Biomarkers biological material

Blood is a better indicator of exposure to chlordecone than is saliva (Borzelleca and Skalsky 1980 Skalsky et al. 1980). Chlordecone has been detected in saliva of humans only in trace amounts and in rats at concentrations three to four times lower than in blood (Guzelian et al. 1981 Skalsky et al. 1980). Peak chlordecone concentrations occurred within the first 24 hours of exposure therefore, the period of utility of saliva as a biomarker is limited. The movement of chlordecone from the blood into the saliva is one of passive diffusion and is not concentration dependent (Borzelleca and Skalsky 1980 Skalsky et al. 1980). Thus, blood is a better biological material than saliva for monitoring exposure. 

No information was located concerning on-going studies for improving methods of analysis of hexachlorobutadiene, its metabolites, or other biomarkers of exposure and effect to hexachlorobutadiene in biological materials or environmental samples. 

Methods for Biomarkers of Exposure. No methods are available for the analysis of isophorone biomarkers of exposure in biological materials. If a method for the determination of the level of a specific biomarker were available in a biological medium, it could be used to indicate the level of exposure and the possible resultant health effect. 

Methods for Determining Biomarkers of Exposure and Effect. Existing methods of measuring levels of silver in blood, urine, feces, hair, and tissues are extremely sensitive and can measure levels in the low ppm to ppt. These methods are accurate and reliable and can be used to measure both background levels of exposure and levels at which biological effects occur. No additional analytical methods for determining trace levels of silver in biological materials are needed. 

Methods for Determining Biomarkers of Exposure and Effect. As discussed above, the presence of radium in biological materials is usually determined by virtue of its radioactivity. Methods available for the determination of radioactivity in biological materials include alpha spectroscopy and gamma spectrometry, which is more convenient, but generally less sensitive, than alpha spectroscopy (Joshi 1987). It would be useful to have additional data on the sensitivity and accuracy of the methods that are currently in use. 

Biosensors Analytical devices that incorporate biological material or a material mimicking biological membranes associated with or integrated within a physical-chemical transducer or transducing system. Biosensors are based on biochemical biomarker responses at the suborganism level. 

As already stated, the source of biological material is also important either due to its accessibility (i.e., noninvasive nature) or due to the fact that the analytes to be measured are restricted to certain locations. Biomarkers can be detected in all biological entities (i.e., fluids, gases, and tissues), and depending on what is to be measured each biological source has a specific niche. For example the fact that alcohol is excreted in the lung, combined with the convenience of using exhaled air, has been exploited for many years in the breathalyzer test as an indirect measurement of blood alcohol levels [5 ]. Stool is commonly used for the detection of parasites and infections. Tears have been proposed to detect and treat ocular toxicity [6], Urine has also been used extensively to measure both renal and non-renal injuries. However, for the most part, blood (serum or plasma) and urine are the most utilized sources. 

This chapter presents different analytical procedures, which can be used to quantify the concentration of cadmium and its metabolites in biological material as well as biomarkers of effect after cadmium exposure. 

Pentachlorophenol concentrations in urine and serum can be used as biomarkers of internal dose (Colosio et al., 1993a). PCP concentrations up to about 30 mg/L were detected in urine samples of exposed workers, while concentrations lower than 0.3 mg/L were detected in the general population. The presence of PCP in biological samples of the general population is attributable to indoor exposure to the compound released from treated materials (furniture, leather, paints, etc.). 

Aflatoxins, for example, Bj (36) and their biological markers have been determined using ESI (90,91). Aflatoxins B1 B2, G1 G2 were analyzed in food samples by LC/ESI/MS using a 150 x 2-mm C18 column eluted isocratically with acetonitrile-MeOH-10 mM NH4OAc (2 16 15) (90). The positive ESI spectra were dominated by the protonated molecules, which were used for SIM. The method enabled concentrations down to lppb to be detected in various food materials. LC/ESI/MS/MS has been used for the detection of aflatoxin DNA adducts as urinary biomarkers of exposure (91). 

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