To assess dermal absorption of nicotine from tobacco leaves in relation to Green Tobacco Sickness (GTS), urinary cotinine concentrations were measured in 80 male tobacco-growing farmers and in 40 healthy males (controls) who did not handle wet tobacco leaves in Kelantan, Malaysia. Among non-smokers, urinary cotinine levels in farmers were significantly higher than those of controls; farmers with urinary cotinine of 50 ng/ml/m² or above showed eye symptoms more frequently than those below this level (p<0.05). Farmers who did not wear protective equipment had subjective symptoms more frequently than those who used the equipment (p<0.05); some of these symptoms were seen more frequently in organophosphate (Tamaron) users than in non-users. As tobacco farmers evidence a risk of nicotine poisoning from tobacco leaves, assessment including GTS together with effects of pesticides will be necessary.

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Objectives-Noise is one of the commonest physical stressors to which industrial workers are exposed. Many workers complain of symptoms associated with a non-specific generalized stress response, including disturbed sleep. However, industrial workers may be exposed to more than one source of stress and it is not possible to completely attribute the disturbed nocturnal sleep and changes in heart rate to the effects of loud noise alone. This study was done to find out whether acute exposure of healthy individuals to loud occupational noise during the daytime would cause changes in their nocturnal sleep architecture, heart rate during sleep and serum cortisol levels. Methods-Baseline polysomnography was done on ten subjects who were exposed for eight hours either to continuous occupational background noise levels of >75dB(A), or a quiet environment. Sleep polysomnography was done on the night prior to and after exposure. Blood was collected for serum cortisol estimation at night prior to sleep and in the morning after waking up. Statistical analysis was done by repeated measures ANOVA with Tukey's post test. Results-The sleep efficiency was less than 80% and the total time spent in Rapid Eye Movement (REM) sleep, Slow Wave Sleep (SWS) and the REM onset latency were significantly decreased on the night after exposure to noise. There was a significant increase in stage shifts. The percentage fall in heart rate during sleep was decreased compared to the baseline values. The serum cortisol levels in the morning after exposure to noise was significantly increased. Conclusion-Workers exposed to loud background occupational noise react to the stress and show changes in nocturnal sleep architecture and heart rate which may be contributed to the exposure to noise.

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This study was conducted on a thermal exposure chamber designed for assessing workers’ thermal hazard. In order to assess the efficacy of the studied chamber, three environmental conditions were selected to simulate high, middle and low thermal impact situations, with air temperatures (T_a) of 43.12, 36.23 and 25.77ºC, globe temperatures (T_g) of 44.41, 41.07 and 29.24ºC, relative humidity (RH) of 77, 59 and 39 %, and air flow velocities (V_a) of 1.70, 0.91 and 0.25 m/s, respectively. For the three specified thermal impact conditions, results show that the coefficients of variation (CVs) for T_a, T_g, RH and V_a measured in the chamber studied were consistently less than 10%, except for V_a under the low thermal impact condition (=50%). For each specified thermal impact condition, we generated 1,000 environmental combinations by using the Monte Carlo simulation approach according to the variations obtained from the four environmental factors. We directly adopted the ISO 7933 approach to estimate the allowable exposure time (AET) for each simulated environmental condition. This study yielded a range in the 95% confidence interval (95% CI) of the estimated AETs for the three specified thermal impact conditions which were consistently less than 5 min. We further conducted the sensitivity analysis to examine the effect of the four environmental factors on estimating AETs. We found V_a was the least important factor in estimating AETs for any specified thermal impact condition. In conclusion, although V_a was found with great variation for the chamber specified in the low thermal impact condition, the exposure chamber studied can still be regarded as a feasible one for assessing workers’ thermal hazard.

