Pollution of human food with heavy metals has considered an adverse effects on its health. The objectives of this study are to quantify the heavy metal concentrations in 85crab and 71shrimp samples marketed in Mansoura city, Egypt using an atomic absorption spectrometer. The concentrations of arsenic, mercury,
cadmium and lead in crab samples were 0.396 ± 0.014, 0.560 ± 0.017, 0.077 ± 0.003 and 0.789 ± 0.067μg/g, respectively. the concentrations in prawn samples were 0.386 ± 0.02, 0.397 ± 0.049, 0.151 ± 0.019 and 1.123 ± 0.095μg/g for the same heavy metals, successively. However, the differences in raw and cooked samples were not significant and the cooking method may increase the levels of heavy metals due to cooking losses. The present study showed that different metals were present in the samples at
different levels but the majority of them were within the maximum residual levels prescribed by the Egyptian Standard. In conclusion, the flesh of crab and prawn fish sold in markets of Mansoura city, constitute a potential public health hazard considering lead toxicity and to a less degree for the other heavy metals. Such results could be used as a baseline for the monitoring of the level of metals in marine organisms of future studies.