjectively rated body discomfort, overall workload, and the NIOSH lifting index. The moment ratio was found to have a high correlation with the NIOSH lifting index. The biomechanical method can be used with relatively simple equipment and procedure which may be suitable for on-site ergonomic evaluation.

Research Priorities in Occupational Safety and Health: A Review

Abstract: Changes in the world of work in the last few decades have markedly affected questions regarding occupational safety and health (OSH). Jobs in our economy continue to shift from manufacturing to services. Longer hours, shift work, reduced job security, temporary work are realities in the modern workplace, new chemicals, materials, processes are developed at an ever accelerating pace. The workforce is also changing. It will become older and more racially diverse and women are increasing. These changes present new challenges to protect worker safety and health and it was been indispensable to redefine priorities, by consulting all those involved in OSH. The present study therefore made a critical comparative analysis of the main published projects to identify research priorities in the OSH field, comparing methods, approaches and results. Comparison of the priority areas established in each of these studies is inherently difficult due to differences in socio-cultural backgrounds, in the methods employed to identify priority topics, and the many factors involved. However, it is clear that the Delphi technique is widely used as a reliable method, in that it covers a broad range of qualified witnesses, from a variety of backgrounds--such as trade union representatives and researchers--providing different viewpoints. It also takes account of the intrinsic features of OSH which--compared to other disciplines--involves multidisciplinary factors calling into play a range of scientific settings, such as toxicologists, molecular biologists, epidemiologists, occupational hygienists and occupational physicians. This analysis showed how important it is to reach consensus among all those operating in the OSH sector, in order to establish standard methods that can be applied in different contexts, and give results that can be validly compared.

Heat Strain in Cold

Abstract: In spite of increased environmental cold stress, heat strain is possible also in a cold environment. The body heat balance depends on three factors: environmental thermal conditions, metabolic heat production and thermal insulation of clothing and other protective garments. As physical exercise may increase metabolic heat production from rest values by ten times or even more, the required thermal insulation of clothing may vary accordingly. However, in most outdoor work, and often in indoor cold work, too, the thermal insulation of clothing is impractical, difficult or impossible to adjust according to the changes in physical activity. This is especially true with whole body covering garments like chemical protective clothing. As a result of this imbalance, heat strain may develop. In cold all the signs of heat strain (core temperature above 38°C, warm or hot thermal sensations, increased cutaneous circulation and sweating) may not be present at the same time. Heat strain in cold may be whole body heat strain or related only to torso or core temperature. Together with heat strain in torso or body core, there can be at the same time even cold strain in peripheral parts and/or superficial layers of the body. In cold environment both the preservation of insulation and facilitation of heat loss are important. Development of clothing design is still needed to allow easy adjustments of thermal insulation.

Associations of Health Behaviors on Depressive Symptoms among Employed Men in Japan

Abstract: The associations between health behaviors and depressive symptoms have been demonstrated in many studies. However, job strain has also been associated with health behaviors. The aim of this study was to analyze whether health behaviors such as physical activity, sleeping, smoking and alcohol intake are associated with depressive symptoms after adjusting for job strain. Workers were recruited from nine companies and factories located in east and central areas of Japan. The Center for Epidemiologic Studies Depression (CES-D) Scale was used to assess depressive symptoms. Psychological demand and control (decision-latitude) at work were measured with the Job Content Questionnaire. Multiple logistic regression analysis was used to determine the independent contribution of each health behavior to depressive symptoms. Among the total participants, 3,748 (22.7%) had depressive symptoms, which was defined as scoring 16 or higher on the CES-D scale. Using the multiple logistic regression analysis, depressive symptoms were significantly associated with physical activity less than once a week (adjusted relative risk [ARR] = 1.18, 95% confidence interval [CI], 1.14 to 1.25) and daily hours of sleep of 6 h or less (ARR, 1.25; 95% CI, 1.14 to 1.35). Smoking and frequency of alcohol intake were not significantly associated with depressive symptoms. This study suggests some health behaviors such as physical activity or daily hours of sleep are associated with depressive symptoms after adjusting for job strain.

Occupational low back pain among workers in some small-sized factories in Ardabil, Iran.

Abstract: The main purpose of this study was to assess some of the individual and occupational risk factors contributing to induction or intensification of LBP among the employees suffering from this problem in four small size factories in Ardabil, Iran. This study was a cross-sectional study that was conducted among the personnel of four industrial companies. Interview, questionnaire survey, medical examination (Lasegue test), radiographic evaluation, and ergonomic survey (using the NIOSH checklist) were the methods to collect data. The result of the study was divided into two parts: individual factors and work-related factors. The highest frequency of low back pain was observed in the age of 30-34 years old, medium height and heavy weight with 34.4, 84.4, and 33.0 percent, respectively. With regard to work-related factors, load lifting with 44.7 and body posture with 18.4 percent contributed to low back pain as the most important occupational causes among the patients. Observing recommended regulations and limitations of load lifting, modifying and optimizing ergonomic conditions in the workplace, selecting workers with suitable body strength on the basis of a pre-employment examination and implementing a continuous educational program for employees were the most important methods recommended to prevent low back pain.