Distribution of Pb and Cd in the liver of the mallard — direct determination by means of solid sampling ZAAS

The distribution of Pb and Cd in livers of the mallard (Anas platyrhynchos) was analysed by means of solid sampling AAS with direct ZEEMAN effect background correction (SS-ZAAS). In the case of Pb the analyses of variance indicated a negligibly low influence of heterogeneity on the final result. In a range of 0.03–1.2 ng/mg fresh matter (sample sizes: 0.4–15.7 mg) the variance due to heterogeneity proved to be distinctly lower than the residual experimental error. The anatomical location of the sampling site remained without significant influence. In the case of Cd (0.09–2.4 ng/mg, sample sizes: 0.05–14.1 mg), however, an increased degree of heterogeneity was observed in 50% of the livers. Here, the influence of heterogeneity can be effectively reduced by means of an adequate sampling scheme, which was shown by a comparison of methods including SS-ZAAS and a sample decomposition method.