Air Pollutants, Occupational ; toxicity ; Humans ; Occupational Exposure ; adverse effects ; Welding

OBJECTIVETo understand the exposed positions and levels of indium and its compounds in manufacture of liquid crystal displays, and to evaluate the degree of occupational hazard from indium and its compounds.

METHODSOn-site investigation of occupational health, occupational hazard monitoring, and occupational health examination were used to evaluate the degree of occupational hazard from indium and its compounds in three manufacturers of liquid crystal display panel in Shenzhen, Guangdong, China.

RESULTSThe time-weighted average (TWA) and short-term exposure limit (STEL) concentrations of indium and its compounds to which sputtering machine operating positions were exposed were less than 0.002~0.004 mg/m³ and 0.006~0.007 mg/m³, respectively, both of which complied with the National Hygienic Standard (PC-TWA = 0.1 mg/m³; PC-STEL = 0.3 mg/m³); the TWA and STEL concentrations of indium and its compounds to which grinding positions were exposed were 0.114~2.98 mg/m³ and 0.31~10.02 mg/m³, respectively, both of which exceeded the National Hygienic Standard with the highest concentration 33-fold higher than the standard. No significant health damages were found in exposed workers according to the results of occupational health examination.

CONCLUSIONThe grinding positions are the key to the control of occupational hazard from indium and its compounds in manufacture of liquid crystal display panel. The workers should be equipped with the anti-particulate full-face respirator, which is an effective way to prevent occupational hazard from indium and its compounds.

Air Pollutants, Occupational ; toxicity ; China ; Data Display ; Humans ; Indium ; toxicity ; Liquid Crystals ; Occupational Exposure ; analysis ; Occupational Health ; Risk Assessment ; Threshold Limit Values

OBJECTIVETo establish the method of detecting the concentrations of chlorpyrifos in air of workplace with high performance liquid chromatographic (HPLC).

METHODSAccording to standards of methods for determining the chemical substances in workplace air, chlorpyrifos in the air was collected by silicone tube, then dissolved by acetonitrile and determined by high performance liquid chromatography with UV-detector.

RESULTSThere was a linear relationship within the range of 0 ∼ 10.0 µg/ml, and regression equation was y = 5206.1x - 104.7, correlation coefficient was 0.9999, the detection limit was 0.006 µg/ml. The lowest detected concentration was 0.001 mg/m(3) (sampling volume 4.5 L). The average recoveries was 98.3% ∼ 102.5%. The within-run precision was 1.96% ∼ 4.39%, the between-run precision was 2.76% ∼ 5.87%. The desorption efficiencies were 99.0% ∼ 103.3% and the sampling efficiencies were 94%. The samples in silicone tube could be stored for 15 days at room temperature.

CONCLUSIONThe present method could meet with the requirements of Guide for establishing occupational health standards-Part 4 Determination methods of air chemicals in workplace and be feasible for determination of chlorpyrifos in workplace air.

Air Pollutants, Occupational ; analysis ; Chlorpyrifos ; analysis ; toxicity ; Chromatography, High Pressure Liquid ; methods ; Limit of Detection ; Reproducibility of Results ; Workplace

OBJECTIVETo assess the effect of benzene on sperm DNA.

METHODSTwenty-seven workers exposed to benzene for over two years were included in the experiment group and 35 unexposed ones were chosen as controls. Damage by benzene on sperm DNA was detected by modified single cell gel electrophoresis (SCGE).

RESULTSThe benzene concentration in the air of the workplace of the exposed workers was (86.49 +/- 2.83) mg/m3, twice that of the national maximum allowance (40 mg/cm3). Urinary, trans-muconic acid in the exposed group was (1.40 +/- 0.62) mg/L (n = 27), significantly higher than that of the controls [(0.82) +/- 0.16) mg/L, n = 35]. After SCGE, the percentage of head DNA in the exposed group [(70.18% +/- 7.36%, n = 13 ] was significantly lower than that of the controls (90.62% +/- 2.94%, n = 16), P < 0.001.

CONCLUSIONHigher concentration of benzene could cause damage to the sperm DNA of the workers exposed to it.

Adult ; Air Pollutants, Occupational ; analysis ; Benzene ; analysis ; toxicity ; Comet Assay ; DNA Damage ; drug effects ; Humans ; Male ; Occupational Exposure ; Spermatozoa ; drug effects ; Surveys and Questionnaires

OBJECTIVETo explore the hepatic toxicity and the exposure biomarkers of N, N-Dimethylacetamide.

