Serum, human, exposure

Applicators, mixers, loaders, and others who mix, spray, or apply pesticides to crops face potential dermal and/or inhalation exposure when handling bulk quantities of the formulated active ingredients. Although the exposure periods are short and occur only a few times annually, an estimate of this exposure can be obtained by quantifying the excreted polar urinary metabolites. Atrazine is the most studied triazine for potential human exposure purposes, and, therefore, most of the reported methods address the determination of atrazine or atrazine and its metabolites in urine. To a lesser extent, methods are also reported for the analysis of atrazine in blood plasma and serum. 

Information regarding human exposures to dimethylhydrazine are limited to a few case reports. Although case reports provide qualitative data regarding signs and symptoms of exposure, no exposure concentration data or precise exposure duration data were reported. Signs and symptoms of exposure included respiratory effects, nausea, vomiting, neurologic effects, pulmonary edema, and increased serum enzyme levels (reviewed in Trochimowicz et al. 1994). 

In order to assess the potential extent of human exposures and health effects, members of dairy farm families who consumed raw dairy products known to be contaminated with heptachlor epoxide were studied (Stehr-Green et al. 1986). These individuals and an unexposed urban reference population were compared with regard to serum pesticide levels and liver toxicity. The farm family members had significantly higher mean serum levels of heptachlor epoxide (0.81 0.94 ppb), oxychlordane (0.70 0.75 ppb), and transnonachlor (0.79 0.60 ppb) than the unexposed population. This study is limited because exposure level, duration, and frequency of exposure are not known. There was no increase in prevalence of abnormal liver function tests in the dairy farm families... 

To evaluate human exposure to phthalates and their substitutes, the main approaches investigate either the levels of chemicals in matrices relevant for human exposure (indoor air, dust, food and packages, etc.) or the levels of parent and metabolite compounds in human samples (serum, urine, or breast milk). An overview of phthalate and nonphthalate plasticizers together with their metabolites commonly reported in literature is presented in Table 5. The half-lives for the most of these compounds are already established and therefore, by evaluating the levels of their metabolites in human urine, the levels of their parent compounds may be... 

Biological monitoring data are available primarily from occupational settings. Determination of nickel in the urine, feces, serum, hair, and nasal mucosa has been used to demonstrate human exposure to nickel compounds (Angerer and Lehnert 1990 Bencko et al. 1986 Bemacki et al. 1978 Elias et al. 1989 Ghezzi et al. 1989 Hassler et al. 1983 Toijussen and Andersen 1979). Serum and urine levels of nickel have been the most often studied. 

Monitoring human exposure to fluoride can be accomplished with varying degrees of accuracy through the analysis of several biological fluids and tissues. The concentrations of fluoride in plasma, serum and urine have been considered... 

Neurological Effects. Little information was available to determine the neurotoxicity or the mechanism of neurotoxicity of HDI after inhalation, oral, or dermal exposure. Headache was reported in only one human exposure case (Malo et al. 1983). Neurotoxic effects (convulsions) may occur in laboratory animals if concentrations reaeh high levels in the air (Haskell Laboratory 1961) however, sinee HDI is metabolized quickly in a biological matrix (Berode et al. 1991), little intaet HDI is expected to reach the nervous tissue to elicit a toxic response, except possibly at very high eoneentrations. No neurological effects have reported in laboratory animals, or in hiunans exposed chronieally to low concentrations of HDI (Mobay Corporation 1989). HDI, in addition to other isocyanates, have been shown to inhibit acetylcholinesterase in human erythrocytes (Dewair et al. 1983), human serum acetylcholinesterase (Brown et al. 1982), as well as equine serum, bovine erythrocyte, and eel acetylcholinesterase (Brown et al. 1982). 

