Heavy metals and hydrocarbon concentrations in water, sediments and tissue of Cyclope neritea from two sites in Suez Canal, Egypt and histopathological effects

Heavy metals and hydrocarbons are of the most common marine pollutants around the world. the present studyaimed to assess the concentration of petroleum hydrocarbons and heavy metals in tissues of the snail cyclopeneritea, water and sediments from two sites of the study area (temsah lake and suez canal) represent polluted andunpolluted sites respectively. the results showed that, the levels of the heavy metals (pb, cd, co, mg and zn) in thepolluted area have reached harmful limits recorded globally. lead in water, sediment and tissue of the snailreached to 0.95 ppm, 4.54 ppm and 7.93 ppm respectively. cadmium reached 0.31 ppm, 1.15 ppm and 3.08 ppm inthe corresponding samples. cobalt was not detected in water, but it reached 1.42 ppm and 10.36 ppm in thesediment and snails tissue respectively. magnesium in water, sediment and tissue of the snail reached 3.73 ppm,9.44 ppm and12.6 ppm respectively. zinc reached 0.11 ppm, 3.89 ppm and 12.60ppm in the correspondingsamples. meanwhile, hydrocarbons in the polluted area (site1) reached 110.10 ?g/l, 980.15 ?g/g and 228.00 ?g/g inwater sediment and digestive gland tissues of the snails respectively. whereas, hydrocarbons in the unpolluted area(site2) were estimated as 14.20 ?g/l, 55.60 ?g/g and 22.66 ?g/g in water, sediment and tissue of the snails respectively.the combination of histopathological image with monitoring of the metal level in the digestive gland of thepresent snail provides an important tool for early detection of impending environmental problems and potentialpublic health issues. petroleum hydrocarbons are toxic to the marine fauna when present above certain limit inthe marine water. the major detoxification organ in molluscs is the digestive gland, which has been used as abioindicator organ for toxicity assessment. the effect of high crude oil on the digestive gland tubules of exposedsnails when examined microscopically reveals a series of histological changes which indicates that the cellularcompensatory mechanism is activated by hydrocarbons. these changes include vacuolation and presence ofpyknotic nuclei.