SOLID SAMPLING ZAAS DETERMINATION OF ENDOGENOUS PB CONTAMINATION IN MUSCLE-TISSUE CAUSED BY CALCIFICATION

Focal endogenous Pb contamination in bovine muscle tissue can be cause d by Cysticercus bovis (C. bovis), the larval stage of Taenia saginata . 79 samples of cysts and the respective muscle tissues were analyzed by means of solid sampling Zeeman atomic absorption spectrometry (SS-Z AAS). In calcified cysts of C. bovis, the Pb content was up to 1864 ti mes higher than in the directly surrounding muscle tissue. The maximum Pb content of the cysts was 3.0 mg/kg, that of the muscle tissue 0.02 mg/kg. There is a significant positive correlation between the stage of calcification and the Pb content in the cysts (Spearman rank correl ation: r = 0.869, P less-than-or-equal-to 0.01). Compared to the surro unding muscle tissue, even in non-calcified early stages of the cystic eri, there is a distinctly elevated Pb content. Non-focal endogenous P b contamination in muscle tissue can be caused by calcification of the tissue itself or by calcification of its blood vessels. In the latter case the difference in the Pb content of muscle tissue (myocardium) a nd that of the regions which are prone to calcification (endocardium, endocardial platelets) proved to be highly significant with a ratio of up to < 50. SS-ZAAS proved to be well suited for the determination of Pb in endogenously contaminated muscle tissue where sample decomposit ion methods may lead to incorrect results due to larger sample sizes a nd sample homogenization.