Air Pollutants, Occupational ; adverse effects ; analysis ; Dust ; analysis ; Environmental Monitoring ; instrumentation ; methods ; Humans ; Industry ; Inhalation Exposure ; statistics & numerical data ; Maximum Allowable Concentration ; Occupational Exposure ; statistics & numerical data ; Quartz

Environmental Monitoring ; methods ; Inhalation Exposure ; Occupational Exposure ; analysis ; Workplace

Electromagnetic Fields ; Environmental Exposure ; Humans ; Radiation Dosage ; Threshold Limit Values

Emergencies ; Environmental Exposure ; standards ; Humans ; Maximum Allowable Concentration

OBJECTIVETo study the biological exposure index of carbon disulfide in China.

METHODSHigh-performance liquid chromatography (HPLC) was used to detect the levels of 2-thiothiazolidine-4-carboxylic acid (TTCA) in the urine of the workers after working shift end, Gas chromatography was used to detect the concentrations of the carbon disulfide in the workplace air. The relationship between the urine TTCA levels and the concentrations of the carbon disulfide was analyzed, the biological exposure index and judgement result from PC-TWA were compared.

RESULTSThe levels of TTCA in urine of workers occupationally exposed to carbon disulfide were closely and positively related with the concentrations of the carbon disulfide in the workplace air. The regression equation was Y = 0.265X - 0.165, The biological exposure index of carbon disulfide were calculated by regression equation according to occupational exposure limits of carbon disulfide in China.

CONCLUSIONThe biological exposure index of CS(2) in China might be revised for 1.2 mg/g Cr.

Carbon Disulfide ; analysis ; Chromatography, Gas ; Environmental Monitoring ; Humans ; Occupational Exposure ; analysis ; Thiazolidines ; urine ; Threshold Limit Values ; Workplace

This study was conducted to evaluate the relationships between the environmental exposure and biological monitoring among workers exposed to metallic mercury. We interviewed each workers to get the medical history including previous hazardous occupational history we measured the respiration rate and tidal volume of each worker in order to calculate the 8-hour inhaled mercury of workers. And we wanted to evaluate the effect of exposure duration to mercury concentrations in blood and urine as biologic exposure indices of metallic mercury. The regression and correlation analysis were done to the relationships of 8-hour inhaled mercury are mercury in blood and urine. The results were as follows; 1. The subjects were 35 fluorescent lamp manufacturing workers. The mean age of subjects was 24.8 years old, and the mean work careers of workers was 1.19 years. 89% of the total was consisted man. 2. The correlation coefficients between 8-hour inhaled mercury and mercury in blood and urine were higher than that of only considered air mercury concentration. 3. The correlation coefficients of 8-hour inhaled mercury and mercury in blood and urine were above 0.9 in workers who had exposed to mercury more than 1 year. 4. The R-square value and -value of regression analysis between the 8-hour inhaled mercury and mercury inn blood and urine was also higher in workers who had exposed to mercury over 1 year than in workers who had less than 1 year working experience. The important results or this study were that relationships between the 8hr-inhaled mercury and mercury in blood and urine was very high than that with air mercury concentration only. And the results were very apparent when considering workers 1 year or more. Therefore we concluded that the work career and respiratory volume of each individuals should be considered in evaluation the results of biological monitoring of workers exposed to metallic mercury.
Environmental Exposure ; Environmental Monitoring ; Inhalation* ; Respiratory Rate ; Tidal Volume

Electromagnetic Fields ; adverse effects ; Environmental Exposure ; adverse effects ; Humans ; Occupational Exposure ; adverse effects ; Radiation Monitoring ; methods ; Risk Assessment

OBJECTIVETo investigate atmospheric mercury concentration in the workplace and urinary mercury concentration in workers exposed to mercury in a thermometer factory, and to determine the levels and influencing factors of urinary Β₂-microglobulin (Β₂-MG) and retinol-binding protein (RBP) in these workers.

METHODSAn occupational health survey of the workplace was completed according to relevant national occupational health standards. Questionnaire survey and occupational health examination were conducted in 178 workers exposed to mercury in the factory. Statistical analysis was accomplished using SPSS 19.0.

