Bioaccumulation Of Organic Ultraviolet Absorbents In Freshwater Aquatic Organisms From The Pearl River Basin

Ultraviolet filters(UVFs)are widely used as additives in personal care products to protect human skin and hair from damage caused by UV radiation,and UV stabilizers(UVSs)are added to a variety of industrial products for delaying degradation and aging.After application,UV absorbers(UVAs)will enter the environment through leaching,evaporation and other ways..At present,organic UVAs have been detected in atmosphere,water,sediments,organisms and other environmental matrices.In order to comprehensively and objectively assess the biological and ecological hazards of UVAs,,distribution of UVAs in biological tissues and the factors that affect the enrichment of UVAs in organisms are need to be revealed.The Pearl River Basin is ideal for studying the enrichment of organic UVAs in organisms,due to the long-term sunshine,strong ultraviolet radiation,high population density,,prosperous economy and developed industry.In this study,we chose of 13 UVAs belonging to 7 categories,commonly used in China,as the target compounds,including 3-(4-methylbenzylidene)camphor(4-MBC),2-ethylhexyl-4-(dimethylamino)benzoate(ODPABA),2-hydroxy-4-methoxy benzophenone(BP-3),2-hydroxy-4-octyloxybenzophenone(UV-531),avobenzone(AVO),2-ethylhexyl-4-methoxy cinnamate(EHMC),2-ethylhexyl-2-cyano-3,3-diphenylacrylate(OCR),2-(2-hydroxy-5-methylphenyl)benzotriazole(UV-P),2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol(UV-234),2-(3-tert-butyl-2-hydroxy-5-methyl phenyl)-5-chloro-2H-benzotriazole(UV-326),2-(2'-hydroxy-3',5'-di-tert-butylphen yl)-5-chloro-2H-benzotriazole(UV-327),2-(2-hydroxy-3,5-di-tert-pentylphenyl)-2Hbenzotriazole(UV-328)and 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethyl butyl)phenol(UV-329).The main objective of this study were 1)to study the distribution of theUVAs in typical aquatic organisms in the Pearl River,and 2)to explore their enrichment and amplification in aquatic organisms and the relevant influencing factors.The main results of this study are listed as follows.(1)The total concentrations of UVAs in the filet of all aquatic organisms is from 141.31 to 1650.79 ng/ g lipid weight(lw).The mainly detected UVAs were BP-3,UV � 531,UV-P and UV-234,and UV-531 presneted the highestof 401.48 ng/g lw.The concentration range of UVAs in osteichthyes(305.99-793.62 ng/g lw)was higher than that in crustaceans(154.81-277.35 ng/g lw).Concentrations in the carnivorous fishes(600.39 ng/g lw,mean)were higher than the omnivorous(515.06 ng/g lw mean),the herbivorous(363.33 ng/g lw,mean),the filter-feeding(340.81 ng/g lw,mean).EHMC mainly existed in the muscles of carnivorous fishes,and shown obvious enrichment in shrimps.The concentrations of UVAs measured during the dry season(October to March of next year)were higher than those in the rainy season.Habitat habits of organisms did not lead to significant concentration differences of the UVAs,probably because of that the depth of water system of the Pearl River is not enough to result in significant differences of habitat habits.(2)UVAs presented in biological tissues at different concentration levels,mainly following the order as follows: liver > belly > filet.This might be related to the lipophilicity of UVAs.In the muscle tissues of red belly tilapia,the concentrations of total UVAs(?UVAs)increased first and then decreased with the increase of body length,and those in the muscle tissues did not show significant gender differences.(3)UVAs widely distributed in eggs,and the concentration of EHMC in ridge tail white prawns' eggs was significantly higher than those in the tissues of male muscle and maternal muscle.This suggested that UVAs might migrate to the offspring of crustaceans.(4)The logarithm value of the bioaccumulation factor(Log BAF)of UVAs was greater than 3.3,indicating that UVAs were capable of bioaccumulation.despite of that the LogBAF and LogKow values of UVAs did not show significant correlations(p>0.05),but a insignificantly positive correlation(slope = 0.24,r=0.51).The Biotasediment Accumulation Factor(BASF)values of UVAs ranged from 0 to 17.9.UVA-531 had the highest BSAF value exceeding 1,showing that it is more likely to accumulate in the organisms than in the sediment.(5)The trophic biomagnification factors(TMFs)of UVAs were 0.76-1.79.While the TMFs of OCR,UV-531 and UV-234 are higher than 1,indicating that they could be biomagnified via the food chains.