Lead oxide is used extensively in the construction and repair of wooden boats in Thailand, but the behaviors of boatyard workers that could place them at risk of contamination have not previously been documented. Baseline data on practices and behaviors of boatyard workers and on the level of worker and workplace contamination with lead were therefore collected. Fifty workers in two boatyards participated in this study. Lead exposure of workers was assessed by determining airborne and blood lead levels. A questionnaire was administered to collect information on work history, suspected exogenous lead sources, personal behavior and knowledge about lead. Evidence obtained by the study indicated that safety behavior and personal hygiene were poor-workers used no mask, gloves or hood, wore open sandals, smoked, drank, chewed and ate during work and did not wash their hands before drinking or eating. Some workers had lunch in the working area. The mean personal airborne lead of caulkers (36.4 μg/m³) was higher than that of carpenters (8.3 μg/m³). Forty-eight percent of all workers and 67% of caulkers had a blood lead level (BLL) exceeding 40 μg/dl. Multiple linear regression indicated that blood lead levels of workers were significantly related to job and education level, with significant differences between boatyards. In addition, the potential for "take-home" contamination was high; none of the workers took a shower or changed their clothes prior to going home. These results indicate a problem of lead exposure of sufficient magnitude to be a public health concern.

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Peroxisome proliferator-activated receptor α (PPARA α) plays a pivotal role in lipid metabolism. Our previous study reported that PPARA-V227A was a major polymorphism in Japanese, which was associated with markedly lower serum total cholesterol (TC) levels, which were significantly affected by alcohol drinking compared to subjects with the wild-type (PPARA-WT) allele. However, serum lipids are also associated with aging and exercise frequency. The objective of the present study was to evaluate the relationship between PPARA-V227A and these factors. Genetic analysis of the polymorphism was performed in 1058 Japanese men and 281 women, and the relationship with aging, drinking and exercise on serum lipids was analyzed in 989 men and 245 women after exclusion criteria had been applied. In men, drinking increased high-density lipoprotein cholesterol (HDL-C) levels in both PPARA-WT and A227 carriers, but to a significantly higher degree in the latter. In women, TC and low-density lipoprotein cholesterol (LDL-C) levels in the A227 carriers drinking at least once a week were significantly higher than in PPARA-WT carriers. TC and LDL-C levels in males with PPARA-WT increased with aging regardless of drinking habit, while LDL-C levels in the A227 drinking carriers were significantly lower in 45-yr-old or older subjects than in 35- to 45-yr-olds. In addition, no effect of exercising was observed in the A227 carriers, while increase in the HDL-C of the PPARA-WT carriers was exercise frequency dependent. These results suggest that the influence of drinking, aging or exercise on TC, LDL-C and HDL-C levels in the A227 carriers may be different from those in the PPARA-WT subjects.

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Excessive alcohol consumption is associated with increased risks of many diseases including cancer. We evaluated oxidative DNA damage in Aldh2 +/+ and Aldh2 -/- mice after they had been subjected to acute ethanol exposure. Olive tail moment, which was measured using a comet assay, was not increased by ethanol treatment in both Aldh2 +/+ and Aldh2 -/- mice. However, after controlling for the effect of ethanol exposure, the Aldh2 genotype was a significant determinant for Olive tail moments. Although the ethanol treatment significantly increased the hepatic 8-OHdG generation in only Aldh2 +/+ mice, the level of 8-OHdG was the highest in Aldh2 -/- ethanol treated mice. The increase in the level of 8-OHdG was associated with hepatic expression of cytochrome P450 2E1 (CYP2E1). The levels of Olive tail moment and the hepatic 8-OHdG in the Aldh2 -/- control group were significantly higher than those of the Aldh2 +/+ control group. The level of CYP2E1 in liver tissue showed a similar pattern to those of the oxidative DNA damage markers. This study shows that acute ethanol consumption increases oxidative DNA damage and that expression of CYP2E1 protein may play a pivotal role in the induction of oxidative DNA damage. The finding that oxidative DNA damage was more intense in Aldh2 -/- mice than in Aldh2 +/+ mice suggests that ALDH2-deficient individuals may be more susceptible than wild-type ALDH2 individuals to ethanol-mediated liver disease, including cancer.

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To assess the associations between job stress and somatic symptoms and to investigate the effect of individual coping on these associations. In July 2006, a cross-sectional study was conducted during a periodic health check-up of 185 Japanese male office workers (21-66 yr old) at a Japanese company. Job stress was measured by job demand, control, and strain (=job demand/control) based on the Job Content Questionnaire (JCQ). Major somatic symptoms studied were headache, dizziness, shoulder stiffness, back pain, shortness of breath, abdominal pain, general fatigue, sleep disturbance, and skin itching. Five kinds of coping were measured using the Job Stress Scale: active coping, escape, support seeking, reconciliation, and emotional suppression. Comorbidities of hypertension, diabetes, obesity, depression, and anxiety were also evaluated. The most frequently cited somatic symptom was general fatigue (66%), followed by shoulder stiffness (63%) and sleep disturbance (53%). Of the five kinds of coping, only "active coping" was significantly and negatively associated with the number of somatic symptoms. The generalized linear models showed that the number of somatic symptoms increased as job strain index (p=0.001) and job demand (p=0.001) became higher, and decreased as active coping (p=0.018) increased, after adjusting for age and comorbidities. There was no statistical interaction among active coping, the number of somatic symptoms, and the three JCQ scales. Reporting somatic symptoms may be a simple indicator of job stress, and active coping could be used to alleviate somatization induced by job stress.