METHODSOne hundred forty five objects were chosen by stratified random sampling method. The investigation was performed using questionnaire and physical examination. The air concentrations of DMAC in the workshops were monitored. The urine samples were collected and analyzed after work everyday or at the weekend. The correlation between the air concentrations of DMAC in the workshops and the concentrations of urinary NMAC wee analyzed by regression.

RESULTSThe air concentration of DMAC in the spinning workshop was higher than others. The morbidity of abnormal hepatic function was 12.4%, 61.1% of workers with abnormal hepatic function appeared in one year after exposure to DMAC in the workshops ( r=0.44, P<0.01).

CONCLUSIONThe abnormal heptic function was found in workers exposed to DMAC for short period. The concentration of urinary NMAC can serve as the exposure biomarker of DMAC.

Acetamides ; toxicity ; urine ; Adolescent ; Adult ; Air Pollutants, Occupational ; analysis ; Biomarkers ; urine ; Environmental Monitoring ; Humans ; Liver Function Tests ; Male ; Middle Aged ; Occupational Exposure ; Surveys and Questionnaires ; Workplace ; Young Adult

OBJECTIVETo investigate whether asbestosis is a risk factor for mortality of lung cancer.

METHODSA fixed cohort study was established in an asbestos plant in Chongqing, China, and followed up for 30 years from the beginning of 1972. Basic personal information on life state, cause of death, and diagnosis of asbestosis was collected. Multiple logistic regressions were applied to analyze risk factors.

RESULTSDuring the 30-year follow-up, 584 male workers constituting a total of 14,664 person-years were monitored and data were analyzed. Among them, 203 (34.8%) died and the mortality rate was 13.8 per 1000 person-years, cancer accounting for 37.4%. Excess risks were observed for lung cancer (OR = 3.72) and nonmalignant respiratory diseases (OR = 2.73) among workers with asbestosis. High-exposure level was another risk factor for lung cancer (OR = 3.20). Workers with category II of asbestosis demonstrated a higher OR of both lung cancer and nonmalignant respiratory diseases than those with category I of asbestosis.

CONCLUSIONHigh asbestos exposure level and asbestosis were the risk factors for death of lung cancer and nonmalignant respiratory diseases. Asbestosis is an independent risk factor for lung cancer among Chinese workers exposed to chrysotile, the risk increases with the increasing profusion of opacities of lung.

Adult ; Air Pollutants, Occupational ; toxicity ; Asbestos, Serpentine ; toxicity ; Asbestosis ; complications ; mortality ; Chemical Industry ; China ; epidemiology ; Humans ; Lung Neoplasms ; chemically induced ; mortality ; Male ; Occupational Diseases ; chemically induced ; mortality ; Occupational Exposure ; adverse effects ; Odds Ratio ; Risk Factors

Adult ; Age Factors ; Air Pollutants, Occupational ; toxicity ; Humans ; Male ; Middle Aged ; Occupational Exposure ; Police ; Pulmonary Diffusing Capacity ; physiology ; Pulmonary Ventilation ; physiology ; Respiratory Function Tests ; Smoking ; adverse effects ; Vehicle Emissions ; toxicity

OBJECTIVETo investigate the relationship between genetic polymorphism of dopamine β-hydroxylase (DBH) and manganese-induced nerve injury.

METHODSIn a cross-sectional study, 402 electric welders who had worked over one year in relatively fixed sites were recruited, and the concentration of manganese in which they worked was stable. These samples was divided into high exposure group (CEI > 1) and low exposure group (CEI < 1) by CEI. Between the two groups, the groups were divided into abnormal group and normal group according to the result of neurologic check (there were 81 workers with abnormal neurological dysfunction in high exposure group and 28 workers in low exposure group, P < 0.05). Polymorphism of DBH gene was analyzed with polymerase chain reaction-restriction fragment length polymorphism.

RESULTSThe distribution of A2A2 genotype and A2 allele of DBH was significantly different. In high exposure group, the distribution of A2A2 genotype and A2 allele of DBH in abnormal group was significantly wider than in normal group (A2A2 genotype, OR = 1.248, P < 0.05, A2 allele, OR = 1.103, P < 0.05). In low exposure group, the distribution of A2 allele of DBH in abnormal group was significantly wider than in normal group (OR = 1.176, P < 0.05).

CONCLUSIONThe individuals who carry A2A2 genotype and A2 allele of DBH have increased risk of neurological dysfunction after explosion to manganese for a certain time, which suggests that polymorphism of DBH (intron 5 Taq I) would play a great role in hereditary susceptibility of neurological dysfunction cause by manganese.

