Study Of Bioaccumulation And Biotransformation Of BDE209in Eisenia Fetida And Maize

With the penta-BDEs and octa-BDEs were disabled, the decaBDEs are widely used bymore and more people.The deca-BDEs with high fat content, low volatility characteristics,environmental stability, persistence and bioaccumulation, and its flame retardant propertiessuperior to other flame retardants. Currently decaBDEs are prevalent and use in the world,therefore it become a research hotspot.In order to explore the accumulation and biotransformation of BDE209in soil animaland plant, we selected Eisenia fetida and maize as subjects, Respectively, in14days,28days,42days,56days and70days of the five period of time, study on the accumulation of BDE209in Eisenia fetida of artificial soil, with a series of concentrations of BDE209at50mg/kg,100mg/kg,500mg/kg,1000mg/kg,3000mg/kg;study of accumulation and transformation ofBDE209in root shoot leave of maize in artificial soil in56days; use of environmental soil toresearch accumulation and biotransformation of Eisenia fetida and maize; Calculation ofbioconcentration factors of earthworms and corn for PBDEs, determine the bioavailability ofPBDEs.The results were as follows:(1)The earthworms (Eisenia fetida) have certain biological enrichment of BDE209in soil,accumulation increased with the exposure dose, but with the extension of exposure time firstincreased and then decreased. Accumulation of Eisenia fetida, reached a maximum at fourthweeks,154930ng/g, after the stock began to fall. The Eisenia fetida on the enrichment fatorof BDE209in soil is0.44-1.11.(2)The debrominated reaction of BDE209occurred in Eisenia fetida. It can detected11kinds of PBDE congeners. The mainly products of debromination were BDE207,BDE203,BDE206,BDE208high brominated congeners andBDE47,BDE99, BDE153lower brominatedcongeners. At the same time period, with increasing of exposure dose, the content ofdebromination degradation product of BDE209also increased. While at the same exposuredose, the lower brominated congeners of PBDE are gradually increased and reached amaximum of10weeks, the high brominated congeners reached a maximum of4weeks. