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With the rapid progress of science and technology and the rapid development of society, heavy metal pollution to the marine environment, especially the coastal farming causing serious environmental hazards, and has attracted much attention and become environmental science, biology, one of the hot research issues. Heavy metals in seawater transfer or accumulation through the food chain to fish, especially shellfish products, directly or indirectly threaten human health. Thus, the study of heavy metals in microalgae - shellfish food chain transfer, transmission, has important theoretical and practical significance. In this paper, copper, lead, cadmium for the study, study of heavy metals in Chlorella - philippinarum accumulate in the food chain and delivery, main contents and conclusions are as follows: 1. Philippine clam (Ruditapes philippinarum) enriched seawater Heavy metals research. In a typical economic Jiaozhou Bay shellfish - philippinarum as the research object, simulated philippinarum heavy metals in seawater copper, lead, cadmium enrichment. Hydrostatic method using semi-enrichment experiments salinity of 28.5-29.0 ‰, pH of 8.1-8.3, water copper, lead and cadmium concentrations were 10μg / L, 50μg / L and 100μg / L, Philippines clamshells length of 3.0-3.6 cm, weight 6.0-7.8 g. At 1 d, 3 d, 5 d, 10 d, 15 d, 20 d, 25 d, 30 d Remove some shellfish with Microwave Digestion - Atomic Absorption Spectrometry heavy metal content. Clams in seawater by the Philippine copper, lead and cadmium three kinds of heavy metal enrichment experiment results can be seen philippinarum different concentrations Cu, Pb, Cd enrichment factor BCF varied from :105-268, 185 -690 and 26-85 on the three kinds of heavy metal enrichment capabilities were Pb gt; Cu gt; Cd; enrichment of the same metal, the higher the concentration of heavy metals in water, shellfish enrichment of heavy metals is also higher ; For the enrichment factor, along with the concentration of heavy metal ions in seawater increases reduced. (2) heavy metals on Chlorella (Chlorella) coercive its role in the enrichment of chlorella. At a temperature of 20 ± 1 ℃, salinity 28.5-29.0 ‰, pH is 8.07-8.20, light intensity of 4000 lx, light-dark cycle of L / D = 12/12, using the f / 2 medium to small ball algae were cultured. In Cu 2 , Pb 2 , and Cd 2 concentration of 10μg / L, 50μg / L and 100μg / L solution for pellets algae in heavy metal toxicity and accumulation of stress experiments. The results show, Cu 2 , Pb 2 and Cd 2 the higher the concentration on the growth inhibitory effect is stronger. Chlorella of three heavy metal ions significantly different tolerance, toxicity of heavy metals on the size of chlorella Cd 2 gt; Pb 2 gt; Cu 2 . Equilibrium, the Chlorella Cu 2 , Pb 2 and Cd 2 enrichment capacity Cd 2 gt; Pb 2 gt; Cu 2 , for different concentrations of Cu 2 , Pb 2 and Cd 2 enrichment coefficients were 1626-3161,3198-7799 and 9313-5438, with the waters of the Cu 2 , Pb 2 , Cd < sup> 2 concentration increases, Chlorella Cu 2 , Pb 2 , Cd 2 concentration increases, BCF BCF showed decreasing trend. 3 philippinarum through ingestion of chlorella enrichment of heavy metals. Under controlled conditions to simulate the heavy metals copper, lead and cadmium in Chlorella - Philippine clam food chain accumulation and transfer, determination of heavy metals in the food chain transfer coefficient BCF BCF and BMF. Heavy metals in Chlorella → philippinarum along the transfer process, the content of heavy metals in clams increases over time increased significantly. At equilibrium, the Philippines clams on Chlorella Cu, Pb, Cd enrichment factor BCF 364-821,1089-936 and 245-736, respectively, higher than measured directly from seawater enrichment factor, and its size order of Pb gt; Cu gt; Cd. Cu, Pb, Cd transfer coefficient BMF values ??were less than 1, indicating that three kinds of heavy metals in Chlorella - philippinarum food chain biomagnification no apparent effect, the size of the transfer coefficient BMF Pb gt; Cu gt; Cd. This study will research the ecotoxicology of heavy metals on shellfish lay the theoretical foundation for the development of toxic and hazardous substances in aquatic limited standards provide a scientific basis.
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