Detection,Analysis,and Evaluation Of Lead And Cadmium In Aquatic Organisms In The Offshore Waters Of Jiao Jiang District Of Taizhou City

Ocean environment is an integral part of the global ecological system,including offshore waters,which is related to human life and activities.The environmental and ecological quality of offshore waters is a prerequisite for ensuring the sustainable development of natural resources.The biological index is particularly important in environment monitoring and quality estimation of water quality in offshore waters.Therefore,it is of special importance to monitor the quality and safety of aquatic organisms offshore.Heavy metals,as the persistent pollutant,have teratogenic,carcinogenic,and deadly harm to the aquatic organisms.They can also pass through the food chain,biomagnify,and even be harm to human health.Therefore,the detection of heavy metal content in aquatic organisms is of great significance.Through the analysis of the detected data,the distribution pattern of different types of heavy metals in aquatic organisms was investigated.It plays an important role in guiding the decision-making and analysis of aquatic organisms detection.Jiaojiang District of Taizhou is located in the southeast coastal areas of China,with a land area of nearly 300 square kilometers,a sea area of 1604 square kilometers,and a coastline of 51.4 kilometers.In previous decades,with the rapid development of the Yangtze river triangle area,the coastal areas of Taizhou were polluted by land-based pollution,mariculture and marine transportation.The pollution in coastal waters is aggravated,especially the emission of heavy metal pollutants.Therefore,it is necessary to carry out the detection and analysis of heavy metal content in aquatic organisms of Jiaojiang offshore area.At the same time,we should pay more attention to content of heavy metals in aquatic organisms.The heavy metals,lead(Pb)and cadmium(Cd),in different kinds of aquatic organisms in different periods captured in the offshore area of Jiaojiang District of Taizhou city were analyzed in the research.The variation of Pd and Cd’s content in aquatic organisms of different types and different years was alos studied.In addition,combined with the water quality background of offshore water in Jiaojiang District of Taizhou City,diet safety of aquatic organisms referring to the relevant national aquatic organisms heavy metal limited standard was assessed.From 2014 to 2016,a total of 186 batches(91 batches of fish,50 batches of crustaceans,27 batches of shellfish and 18 batches of cephalopods)of aquatic organisms were collected.According to standard detection technology(GB 5009.12-2010 and GB 5009.15-2014),detection was based on graphite furnace atomic absorption spectrometry.Finally,the aquatic organisms sample data were analyzed and classified.The software SPSS Statistics 17.0 system was used for statistical analysis.The results showed as follows:1.Through the detection and analysis of different kinds of aquatic organisms,the XMPI index of heavy metals in shellfish products was significantly higher than those of other aquatic organisms,0.2366.While the XMPI indices of heavy metals in fish and crustacean were lower,0.07841 and 0.07251.2.There was no significant difference of Pb content among the 4 different kinds of aquatic organisms,and Pb was found slightly higher than the other 3 kinds of aquatic organisms,0.2361mg/kg.The difference in Cd was significant among the aquatic organisms.Cd was highest in cephalopods and shellfish,0.2891 mg/kg and 0.2371 mg/kg.It can be seen that shellfish is liable to be contaminated by Pb and Cd.Therefore,we should enhance the monitoring of Pb and Cd in shellfish.3.The degrees of exceeding the standard are different in different kinds of aquatic organisms:the highest exceeding standard rate of Pb was in crustaceans,which is 8%;the highest rate of Cd was in cephalopod,which is 5.56%.4.The single factor pollution index method of heavy metals is used to evaluate the pollution.The results showed that the pollution of Pb and Cd in all kinds of aquatic organisms was low.5.Through continuous monitoring of aquatic organisms for three years,the contents of lead and cadmium in the aquatic organisms of Jiaojiang district of Taizhou city showed a downward trend.Lead content decreased rapidly,but the.cadmium content decreased slowly,and the difference is not significant.Therefore,it is suggested that the relevant departments should strengthen the control of cadmium pollution.