Blood samples human exposure application

As with urine, saliva (spumm) is easy to collect. The levels of protein and lipids in saliva or spumm are low (compared to blood samples). These matrices are viscous, which is why extraction efficiency of xenobioties amoimts to only 5 to 9%. By acidifying the samples, extraction efficiencies are improved as the samples are clarified, and proteinaceous material and cellular debris are precipitated and removed. Some xenobioties and their metabohtes are expressed in hair. Hair is an ideal matrix for extraction of analytes to nonpolar phases, especially when the parent xenobioties are extensively metabolized and often nondetectable in other tissues (parent molecules of xenobioties are usually less polar than metabolites). Hair is a popular target for forensic purposes and to monitor drug compliance and abuse. Human milk may be an indicator of exposure of a newborn to compounds to which the mother has been previously exposed. The main components of human milk are water (88%), proteins (3%), lipids (3%), and carbohydrates in the form of lactose (6%). At present, increasing attention is devoted to the determination of xenobioties in breath. This matrix, however, contains only volatile substances, whose analysis is not related to PLC applications. 

Application to Human Exposure (Blood Samples). Blood samples following a suspected human exposure to sulfur mustard have only rarely become available for laboratory analysis. Three of the five known reports involve the analysis of samples that were taken from casualties of the Iran-Iraq War, frozen for several years and then analyzed to verify exposure as methods were developed. The other two published reports are on the analysis of blood samples obtained from three individuals that were casualties of accidental exposures to WWI munitions. 

Application to Human Exposure (Urine and Blood). To date, there have been no reports of the collection of biomedical samples from individuals with suspected lewisite exposure. Samples from such an incident will be critical for confirming the validity of assaying for the biomarkers observed in animal models. Additionally, the biomarkers that have been investigated in animal studies to date have indicated a rapid clearance in urine and less so for blood. This will obviously create severe problems for the retrospective determination of lewisite exposure beyond a few days at most when analyzing urine samples. The blood assay for both bound and free CVAA will potentially provide a longer opportunity for retrospective confirmation of exposure (based on one animal study), but also indicates a substantial decrease (90%) in concentration levels observed over a 10 day period. 

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