| As people’s living standard rising, people’s awareness of quality and safety of aquatic products is becoming more and more high. Improve the quality and safety of aquatic product is of great significance to protect consumer’s health. Heavy metal pollution is one of important pollution to aquatic product. In order to control heavy metal pollution of aquatic products and provide scientific basis for aquaculture, this experiment takes the Procambarus clarkii as the research object, and study the heavy metal pollution condition of Procambarus clarkii and the accumulate and release regularity. The content of this text includes three parts:1. Heavy metals of arsenic, mercury, lead, cadmium in Procambarus clarkii collected from four areas of Huaian were analyzed. The results assessed according to the national standard show that:the four heavy metals in Huaian were detected but not beyond the standard and the Procambarus clarkii is safe to eat. Single-factor contaminant index and Comprehensive pollution index were utilized for assessment. It was found that Pi<1.0and the Procambarus clarkii was not be polluted by arsenic, mercury, lead, cadmium. But more attention should be pay to lead for it’s Pi was between0.7and1.0,in individual samples.2. Kinetic parameters were evaluated for biological accumulation and release of two heavy metals Cd and Cu in gill, hepatopancreas and muscle of Procambarus clarkii in the condition of the laboratory to carry out the experiment in which the lobster were exposed to the water environment with Cd concentration of0.05mg/L,0.10mg/L, and Cu concentration of0.50mg/L,1.0mg/L. Heavy metal uptake rate constant (k1), extracting rate constant (k2), bioconcentration factor (BCF) and biological half-lives (B1/2), equilibrium concentration of heavy metals in vivo CAmax were obtained by non-linear curve fitting. The results showed: Obvious concentration of Cd and Cu was found in Procambarus clarkii and the concentration of heavy metals in lobster gill, hepatopancreas, muscle exhibited an apparent positive correlation to accumulation time as well as the exposure concentration of heavy metals。But the number of the concentration ware different in different tissure.The order of enrichment quantity of Cd:hepatopancreas>gill>muscle; The order of enrichment quantity of Cu:gill>hepatopancreas> muscle. Accoding to the model, the maximal metal contents in gill, hepatopancreas and muscle (CAmax) were positively correlated to the exposure concentration. The bioconcentration factor (BCF) of Cd and Cu in the tissues and organs ranged from2to207and3to226respectively; The biological half-lives of Cd and Cu in the tissues and organs (B1/2) ranged from3to28d and7to36d,which signified that the obsorption and release ware not that different from Cd to Cu.3. Under the conditions of natural environment, the interaction of the two metals (Cu and Cd) was studied in three organs and tissues (gill, hepatopancreas,muscle) of Procambarus clarkii in the process of absorbing accumulating heavy metal, by the exposure method of mixed system and sequential system. The results showed that Cu and Cd in hepatopancreas and gill showed a clear antagonism effect.In the mixed exposure system the concentration of Cu and Cd was restrained with the increasing of the concentration of Cd (or Cu).In the sequential system,the concentration of Cu and Cd of the three tissues was clearly decreased compared with in tne mixed system. in addition in the sequential system the concentration of Cu (or Cd) per-exposed was decreased after the addition of Cd (or Cu). Metabolic rate of Cu (or Cd) of the three tissues were positively related to the exposed concentration of Cd (or Cu). |
PDF Full Text Request