Bioaccumulation Of Endocrine Disrupting Chemicals In Freshwater Organisms From The Pearl River,South China

Endocrine disrupting chemicals(EDCs)are natural,exogenous and synthetic chemicals that block or mimic to natural hormones,they can antagonize the action or modify the synthesis,release,transport,bindingand metabolism of the endogenous hormones in the body.Many studies have shown that EDCs have been linked to early puberty,birth deformities,impaired immune function,different types of cancer,and other diseases.Currently,EDCs have been detected in environmental media all over the world,namely drinking water,house dust,sediment and soil.However,systematic studies on the bioaccumulation of EDCs and mechanisms are limited.In this study,10 typical representatives of EDCs,including Methylparaben(MP),Ethylparaben(EP),Propylparaben(PP),Butylparaben(BP),2-Phenylphenol(PHP),Bisphenol A(BPA),Triclosan(TCS),Triclocarban(TCC),Nonchlorinated carbanilide(NCC),and Dicyclohexylcarbodiimide(DCC),were collectively selected as the target compounds.This study summaried of the concentration,the tissue distribution,the bioaccumulation and the biomagnification of EDCs,and assess factor affecting the bioaccumulation potentials.The main results of this study listed as follows:(1)This study presented an analytical method for simultaneous determination of EDCs in biolta using ultra-high performance liquid chromatography–tandem mass spectrometry(UHPLC–MS/MS).The pretreatment procedures involved vortex mixing and ultrasonic assisted extraction followed by purification with gel permeation chromatography and silica gel column fractionation.Recoveries were predominately 65.2%-118.0%.The method quantification limits were 0.1-9.7 ng/g dry weight(dw).(2)Nine EDCs were detected in the wild freshwater organisms from the Pearl River except NCC.There was a great interspecific difference in the bioaccumulation of EDCs in wild freshwater organisms from the Pearl River.TCC was detected only in the ridgetail white prawn;the concentration ratio of TCC to EDCs was 56%;the detection rate of TCC was 100%;PHP and MP were the minor components in the ridgetail white prawn.The detection rate of BPA was 96.67%;TCS and MP were the minor components in the fish.The concentration of MP in carnivorous fish was significantly higher than other fish,which was 402.52 ng/g lw.The concentration of TCS and BPA in carnivorous fish was significantly lower than other fish.(3)There was a great difference in the distribution and bioaccumulation among different tissues of wild freshwater fish from the Pearl River.The distribution and logBAF of MP,TCS and BPA studied in the tissues of fish were in accordance with the order: liver> belly> filet.The results indicated the accumulation ability of different tissues: liver> belly> filet.(4)The distribution n of EDCs among different species of wild freshwater fish from the Pearl River was closely related to their living environment.In general,the concentrations of EDCs in the fish from Guangzhou was higher than other sites.The bioaccumulation of MP,TCS and BPA showed significant differences in seasons.For example,the concentration of MP,TCS and BPA in the filet of Guangdong black bream in different seasons complied with the following order: rainy season> dry season.The bioaccumulation of EDCs showed significant differences in growth stage.The concentration of MP in the filet of fish had tendency of increasing with length and weight increased.The concentration of TCS in the filet of fish had tendency of reducing with length and weight increased.The bioaccumulation of EDCs showed significant differences in sex.The concentration of MP in the filet of redbelly tilapia in different sex complied with the following order: female> male.The concentration of TCS in the filet of prussian carp and Guangdong black bream in different sex complied with the following order: female> male.The concentration of BPA in the filet of barbel chub and redbelly tilapia in different sex complied with the following order: female> male.(5)The transfer of EDCs along the food chain in the Pearl River showed obvious biomagnification and maternal transfer.The TMF of TCS was 1.62,which may produced biomagnification with the delivery of the food chain(net).The TMF of BPA was 0.92,while the TMF of MP was 0.33,which may produced biological dilution with the delivery of the food chain(net).MP,TCS and BPA were easy to transfer from the mother to the eggs in fish.