Contaminants endogenous

For more comprehensive validation studies, the molecular mass profile of the DNA spike should roughly approximate to the molecular mass range of endogenous contaminant DNA in the crude product. Obviously, the true DNA clearance rate attained by downstream processing procedures (e.g. gel filtration) will depend to some extent on the molecular mass characteristics of the contaminant DNA. 

E2.3.2 Elimination of Proteinaceous and Endogenous Contaminants from Biological Matrices to Minimize Ion Suppression during SPE ... 

The most relevant endogenous contamination arising from the decomposition of formulation constituents is the generation of peroxides in vitamins, amino acids, and lipid emulsions by action of light and air, that is oxygen. 

CPD may not always be simply an endogenous contaminant for example, in smoked products it can be a component of liquid smoke preparations, which contain 200-760 xg/kg of CPD. It may also originate from acid protein hydrolysates used as condiments. High concentrations of 3-CPD (up to 1150 xg/kg) were, for example, found in chicken steaks. CPD can also migrate from some types of... 

Information on the mechanisms of formation of PAHs and derived substances are significant not only in terms of taking measures that minimise possibihties of their penetration into the food chain, but also to reduce endogenous contamination of food in some culinary or technological processes. 

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