RESUMO
Petroleum hydrocarbon concentrations in seawater, surface sediments and culture shellfish were investigated in shellfish culture area of Sanggou Bay from Jan. to Nov. in 2008. Investigation was conducted on the distribution and variation of petroleum hydrocarbon concentrations in seawater and sediments in the shellfish culture area of Sanggou Bay, as well as on the levels and the differences in petroleum hydrocarbon concentrations among the shellfish species. In addition, the petroleum hydrocarbon pollution status in the three media was evaluated and the effects of accumulated petroleum hydrocarbon in shellfish on the food safety risk were discussed. The results indicated: 1) Petroleum hydrocarbon concentrations in seawater in the shellfish culture area of Sanggou Bay were in the range of 3.61 - 98.21 microg/L; the mean values of petroleum hydrocarbon concentrations in sediments were in the range of 6.75-25.95 mg/kg; petroleum hydrocarbon concentrations in culture shellfish were in the range of 2.14- 42.87 mg/kg; and petroleum hydrocarbon concentrations in shellfish varied largely among different species, with the mean values in the sequence of clam Venerupis variegata > oyster > scallop; 2) Monthly petroleum hydrocarbon concentrations in seawater and surface sediments varied significantly in Sanggou Bay shellfish culture area, with the highest and the lowest values of petroleum hydrocarbon concentrations in seawater that occurred in July and in August, respectively, and with the highest and the lowest values of petroleum hydrocarbon concentrations in surface sediments that occurred in September and in March, respectively; 3) According to the corresponding evaluation criteria, the petroleum hydrocarbon pollution status in surface sediments in Sanggou Bay shellfish culture area was unpolluted but the status in surface seawater was polluted. The culture shellfish was also polluted by petroleum hydrocarbon with different degrees among three species, namely, the pollution degree of clam Venerupis variegata and oyster was more serious than that of scallop Chlamys farreri; 4) The results of linear regression analysis showed that petroleum hydrocarbon concentrations in shellfish had a significantly positive correlation with the concentrations in seawater, while the linear correlation between the concentrations in shellfish and surface sediments was not obvious; and 5) According to the pollution level of petroleum hydrocarbon in shellfish, the food safety risk of three culture shellfishes in Sanggou Bay was relatively low.