Bioaccumulation And Trophic Level Migration Behavior Of Organic Ultraviolet Absorbers In Typical Industrial Area

Organic ultraviolet absorbents(UVAs)are widely used in cosmetics,personal care products and industrial products to protect skin and polymer materials from light-induced damages.However,studies have shown that UVAs can pose potential adverse effects on plants,animals and even human.The ecological risks of UVAs have been of increasing concern.UVAs are frequently reported in environmental matrices and organisms.However,available information on their occurrence in terrestrial organisms is still extremely insufficient,little is known about the transfer of these chemicals in terrestrial food web.Therefore,the investigation on the UVAs bioaccumulation in terrestrial organisms and their trophic transfer in typical terrestrial food chains are important for better understanding the environmental biogeochemical behavior of UVAs,and provide scientific basis for risk assessment and management of these chemicals.A typical industrial area was selected in this study.Based on the characteristics of local environments and the distribution of plants,the rhizosphere soil,root,stem and leaf of reed,canna,beggartick,South American climber and morning glory,were collected;meanwhile,cabbage butterfly,dragonfly,grasshopper,earthworm,snail,and free-range domestic chicken and pigeons were collected according to the predation characteristics of these animals.The UVAs in plants and animal tissues were analyzed by gas chromatography-mass spectrometry;and the trophic levels of organisms were determined by stable isotopes.The accumulation and transfer of UVAs in terrestrial plants were investigated;the occurrence and bioaccumulation of UVAs in terrestrial animals were studied;and the trophic transfer of UVAs in terrestrial food chains and food webs was investigated.The results were obtained as follows:(1)The total concentrations of UVAs(∑11UVAs)in whole plants were 12.0-242 ng/g dw(median 52.0 ng/g dw).Benzophenone(BP)was the predominant.The ∑11UVAs concentrations in plant tissues decreased as roots>leaves>stems.The concentration of ∑11UVAs in rhizosphere soil was 2.48-13.9 ng/g dw(median 5.44 ng/g dw).The root concentration factors(RCFs)of UVAs were greater than 1,indicating that soil UVAs could be absorbed and stored in plant roots.The tranlocation factors(TFs)showed that most UVAs could be transferred in plants and accumulated in leaves.UVAs had stronger transfer and accumulation than other organic chemicals in soil-plant systems,therefore might have easier access to terrestrial food webs and pose ecological risks to terrestrial organisms.(2)The ∑11UVAs concentrations in invertebrates were 7.51-180 ng/g dw,with a median of 81.3 ng/g dw.Homosalate(HMS),BP,OC and BP-3 were the dominant pollutants.The ∑11UVAs concentrations in muscles of domestic chicken and pigeons ranged from 17.3 to 89.5 ng/g dw(median 53.2 ng/g dw).4-MBC was the predominat chemical.The occurrence of UVAs in these animals were species-specific.The UVAs concentration in tissues decreased as brain>heart>liver>kidney>intestine>stomach>muscle>blood.UVAs excluding EHS and UV-329 could be preferentially accumulated in intestine,liver and kidney,and achieved the dynamic balance.BP,EHS and HMS were preferentially accumulated in heart,brain and liver through blood perfusion.(3)HMS,4-MBC,2-ethylhexyl salicylate(EHS)and 2-(2’-hydroxy3’,5’-di-tert-butylphenyl)benzotriazole(UV-320)in the food chain of grain feed and Qingyuan Partridge chicken showed biomagnification.EHS,BP3 and 4-MBC biomagnified from grain feed to Yao chicken.In the food chain of grain feed and King pigeons,UVAs excluding BP,OC and octyl p-dimethylaminobenzoate(OD-PABA)biomagnified.In the food web of reeds,locusts and curly eyed butterflies,BP,OD-PABA and EHMC showed trophic magnification.HMS,OD-PABA,EHMC,UV-320 and OC biomagnified in the food web of herbs,cabbage butterfly,agate snails and dragonflies,while 4-MBC showed trophic dilution.The main conclusions in this study were drawn as:(1)Soil UVAs could be accumulated by plants,and could enter terrestrial food webs through plants,therefore might pose potential ecological risks on organisms;(2)UVAs were prevalent in terrestrial animals,and showed species and tissue specific distribution;(3)UVAs with logKow>5,or 3<logKow<5 and logKoa≥10 had biomagnification potential in terrestrial food webs,the ecological risks of them should be of concern.Due to the complexity of UVAs distribution in animals and their trophic transfer,the investigation on the occurrence and transfer of UVAs in terrestrial food chains is still warranted.