Medical Aspects of Chemical Warfare (2008) - The Black Vault

Medical DiagnosticsNOOCCOH(Figure 22-15). It has been estimated that 3% of BZ inthe body is excreted as the parent compound.Analytical Methods3-Quinuclidinyl BenzilateNOH3-QuinuclidinolHOCOCBenzylic AcidFig. 22-15. Structure of 3-quinuclidinyl benzilate and themain metabolites 3-quinuclidinol and benzylic acid.OHThere are few references to the analysis of BZ inhumans. BZ is frequently used by neuropharmacologistsas a marker, but these methods are often notquantitative. In 1988 the United States began work ondemilitarization of BZ stockpiles. As part of that work,the National Institute of Standards and Technologyand the US Army Research and Development laboratoryat Fort Detrick, Maryland, developed a methodfor monitoring workers. The method was based onGC-MS of the trimethylsilyl (TMS) derivatives andmonitored all three analytes (BZ, benzylic acid, and3-quinuclidinol). Detection limits were 0.5 ng/mL forBZ and 5 ng/mL for the hydrolysis products. 189SAMPLE CONSIDERATIONSGeneralThe following section describes the field collection,shipment, and storage of biomedical samplesaccording to the guidance from the Centers forDisease Control and the United States Army MedicalResearch Institute of Chemical Defense. In mostinstances, blood (serum, plasma) and urine are themost commonly collected samples. Samples to becollected depend upon the specific method requiredby the assay. The information provided in this sectionis intended to provide general guidelines for samplecollection, shipment, and storage and is not intendedto be comprehensive. In all cases, questions regardingspecific procedures to obtain and ship samples shouldbe directed to the receiving laboratory by calling thelaboratory or consulting its Web site before collectingthe sample.UrineThe collection of urine samples should be doneunder the close supervision of a healthcare provideror an unbiased observer to preclude the possibilityof sample tampering. Care should be taken to ensureappropriate handling so as to minimize the chancesfor contamination from the environment or handlingpersonnel. The urine should be collected immediatelyfollowing the suspected exposure or at the earliest possibletime. A midstream urine collection is desirable. Iffollow up is anticipated, additional samples should beobtained at 24 hours. Urine should be collected in cleanurine cups or screw-capped plastic containers that canwithstand freezing temperatures without splitting. Aminimum of 25 to 30 mL should be collected. Urinesamples should be frozen immediately (– 70°C or dryice is preferred).Whole BloodIt is recommended that samples of whole bloodbe handled cautiously from the start of the collectionto maintain integrity and preclude the possibility ofcontamination, tampering, or mislabeling. All samplesshould be collected under the close supervision of ahealthcare provider or physician and witnessed byan unbiased observer if possible. Samples should beobtained as soon as possible following the suspectedexposure. Additional samples may be obtained for followup. Blood should be collected in 5- or 7-mL bloodtubes. Specific methods may require specific types oftubes, such as purple-top (ethylenediamine tetraaceticacid) tubes for plasma or the red-top, unopened,vacuum-fill tubes for serum.For methods that analyze serum or plasma, itis useful to process whole blood samples by centrifugationfollowed by separation of the plasmaor serum from the RBC pellet. The plasma or serumcomponents can then be frozen (– 70°C or dryice is preferred) and stored or shipped on dry ice.When on-site blood processing is not convenient,unprocessed whole blood samples should be storedimmediately at 4°C. Packed RBCs may be stored at4°C or frozen, depending on the properties of theanalyte and the needs of the analytical method tobe performed.739