2.Investigation of Blood DDT Residual Level in Women and Children in a Pesticide-contaminated Area
Yanrang WANG ; Qian WANG ; Ming ZHANG
Journal of Environment and Health 1992;0(04):-
Objective To investigate the effects of DDT (dichloro-diphenyl-trichloroethane) residuals in the surrounding environment of a pesticide plant on the health of women and children. Methods 50 pairs of children aged 6-10 years and their mothers were investigated during Jan-Jul, 2005. The venous blood samples were collected, the levels of DDT and its 4 metabolites (p,p’-DDE, p,p’-DDT, p,p’-DDD and o,p’-DDT) were determined by GC-ECD and the biochemical indexes of blood were assayed. Each participant completed a questionnaire for information on health history and lifestyle and underwent a prenatal health examination. Results The blood lipid levels were abnormal in 18 percent of mothers. The level of blood total DDT in mothers and children was 8.42 and 11.98 ng/ml respectively. o,p’-DDT and p,p’-DDD were not detected. The level of p,p’-DDE and total DDT in children’s blood was higher than that in the women’s. Conclusion DDT has been accumulated in some degree in the blood of women and children in the area.
6.Evaluation of measurement uncertainty of welding fume in welding workplace of a shipyard.
Chinese Journal of Industrial Hygiene and Occupational Diseases 2015;33(12):934-935
OBJECTIVETo evaluate the measurement uncertainty of welding fume in the air of the welding workplace of a shipyard, and to provide quality assurance for measurement.
METHODSAccording to GBZ/T 192.1-2007 "Determination of dust in the air of workplace-Part 1: Total dust concentration" and JJF 1059-1999 "Evaluation and expression of measurement uncertainty", the uncertainty for determination of welding fume was evaluated and the measurement results were completely described.
RESULTSThe concentration of welding fume was 3.3 mg/m(3), and the expanded uncertainty was 0.24 mg/m(3). The repeatability for determination of dust concentration introduced an uncertainty of 1.9%, the measurement using electronic balance introduced a standard uncertainty of 0.3%, and the measurement of sample quality introduced a standard uncertainty of 3.2%.
CONCLUSIONDuring the determination of welding fume, the standard uncertainty introduced by the measurement of sample quality is the dominant uncertainty. In the process of sampling and measurement, quality control should be focused on the collection efficiency of dust, air humidity, sample volume, and measuring instruments.
Air Pollutants, Occupational ; analysis ; standards ; Gases ; analysis ; Uncertainty ; Welding ; Workplace ; standards
Result Analysis
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