Enrichment Characteristics And Exposure Risk Assessment Of PBDEs And HBCDs In Edible Aquatic Products Of Guangzhou Residents

Polybrominated diphenyl ethers（PBDEs）and hexabromocyclododecane（HBCDs）as the world’s two largest brominated flame retardants,have the characteristics of persistent organic pollutants（POPs）such as long-lasting environment,long-distance transmission,bioconcentration and toxicology.Two kinds of pollutants can exist in various environmental media and be exposed to the human body through food intake.Aquatic products are the main route through which two pollutants are exposed to food.Accordingly,studying the enrichment characteristics of PBDEs and HBCDs in aquatic products is of great significance for food safety evaluation.In this work,we firstly analyzed the dietary questionnaire survey of aquatic products consumed by Guangzhou residents,and obtained the average daily intake of aquatic products from Guangzhou residents.Secondly,the concentration distribution and pollution characteristics of 8 kinds of PBDEs homologs and HBCDs,319 samples in total,for 7 aquatic products commercially available in Guangzhou were studied.Finally,the daily intake of aquatic products in the questionnaire survey and the concentration characteristics of PBDEs and HBCDs in aquatic products were used to calculate the daily exposure and non-carcinogenic hazard coefficients of PBDEs and HBCDs in aquatic products in order to evaluate the health risks of PBDEs and HBCDs in aquatic products.The findings are as follows:（1）The average daily intake of aquatic products in Guangzhou residents was58.28 g,which satisfies with the recommended average daily intake of aquatic products in a balanced diet pagoda for Chinese residents of 40⁷5 g.It is at a medium level in domestic and foreign research.The average daily intakes of freshwater fish,marine cultured fish,marine fish,shrimp,crab and shellfish were 41.56 g,10.76 g,9.37 g,15.81 g,14.96 g and 26.38 g,respectively.The male’s intake is higher than female’s and the highest intake in the 41–50 age group,while the highest intake is the Nansha District among the 11 administrative regions.The species with the highest consumption among the 7 aquatic products are grass carp,sea bass,band fish,macrobrachium rosenbergii,river crab and scallop.The main edible part is the flesh of fish,the intake frequency is 1–5 times in one month,and the vegetable market is the main access.The aquatic products consumption of Guangzhou residents is mainly affected by the administrative region and monthly income.（2）The concentrations of PBDEs and HBCDs in the edible aquatic products of Guangzhou residents were 1.92 to 91.11 ng/g lw and 0.58 to 58.83 ng/g lw,respectively.The concentration of PBDEs is higher than HBCDs.Whatever,the PBDEs and HBCDs in the edible aquatic products of Guangzhou residents were at moderate pollution levels compared with different countries and regions.Among the eight PBDEs homologs,BDE–209,BDE–99 and BDE–154 are the main homologs,and the major isomer of HBCDs isα–HBCD.The concentrations of PBDEs and HBCDs are varied with administrative regions and aquatic products,which may due to the difference of age,size,diet,fat content,nutritional level and living habits of fish,as well as the fish’s living environment infected by the human characteristics and the pollution levels in different administrative regions.Especially,the pollution sources of PBDEs can be traced to the widespread use of decabromodiphenyl ether and octabromodiphenyl ether.（3）The daily exposure of PBDEs and HBCDs in edible aquatic products of Guangzhou residents was(15.84 ng/kg bw·d^–1 and 1.34 ng/kg bw·d^–1).The aquatic products with the highest daily exposure are freshwater fish(19.67 ng/kg bw·d^–1 and1.66 ng/kg bw·d^–1).The males between 41–50 years old have the highest daily exposure(11.30 ng/kg bw·d^–1 and 0.96 ng/kg bw·d^–1).Nansha is the highest daily intake district(30.74 ng/kg bw·d^–1)and 2.60 ng/kg bw·d^–1).In brief,when compared with other countries and regions,the daily exposure of PBDEs and HBCDs in edible aquatic products of Guangzhou residents is at a medium level.The non-carcinogenic risk hazard coefficients of the eight PBDEs homologues and HBCDs are far below 1,indicating that the non-carcinogenic risks of PBDEs and HBCDs in aquatic products consumed by Guangzhou residents are small or negligible.The ILCR of PBDEs is much lower than10^–6,indicating that PBDEs in Guangzhou’s edible aquatic products have no significant carcinogenic risk.The maximum allowable intake of edible aquatic products for Guangzhou residents is 177.89 g/d,and the allowable intake is 24 times per month.