Adult ; Air Pollutants, Occupational ; analysis ; toxicity ; Cross-Sectional Studies ; Dopamine beta-Hydroxylase ; genetics ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Male ; Manganese ; analysis ; toxicity ; Middle Aged ; Nervous System Diseases ; genetics ; Polymorphism, Single Nucleotide ; Welding ; Young Adult

BACKGROUND: Volatile organic compounds (VOCs) in concentrations found in both the work and home environments may influence lung function. We investigated the prevalence of airway responsiveness in workers exposed to VOCs. METHODS: We used allergic skin tests, nonspecific airway hyperresponsiveness testing and questionnaires to study twenty exposed workers and twenty-seven control subjects. Atopy was defined as a reactor who showed >3+ response to one or more allergens on the skin prick tests. Airway hyperresponsiveness (BRindex) was defined as log [% fall of FEV1/ log (last concentration of methacholine) +10]. RESULTS: The VOC exposed workers, in comparison with the control subjects, tended to have a higher BRindex (1.19+/-0.07 vs. 1.15+/-0.08, respectively). Workers exposed to VOCs with atopy or smoker, as compared with the workers exposed to VOCs with non-atopy and who were non-smokers and the control subjects with non-atopy and who were non-smokers, had a significantly higher BRindex (1.20+/-0.05 vs. 1.14+/-0.06 vs. 1.10+/-0.03, respectively p<0.05). The BRindex was not correlated with atopy, the smoking status or the duration of VOC exposure. CONCLUSIONS: These findings suggest that VOCs may act as a contributing factor of airway hyperresponsiveness in workers exposed to VOCs.
Smoking ; Skin Tests ; Risk Factors ; Questionnaires ; Organic Chemicals/*toxicity ; Occupational Exposure/*adverse effects ; Occupational Diseases/*chemically induced ; Multiple Chemical Sensitivity ; Male ; Korea ; Humans ; Forced Expiratory Volume ; Female ; Chemical Industry ; Case-Control Studies ; Bronchial Hyperreactivity/*chemically induced ; Air Pollutants, Occupational/*toxicity ; Adult

BACKGROUND: Plastic resins are complex chemicals that contain toluene diisocyanate (TDI) and/or trimellitic anhydride (TMA), which cause occupational allergies (OA), including respiratory allergies. Serum IgGs against TDI and TMA have been suggested as potential markers of the exposure status and as exploring cause of OA. Although TDI-specific IgG has been examined for suspected OA, TMA-specific IgG is not commonly evaluated in a urethane foam factory. This study therefore investigated both TDI- and TMA-specific IgGs in suspected OA patients and to evaluate the usefulness of the measurement of multiple chemical-specific IgG measurement for practical monitoring. METHODS: Blood samples were collected from two male workers who developed respiratory allergies supposedly caused by occupational exposure to TDI and/or TMA for the presence of TDI- and TMA-specific IgGs. In addition, blood samples from 75 male workers from a urethane foam factory, along with 87 male control subjects, were collected in 2014 and tested for the same IgGs in 2014. The presence and levels of TDI- and TMA-specific serum IgGs were measured using dot blot assays. RESULTS: We found that controls had mean concentrations of TDI- and TMA-specific IgGs of 0.98 and 2.10 μg/mL, respectively. In the two workers with respiratory allergies, the TDI-specific IgG concentrations were 15.6 and 9.51 μg/mL, and TMA-specific IgG concentrations were 4.56 and 14.4 μg/mL, which are clearly higher than those in controls. Mean concentrations of TDI- and TMA-specific IgGs in the factory workers were 1.89 and 2.41 μg/mL, respectively, and are significantly higher than those of the controls (P < 0.001 and P < 0.026 for TDI- and TMA-specific IgGs, respectively). CONCLUSION The workers suspected of OA showed an evidently high level of TDI- and TMA-specific IgG, and these levels in workers at the urethane foam factory were also significantly higher than those in controls. In conclusion, the measurement of TDI- and TMA-specific IgG among workers using plastic resins is helpful to monitor their exposure status.
Adult ; Air Pollutants, Occupational ; adverse effects ; immunology ; Environmental Monitoring ; Humans ; Immunoglobulin G ; blood ; immunology ; Japan ; Male ; Manufacturing and Industrial Facilities ; statistics & numerical data ; Middle Aged ; Occupational Diseases ; blood ; chemically induced ; Occupational Exposure ; adverse effects ; statistics & numerical data ; Phthalic Anhydrides ; immunology ; toxicity ; Respiratory Hypersensitivity ; blood ; chemically induced ; Toluene 2,4-Diisocyanate ; immunology ; toxicity ; Workforce