Risk probability due to heavy metals in bivalve from Egyptian Mediterranean coast

Abstract

Abstract An assessment of marine contamination by eight heavy metals (Al, Cd, Co, Cr, Cu, Ni, Pb, and Zn) made along the Egyptian Mediterranean coast. Also, risk probability due to heavy metals contamination in bivalve was investigated. The bivalve samples collected in April 2007 from nine hot spot locations started at El-Mex and ended at Port-Said along Mediterranean coast. The recorded average concentrations of Al, Cd, Co, Cr, Cu, Ni, Pb, and Zn were 137.8 ± 147.4, 0.09 ± 0.04, 2.45 ± 1.29, 8.49 ± 5.19, 3.82 ± 2.21, 10.28 ± 4.09, 0.24 ± 0.15, and 21.87 ± 21.38 μg g−1 dry weight, respectively. In spite of the mollusks species, El-Mex exhibited the highest metal pollution index (MPI), which is expected due to the presence of industrials and agriculture drain near El-Mex location, followed by Port-Said and Abu-Qir stations that suffer from many industrials, marine transportation, fisheries and human activities. Western Harbor and Damietta stations recorded the lowest MPI. Principal component analysis (PCA) and cluster analysis were applied to highlight the relationships between metals. The dendrograms of the cluster analysis confirm the results obtained with PCA. Indeed, depending on the statistical analysis, the studied metals were grouped into two groups, the first group contains Co, Pb, Zn, Cu, Cd and Ni, and the second group includes the remaining two studied metals (Al and Cr). Risk probability study showed that the risk quotients for Cd, Cu, Ni, Pb, and Zn in both the best-case and worst-case scenarios do not cause adverse effect for either low or high consumption groups. Only chromium recorded a risk quotient three times greater than the worst-case scenarios, which may associate health problem for the heavy shellfish consumers groups.