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The objective of this study was to assess the degree of agreement between body mass index (BMI) and weight perception of Japanese office workers between the ages of 20 and 65. We sent 43,064 self-administered health-related questionnaires to all employees of a financial firm in Japan in October 2004. The questionnaire asked the respondents for their height, weight, and their weight perception. The kappa coefficient was calculated to investigate the degree of agreement between the BMI calculated using the self-reported data and weight perception for three categories. Of the questionnaires, 34,921 (81.1%) were returned and 33,514 responses (77.8%) were used for the analysis. Based on Japanese obesity criteria, 2,202 men (31.2%) and 5,145 women (19.5%) were obese; and 179 men (2.5%) and 2,769 women (10.5%) were underweight. The kappa coefficient was 0.374 for men and 0.297 for women. The kappa coefficients for different age groups-twenties, thirties, forties, fifties, and sixties (up to 65)-were respectively as follows: 0.315, 0.355, 0.374, 0.406, and 0.425 for men; and 0.194, 0.275, 0.285, 0.334, and 0.355 for women. In conclusion, the degree of agreement between BMI and weight perception differed by age and sex. The degree of agreement was smaller among women than among men and the degree of agreement among younger women was weaker than among older women.

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This study prospectively examined the association between perceived noise exposure at work and cerebrovascular diseases among Japanese male workers. A baseline survey was conducted between 1988 and 1990, which involved 110,792 inhabitants (age range: 40-79 yr) from 45 areas throughout Japan. Subsequent causes of death were identified from death certificates. The analysis was restricted to 14,568 men free of a cerebrovascular diseases (age range: 40-59 yr) who were in work at the time of the baseline survey. All subjects completed a self-administered questionnaire at the baseline. This included a question regarding perceived noise exposure at work. The Cox proportional-hazards model was used to estimate the risks of perceived noise exposure for death due to cerebrovascular diseases. The model included age, smoking, alcohol consumption, educational level, perceived mental stress, past medical history, body mass index, hours of walking, hours of exercise, shift work, and job type. During the 190,777 person-years of follow-up, a total of 1,064 deaths were recorded, 98 from cerebrovascular diseases, 27 deaths from subarachnoid haemorrhage, 35 deaths from intracerebral haemorrhage, and 25 deaths from cerebral infarction. Noise exposure did not increase the risk of cerebrovascular diseases, subarachnoid haemorrhage, or cerebral infarction. However, perceived noise exposure increased the risk of intracerebral haemorrhage diseases (hazard ratio (HR)=2.38, 95%CI: 1.20, 4.71, p=0.013). Furthermore, individuals with hypertension were highly susceptible to the effect of perceived noise exposure on the risk of intracerebral hemorrhage, but this association was not observed among the subjects without hypertension. Although the underlying mechanisms are not clear, hypertensive individuals with perceived noise exposure at work should be regarded as a high-risk group for intracerebral hemorrhage.

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Oxidative DNA damage may play an important role in the human carcinogenic process. Recently, we reported a case of bladder cancer among 4, 4'-methylenebis (2-chloroaniline) (MBOCA)-exposed workers. By measuring the plasma level of 8-hydroxydeoxyguanosine (8-OHdG), we investigated the association between oxidative DNA damage and MBOCA exposure. In addition, we examined the effects of different confounders on the plasma level of 8-OHdG. We undertook a cross-sectional survey at four MBOCA-producing factories in Taiwan (158 subjects). Plasma 8-OHdG levels and urinary MBOCA concentrations were measured by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). Personal characteristics were collected by questionnaire. The workers were classified according to their job titles as exposed (n=57) or unexposed (n=101) groups as well as classified according to urinary MBOCA levels as high urinary MBOCA (>20 μg/g creatinine) (n=45) or low urinary MBOCA (n=108) groups. Neither the MBOCA-exposed workers nor the high urinary MBOCA workers had a significant increase in the mean plasma 8-OHdG level, even after adjustment for potential confounders. Age and gender were significantly positively correlated with plasma 8-OHdG levels. Smokers among high urinary MBOCA workers also had significantly higher 8-OHdG levels than non-smokers among high urinary MBOCA workers. Our study provides evidence that smoking rather than MBOCA exposure induces elevation of plasma 8-OHdG levels among workers exposed to MBOCA, indicating that oxidative DNA damage does not play an important role in the carcinogenic processes of MBOCA.