The major action resulting from human exposure to diazinon is the inhibition of cholinesterase activity (refer to Section 2.4 for discussion). Two pools of cholinesterases are present in human blood acetylcholinesterase in erythrocytes and serum cholinesterase (sometimes referred to as pseudocholinesterase or butyrlcholinesterase) in plasma. Acetylcholinesterase, present in human erythrocytes, is identical to the enzyme present in neural tissue (the target of diazinon action) while serum cholinesterase has no known physiological function. Inhibition of both forms of cholinesterase have been associated with exposure to diazinon in humans and animals (Coye et al. 1987 Edson and Noakes 1960 Soliman et al. 1982). Inhibition of erythrocyte, serum, or whole blood cholinesterase may be used as a marker of exposure to diazinon. However, cholinesterase inhibition is a common action of anticholinesterase compounds such as organophosphates (which include diazinon) and carbamates. In addition, a wide variation in normal cholinesterase values exists in the general population, and there are no studies which report a quantitative... 

Thus, human exposure to PCBs in Japan (Yusho accident) and China has been associated with increased respiratory infections and decreased levels of immunoglobulins in serum. In animals exposed to these compounds, there is atrophy of both primary and secondary lymphoid organs, lower circulating immunoglobulins, and decreased antibody responses after exposure to antigens. Similarly, the exposure of both humans and farm animals to polybrominated biphenyls, which occurred in Michigan in 1973, resulted in depressed immune responses. 

Few studies have investigated the reproductive toxicity of DEHP in female animals. When female mice were exposed to a dietary dose of 420 mg/kg/day DEHP for 105 days and mated with unexposed males, combined weights of the ovaries, oviducts, and uterus were reduced, and no litters were produced. When female mice exposed to 14 or 140 mg DEHP/kg/day were mated with males given these same doses, there was a dose-related decline in the number of litters, live pups per litter, and live pup weight. Short-term gavage exposure to a very high level of DEHP (2,000 mg/kg/day), particularly with respect to possible human exposure, had clear effects on estradiol synthesis, manifested as decreased serum estradiol levels and anovulatory cycles and polycystic ovaries, in female rats. These data indicate that oral exposure to DEHP can affect reproductive processes in female rodents. 

Renal Effects. Renal congestion has been noted at autopsy after a fatal human exposure by inhalation (Winek and Cullom 1971). No adverse renal effects were observed in animals administered benzene orally for acute, intermediate, or chronic durations (Exxon 1986 Hsieh et al. 1990 Huff et al. 1989 NTP 1986). Administration of benzene, 438 mg/kg intraperitoneally or 877 mg/kg subcutaneously, to male and female rats for 10 consecutive days resulted in a decrease in serum uric acid (Ahmad et al. 1994). Based on these limited data, adverse renal effects do not appear to be of primary concern with regard to human health after exposure to benzene occupationally, in the environment, or at hazardous waste sites. 

Letkeman P. (1996) Computer-modelling of metal speciation in human blood serum. J. Chem. Educat. 73, 165—170. Lioy P. J. (1990) Assessing total human exposure to contaminants. Environ. Sci. Technol. 24, 938—945. 

Metabolic Effects. Decreases in serum triglycerides have been noted in rats (Levine et al. 1981, 1990). It is unknown whether this effect may be significant for human exposure to RDX. 

Vanadium concentrations in blood, serum or urine are used as a biological indicator of exposure to vanadium. Urine and serum are the specimens with widest application and greatest practicability for monitoring human exposure to vanadium compounds, but urine is preferred as an indicator medium. Blood vanadium appears to be a less sensitive indicator than urinary vanadium, partly because the differences in concentrations are hardly appreciable at low levels of exposure with the analytical methods available (Alessio et al., 1988). 

This method is widely used in the analysis of human blood samples in the United States. A screening analysis in which LC-MS with ESI is applied to human blood serum after the same pretreatment has been reported. CDC has reportedthe analysis of 13 PFCs in blood and maternal milk with automated SPE and LC-MS/MS. In Japan, environmental monitoring of PFCs has been performed. However, investigation of human exposure has seldom been done. Currently, LC-MS or LC-MS/MS is to determine PFCs in biological samples. However, it is said that the use of LC-MS/MS that has high accuracy is favorable to correctly evaluate human exposure. As sample pretreatment methods, the liquid-liquid... 

---