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This study was designed to investigate the relationship between environmental exposure to polycyclic aromatic hydrocarbons (PAHs) and oxidative stress, and to evaluate the effects of cigarette smoking and the genetic polymorphisms of CYP1A1, CYP2E1, GSTM1, NAT2 and UGT1A6 on the relationship. The subjects of this study were 105 healthy Korean males without occupational exposure to PAHs. The 8-hydroxydeoxyguanosine (8-OHdG) level in leukocytes, and urinary 1-hydroxypyrene (1-OHP) and 2-naphthol concentrations, were measured by high-performance liquid chromatography. Genetic polymorphisms of CYP1A1, CYP2E1, GSTM1, NAT2 and UGT1A6 were identified by PCR and PCR-RFLP methods. The 8-OHdG level showed a significant correlation with the 1-OHP concentration in all subjects (p< .001) and in smokers (p< .01), and with the 2-naphthol level in non-smokers (p< .01). The 8-OHdG level was significantly higher in smoking rapid acetylators than in smoking slow or intermediate acetylators, and in individuals with the UGT1A6 wild-type than in those with the UGT1A6 mutant genotype. Significant positive correlations between 8-OHdG and 1-OHP concentrations were found in subjects with every genotype of the CYP1A1 and CYP2E1 genes, with the GSTM1 null-type, with the NAT2 genotype of a rapid acetylator, and with the UGT1A6 wild-type, respectively. The urinary 2-naphthol level significantly correlated with the 8-OHdG level only in subjects with the GSTM1 null-type. In conclusion, there is a significant correlation between the 8-OHdG level in leukocytes and the urinary 1-OHP concentration in the population not occupationally exposed to PAHs. This relationship is affected by genetic polymorphisms in PAH metabolic enzymes.

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Hospital waste incinerator workers are exposed to various pyrolysis products including polycyclic aromatic hydrocarbons (PAHs). We evaluated their exposure by assessing urinary 1-hydroxypyrene glucuronide (1-OHPG), as an internal dose of PAH exposure. The potential effect of genetic polymorphisms of GSTM1/T1 involved in PAH metabolisms was also investigated. Pre- and post-shift samples were collected from 28 hospital incinerator workers. Urinary 1-OHPG was assayed by synchronous fluorescence spectroscopy (SFS) after immunoaffinity purification with the monoclonal antibody 8E11. Genotypes of GSTM1/T1 were assessed by PCR-based methods. Information on smoking habits and use of personal protective equipment were collected by means of a self-administered questionnaire. The Mann-Whitney test was used to compare group means of these biomarkers. Urinary 1-OHPG levels were similar in pre- and post-shift urine samples. The arithmetic mean concentrations of urinary 1-OHPG were 0.16 ± 0.04μmol/mol creatinine pre-shift and 0.19 ± 0.09μmol/mol creatinine post-shift, but urinary 1-OHPG levels were significantly higher in individuals with the GSTM1 null genotype than with the GSTM1 present genotype (p=0.05, by Mann-Whitney test). Our results suggest that the urinary 1-OHPG levels in hospital waste incinerator workers may be modified by the GSTM1 genotype, but these findings remain to be confirmed in future studies involving larger sample sizes.

