Contamination of tissues

Very low values of proteolysis, such as lay within the range of maximal theoretically possible contamination of tissues with blood, up to an index of 0.4, were found in skeletal muscle, heart, and brain. 

Solutions in contact with polyvinyl chloride can become contaminated with trace amounts of lead, titanium, tin, zinc, iron, magnesium or cadmium from additives used in the manufacture and moulding of PVC. V-Phenyl-2-naphthylamine is a contaminant of solvents and biological materials that have been in contact with black rubber or neoprene (in which it is used as an antioxidant). Although it was only an artefact of the separation procedure it has been isolated as an apparent component of vitamin K preparations, extracts of plant lipids, algae, livers, butter, eye tissue and kidney tissue [Brown Chem Br 3 524 1967]. 

Any waste material (and contaminated cloths, tissues, clothing etc.) must be rendered safe by chemical means or by controlled incineration of dilute solution where practical prior to disposal. 

Serum endosulfan was 4 pg/L at 30 hours after an agricultural pilot was exposed dermally (and probably also by inhalation) for approximately 45 minutes in clothing that was heavily contaminated with endosulfan and methomyl (Cable and Doherty 1999) the dermal exposure level was not estimated and no other measures of tissue levels of endosulfan were obtained. A study by Kazen et al. (1974) has identified endosulfan residues on the hands of workers after relatively long periods free from exposure. Endosulfan residues were identified on the hands of one worker approximately 30 days after exposure and on the hands of one worker who had not used endosulfan during the preceding season. 

A more general example fiom virus vaccine produetion is the rigorous examination of tissue cultures to exclude contamination with infectious agents fiom the sonrce animal or, in the cases of human diploid cells or cells fiom eontinuous cell lines, to detect... 

Tansy CL. 2002. A comparison of contaminants in tissues of mink (Mustela vision) from South Carolina and Louisiana. MS thesis, Clemson University. 

Carpenter et al. 1959), and decreased lactation and delayed estrus in cows after oral ingestion of Fyrquel-150-contaminated plant tissue at unspecified dose levels (Beck et al. 1977). 

Figure 21.1 Decrease in detection sensitivity of the ions originating from proteins by contamination of OTC. Adhering OTC to the tissue section diminishes the detectable peaks, (a) A case in which OTC was used only to support the tissue block, (b) A case in which the tissue block was completely embedded with OTC. Reprinted with permission from Schwartz et al.9...

The types of spoilage caused by bacteria in fruits and vegetables are diverse they include sensory changes, degradation of compounds, and formation of new substances such as acids, volatile compounds, and polymers. For example, the bacteria produce a set of enzymes such as pectinases, cellulases, proteases, and others that causes maceration and softening of tissue. Off-flavor development is common in contaminated tissues, caused by volatile compounds produced by microflora (Jay 1992). 

A prerequisite to pharmacokinetic/pharmacodynamic studies is the availability of a sufficiently selective and sensitive assay. The assay must be capable of detecting and accurately quantifying the therapeutic protein in the presence of a complex soup of contaminant molecules characteristic of tissue extracts/body fluids. As described in Chapter 7, specific proteins are usually detected and quantified either via immunoassay or bioassay. Additional analytical approaches occasionally used include liquid chromatography (e.g. HPLC) or the use of radioactively labelled protein. 

As reported here, adverse effects of chromium to sensitive species have been documented at 10.0 pg/L (ppb) of Cr+6 and 30.0 pg/L of Cr+3 in freshwater and 5.0 pg/L of Cr+6 in saltwater and, to wildlife, 10.0 mg of Cr+6 per kilogram of diet (ppm). Tissue levels in excess of 4.0 mg total Cr/kg dry weight should be viewed as presumptive evidence of chromium contamination, although the significance of tissue chromium residues is unclear. Some of these findings are in sharp contrast to chromium criteria proposed by regulatory agencies. 

Franson, J.C. 1996. Interpretation of tissue lead residues in birds other than waterfowl. Pages 265-280 in W.N. Beyer, G.H. Heinz, and A.W. Redmon-Norwood (eds.). Environmental Contaminants in Wildlife Interpreting Tissue Concentrations. CRC Press, Boca Raton, FL. 

Spalding, M.G., C.K. Steible, S.F. Sundlof, and D.J. Forrester. 1997. Metal and organochlorine contaminants in tissues of nestling wading birds (Ciconiiformes) from southern Florida. Florida Field Natural. 25 42-50. 

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