Body burden, human, work

EWG (Environmental Working Group). 2005. Body Burden The Pollution in Newborns. A Benchmark Investigation of industrial Chemicals, Pollutants, and Pesticides in Human Umbilical Cord Blood. Environmental Working Group and Commonweal [online]. Available http //www.ewg.org/reports/bodyburden2/ [accessed April 17, 2006]. 

The biological half-time of uranium dioxide in human lungs (occupational exposure) at German fuel fabrication facilities was estimated to be 109 days. Body burden measurements of uranium taken from 12 people who handled uranium oxides for 5-15 years were used for this determination. Twice a year for 6 years, a urinalysis was conducted on workers exposed to uranium. In vivo lung counting was performed on the last day before and the first day after a holiday period. Levels of uranium in feces were measured during the first 3 days and the last 3 days of a holiday period and the first 3 days after the restart of work. For some employees, the levels of uranium in feces was measured during 3 days one-half year after the holiday period (Schieferdecker et al. 1985). 

The highest CB-77, CB-126, and CB-169 human body burden has been shown in a French study [163]. These levels are higher than what was reported in Yusho victims [33]. A Dutch study involving 198 mothers [164] and a Swedish study involving 1072 mothers (between 1972 and 1989) [165] are, so far, the largest sampled works. A study in Finland involving 237 mothers [166] indicates that the body burden in Nordic countries is more or less the same and is one of the lowest reported (Table 5). Potentially very toxic CB-126 has been reported in all the studies on human beings. Persistency of CB-169 has been confirmed and the metabolizability of CB-77 has been shown. 

Beck, B.D., Mattuck, R.L., Bowers, T.S., Muir, B., 2001. The development of a stochastic physiologically-based pharmacokinetic model for lead. Sci. Total Environ. 274, 15—19. Bergdahl, I.A., Schulz, A., Gerhardsson, L., Jensen, A., Skerfving, S., 1997. Lead concentrations in human plasma, urine and whole blood. Scand. J. Work Environ. Health 23, 359—363. Bert, J.L., van Dusen, L.J., Grace, J.R., 1989. A generalized model for the prediction of lead body burdens. Environ. Res. 48, 117—127. 

Chelation therapy, therefore, causes a dramatic reduction in the body burden of Pb and causes an equally dramatic reduction in the probability of mortality. Although some work has indicated the psychological benefits of chelation, insufficient research has been conducted on humans or experimental animals to allow a definitive statement about the efficacy of chelation therapy in improving neurobehavioral development following Pb exposure. 

Houlihan, J. Kropp, T. Wiles, R. Gray, S. Cambell, C. 2005. Body burden (the pollution in the newborn). A benehmark investigation of industrial chemicals, pollutants and pesticides in human umbilical cord blood. Environmental Working Group. Available from http //www. ewg. org/reorts/bodybm den2. 

Research with animals can make a valuable contribution to two of the areas discussed earlier outcome measures and exposure assessment. It can indicate which outcome measures are most sensitive to lead effects and which outcomes are insensitive, provide information on the types of processes involved, and inform the choice of outcome measures for studies of children it also provides an opportunity to study the kinetics of lead in relation to the measures of body lead burden most frequently obtained in studies of humans. The effect of chelation therapy on lead levels in the brain, and the relation of these to levels of lead in blood and bone, is another area where animal work can inform studies of children. The limitations of extrapolation from animal data to studies of humans are addressed in the review section of this book. While it is unlikely that the rat provides an adequate model of... 

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