RESULTSIn the workplace, atmospheric mercury concentration was out of limits at seven of eight detection points expressed by short-term exposure limit; it was out of limits at all the eight detection points shown by time-weighted average. Statistically significant difference in atmospheric mercury concentration was found among different detection points (F = 138.714, P < 0.001). The geometric mean of urinary mercury concentration measured in 154 workers was 171.607 µg/g. There were 127 workers with urinary mercury concentration exceeding the standard (82.5% over-standard rate). Significant difference in urinary mercury concentration was shown in the workers among different positions (χ² = 44.531, P < 0.01). Urinary mercury concentration was positively correlated with atmospheric mercury concentration (r = 0.624, P < 0.01). The mean urinary Β₂-MG level measured in 148 workers was 0.142 mg/L, and seven workers had urinary Β₂-MG levels greater than 0.3 mg/L (4.7% abnormal rate). The mean urinary RBP level measured in 153 workers was 0.485 mg/L, and 19 workers had urinary RBP levels greater than 0.7 mg/L (12.4% abnormal rate). Ordinal logistic regression showed that age >34 years (OR = 4.88, 95%CI: 2.24∼10.62) and length of service >15 years (OR = 2.50, 95%CI: 1.06-5.92) were risk factors for increased urinary Β₂-MG level. Age >45 years (OR = 7.52, 95%CI: 2.50∼22.65) was a risk factor for increased urinary RBP level.

CONCLUSIONIn the thermometer factory under study, atmospheric and urinary mercury concentrations both seriously exceeded the standards, which were harmful to the health of workers. High atmospheric mercury concentration, old age, and long length of service were risk factors for increased urinary Β₂-MG and RBP levels in workers exposed to mercury.

Adult ; Environmental Exposure ; Humans ; Kidney ; drug effects ; Kidney Diseases ; chemically induced ; Mercury ; analysis ; toxicity ; Occupational Exposure ; Risk Factors ; Threshold Limit Values ; Time Factors ; Workplace

OBJECTIVESTo investigate intensity of extremely low frequency magnetic field (ELFMF) emitted from cathode-ray tubes (CRT) of monitors in various directions and to find ways to avoid its influence.

METHODSTwo hundred CRT monitors and 10 monitors with liquid-crystal display (LCD) were selected. Their ELFMF was detected for three times in front of the monitor at an interval of every 5 cm from 0 cm to 50 cm, as well as at various directions from the monitor.

RESULTSIntensity of ELFMF significantly attenuated at regular operating position (30 - 40 cm) from 0 cm to 50 cm in front of both 38 cm and 43 cm CRT monitors (P < 0.05). Intensity exceeded 0.4 microT both within 15 cm and 10 cm in front of 38 cm and 43 cm monitors. The highest intensity was found at the upright top position of both kinds of monitors, 9.54 microT for 38 cm monitor and 6.38 microT for 43 cm one, respectively.

CONCLUSIONSIt is suggested to keep away from monitor screen as possible when operating a computer, to reduce unnecessary operation in front of a monitor screen, and to shorten operating time. To avoid more hazards from interactive interference between computers, it is necessary to increase distance between monitors.

Computers ; Electromagnetic Fields ; adverse effects ; Environmental Exposure ; adverse effects ; Equipment Safety ; Humans ; Occupational Exposure ; adverse effects ; Radiation Monitoring ; methods ; Risk Assessment

OBJECTIVETo determine the risk factors in the development of central nervous system (CNS) congenital malformations.

METHODSA hospital-based 1:2 matched case-control study was conducted. Each case was matched with two normal controls on sex and residential area, date of birth, within half a year. By means of simple and multivariable conditional logistic regression, 48 factors were analyzed.

RESULTSMaternal exposure to pesticide or having cold with fever, family history of positive congenital malformations, preference eating pickled vegetables, negative life events, large consumption of meat, eggs, beans and milk during pregnancy and paternal exposure to poisonous chemicals were significantly associated with CNS congenital malformations, with odds ratios 16.471, 12.621, 10.246, 7.274, 3.730, 0.229, 5.616, respectively.

CONCLUSIONSMaternal exposure to pesticides, cold with fever, positive congenital malformations family history, preference of eating pickled vegetables, negative life events during pregnancy, and paternal exposure to poisonous chemicals were the key risk factors contributing to CNS congenital malformations, while maternal exposure to big consumption of meat, eggs, beans and milk during pregnancy was protective factors that reducing CNS congenital malformations.

Adult ; Case-Control Studies ; China ; epidemiology ; Environmental Exposure ; Female ; Humans ; Male ; Maternal Exposure ; Nervous System Malformations ; epidemiology ; etiology ; Neural Tube Defects ; epidemiology ; etiology ; Paternal Exposure ; Pregnancy ; Risk Factors