Exposure, serum

Exposure Serum level Body burden3 Elimination... 

On the day of experiment, trypsinize the adherent cell cultures (see Note 1). After washing twice by centrifugation (5 min, 210 x g), resuspend the cells in the exposure serum-free culture medium, e.g., DMEM supplemented with 25 mM HEPES (DMEM-H). Count viable cells and adjust the cell density to a range of... 

Polhuijs, M., Langenberg, J.P., Benschop, H.P. (1997a). A new method to detect organophosphate exposure serum analysis of victims of Japanese terrorists. In m-CB Medical Treatment Symposium, May 26-30, 1997, Hradec Kralove, Abstracts, p. 25. 

Serum is the least useful specimen for identifying As exposure. Serum concentrations of As are elevated for only a short time after administration, after which As is bound to protein and rapidly disappears into the large body phosphate pool, as the body treats As hke phosphate, incorporating it wherever phosphate would be incorporated. Absorbed As is rapidly circulated and distributed into tissue storage sites. Abnormal serum As concentrations are detected for only a few hours (<4 hours) after ingestion. This test is useful only to document an acute exposure when the As is likely to be >100ng/mL for a short period of time. Normally, serum As is <35ng/mL. 

Erythroqde protoporphyrin concentrations are not a sensitive indicator of low-concentration Pb exposure but are definitive markers for Pb overdose an er)rthrocyte protoporphyrin concentration greater than 60(J.g/dL is a significant indicator of Pb exposure (see Chapter 32). Serum ALAD concentrations are also a useful indicator for medium to high concentrations of Pb exposure however, they do not correlate with low concentrations of Pb exposure. Serum Pb analysis is of very limited utility, because Pb concentrations are abnormal only for a short period of time after exposure. Normally the hair Pb content is lower than 5ug/g hair Pb concentration greater than 25 lg/g mdicates severe Pb exposure. Quantification of urine excretion rates either before or after chelation therapy has been used as an indicator of Pb exposure. However, blood Pb levels have the strongest correlation with toxicity. 

In humans, clinical studies of PCB workers reported associations between increased serum levels of liver-related enzymes, lipids, and cholesterol and serum PCBs. Studies of people exposed to PCBs by ingestion of contaminated fish in Triana, Alabama or contaminated rice oil in the Yusho or Yu-Cheng incidents have reported increases in serum levels of some liver enzymes characteristic of microsomal enzyme induction or liver damage, but these effects cannot be attributed solely to PCBs due to the mixed chemical nature of the contaminated fish and heated rice oil exposures. Serum cholesterol, but not triglycerides, was increased in consumers of contaminated fish, whereas increased serum triglycerides, but not cholesterol, were associated with Yusho and Yu-Cheng exposure. 

General Population Exposures. Serum cholesterol and triglycerides were increased in individuals with elevated serum PCB levels who had resided near waste sites for 5 years (Steer-Green et al. 1986a,... 

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