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This study set out to assess the respirable mass, surface area, and number concentrations of the α-quartz content particles (C_r-m, C_r-s and C_r-n) to which workers were exposed in six different exposure groups, the raw material handling (n=10), crushing (n=12), mixing (n=12), forming (n=10), furnace (n=10), and packaging (n=10), in a refractory material manufacturing plant. For C_r-m, the exposure values in sequence were found as: mixing (68.1 μg/m³)>packaging (55.9 μg/m³)>raw material handling (53.3 μg/m³)>furnace (31.0 μg/m³)>crushing (29.8 μg/m³)>forming (22.4 μg/m³). We also found that ~21.2-68.2% of the above Cr-m exceeded the current TLV-TWA for the α-quartz content (50 μg/m³) suggesting a need for initiating control strategies immediately. We further conducted particle size-segregating samplings in four workplaces: crushing (n=3), mixing (n=3), forming (n=3), and furnace (n=3). We found that all resultant particle size distributions shared a quite similar geometric standard deviation (σ_g; =2.24-2.92), but the process area, associated with higher mechanical energy (i.e., crushing process), contained finer α-quartz content particles (mass median aerodynamic diameter; MMAD=3.22 μm) than those areas associated with lower mechanical energy (i.e., mixing, forming, and furnace; MMAD=6.17, 5.95, and 8.92 μm, respectively). These results gave a ratio of C_r-m in the above four exposure groups (i.e., crushing: mixing: forming: furnace=1.00: 2.30: 0.753: 1.04) which was quite different from those of C_r-s (1.00: 1.74: 0.654: 0.530) and C_r-n (1.00: 1.27: 0.572: 0.202). Our results clearly indicate the importance of measuring particle size distributions for assessing workers' free silica exposures.

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Musculoskeletal disorders (MSDs) are a common health problem throughout the world and a major cause of disability among the work force. Assessment of exposure level to MSD risk factors can be an appropriate base for planning and implementing interventional ergonomic programs in the workplace. This study was conducted among workers of an Iranian rubber factory with the objectives of (a) determination of the prevalence of MSDs among production line workers, and (b) assessment of the level of exposure to MSD risks. In this study, all 16 production units of the factory were studied. In each unit, 50% of the workers were randomly selected and included in the study. A total of 454 workers participated. The Nordic Musculoskeletal Questionnaire was used to study the prevalence of MSDs and the Quick Exposure Check (QEC) technique was applied to assess physical exposure to the risks. The videotaping technique was used to collect the required data for each worker. The vast majority of the workers (73.6%) had suffered from some kind of musculoskeletal symptoms during the last 12 months. The highest prevalence was reported in the lower back (50.2%), knees (48.5%) and upper back (38.1%). In 85.5% of the workers studied, the QEC score was high or very high. Statistical analysis showed a significant association between the QEC level of risk and MSDs symptoms (p<0.001). The most common ergonomics problems were found to be awkward postures and manual material handling. MSDs had occurred with a high rate among workers of this rubber factory. Corrective measures for reducing risk level seemed essential. Elimination of awkward postures and manual material handling in the workplace were recommended.

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Needlestick/sharp injuries (NSIs/SIs) are a serious threat to medical/nursing students in hospital internships. Education for preventing NSIs/SIs is important for healthcare workers but is rarely conducted and evaluated among vocational school nursing students. We conducted an educational intervention for such students after their internship rotations before graduation. This program consisted of a lecture to the students after the internship training and a self-study brochure for them to study before their graduation. This study used the pre-test questionnaires completed by all students and the post-test questionnaires completed by 107 graduates after work experience as licensed nurses to assess the effectiveness of the intervention. After educational intervention, the incidence of NSIs/SIs decreased significantly from 50.5% pre-test to 25.2% post-test, and the report rate increased from 37.0% to 55.6%, respectively. In conclusion, this intervention significantly reduced the incidence of NSIs/SIs and increased the report rate of such events.

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Minako Watanabe should have appeared Mamiko Watanabe. Wrong:Akiko Nogi^1,2, Jianjun Yang¹, Limei Li¹, Masayuki Yamasaki¹, Minako Watanabe¹, Michio Hashimoto³ and Kuninori Shiwaku^1
1Department of Environmental and Preventive Medicine, Shimane University School of Medicine,
²Department of Human Nutrition, Faculty of Human Life Science, Yamaguchi Prefectural University and
³Department of Environmental Physiology, Shimane University School of Medicine, Japan
Right:Akiko Nogi^1,2, Jianjun Yang¹, Limei Li¹, Masayuki Yamasaki¹, Mamiko Watanabe¹, Michio Hashimoto³ and Kuninori Shiwaku^1
1Department of Environmental and Preventive Medicine, Shimane University School of Medicine,
²Department of Human Nutrition, Faculty of Human Life Science, Yamaguchi Prefectural University and
³Department of Environmental Physiology, Shimane University School of Medicine, Japan

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