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Medical students face the threat of needle stick injury with the consequent risk of acquiring blood-borne infection by pathogens such as HIV, Hepatitis B and Hepatitis C while performing their clinical activities in the hospitals. A cross-sectional study was conducted among 417 final year medical students from Universiti Kebangsaan Malaysia (UKM), University Malaya (UM) and Universiti Putra Malaysia (UPM). The aims of the study were to determine the incidence of cases and episodes of needle stick injury among them in the past year. This study was also done to find out the factors that might be associated with the occurrence of this problem. The factors were sociodemographic factors, duration of exposure, level of knowledge of blood-borne diseases and Universal Precaution, perception of risk of blood-borne diseases and level of practice of Universal Precaution. The incidence of needle stick injury among medical students was 14.1% (59 cases). The total number of episodes of needle stick injury was 87 and the incidence of episodes among respondents was high i.e. 20.9%. The highest incidence of episodes of needle stick injury occurred in Obstetric & Gynaecology postings, followed by Medicine and Surgery. For clinical procedures, venepuncture had the highest incidence followed by setting up drips and giving parenteral injections. The results showed the students who had needle stick injury (cases) had lower scores in the practice of Universal Precautions than non-cases (p<0.05). There was a significant association between the level of practice of Universal Precautions and the number of episodes of needle stick injury, i.e. the higher the score for the practice of Universal Precautions, the lower the number of episodes (β=-2.03 × 10^-2, p<0.05). This study showed that medical students are at risk of needle stick injury and blood-borne infections during their clinical activities while performing procedures on patients especially for those who were poor at practising Universal Precautions. Therefore some preventive measures should be taken by the management of the universities and medical students to avoid the occurrence of these problems.

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We investigated the relationship between burnout and communication skill training among Japanese hospital nurses to improve the mental health of human service workers. The subjects were forty-five registered nurses referred to a self-expression skill intervention program by their section superiors, with each superior choosing from two to five nurses. The hospital was located in the Kyushu area and staffed by about four hundred nurses. The subjects were divided into an intervention group (19 nurses) and a reference group (26 nurses). The intervention group received the communication skill training in July and August, 2001. The communication skill training was carried out in accordance with the assertiveness training (AsT) precepts of Anne Dickson. In June, 2001, we delivered a set of questionnaires including age, gender, working years, a burnout scale, and a communication skill check-list as a baseline survey. The baseline questionnaires were returned at the end of June, 2001. In January, 2002, we delivered the same questionnaire again to the two groups and collected them at the end of the month. Excluding the only male and insufficient answers, twenty-six nurses (58%) returned complete answers in the initial and subsequent surveys. We found that the personal accomplishment and the two communication skills such as “accepting valid criticisms” and “negotiation” of the intervention group had improved significantly five months after the training as compared with that of the reference. Our results implied that communication skill training might have a favorable effect on burnout among Japanese hospital nurses.

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A retrospective analysis of the poisoning calls received by the National Poisons Information Centre (NPIC) showed a total of 2,720 calls during a period of three years (April 1999-March 2002). Poisoning in children was reported in 995 calls (36.6%). The age ranged from less than 1 yr to 18 yr and the age groups involved were divided into four categories (0-6 yr, >6-12 yr, >12-16 yr, >16-18 yr). The most vulnerable age group included children from less than one year to 6 yr old. Males outnumbered females (M=628, F=367). Although the accidental mode was the commonest (79.7%), intentional attempts were also noticed (20.2%) in the >12-16 yr and >16-18 yr age groups. In the majority of cases, the route was oral (96.8%) followed by dermal exposure (3.2%) comprising bites and stings. Various types of agents belonged to classes of household products (47.0%), drugs (21.8%), industrial chemicals (7.9%), agricultural pesticides (9.1%), bites and stings (3.2%), plants (1.5%), miscellaneous products (5.3%) and unknown products (4.0%). The incidence of poisoning was highest due to household products comprising mainly pyrethroids, parad/thermometer mercury, rodenticides, phenyl, detergents and corrosives, etc. Poisoning due to drugs mainly included anticonvulsants, thyroid hormones, benzodiazepines, analgesics and oral contraceptives. Among the agricultural pesticides aluminium phosphide was the most commonly consumed, followed by organochlorines and organophosphates, etc. Paint thinners were common among industrial chemicals. Bites and stings were mainly snake bites and scorpion stings. Poisoning due to plants was low and Datura was commonly ingested. Although these data may not give an exact picture of the incidence rate in our country, due to underreporting of calls to the Centre and because the actual incidence might be higher or even variable, but they do give the trend in India, indicating that a strong emphasis should be placed on a prevention campaign which can at least reduce the occurrence of accidental pediatric poisoning.

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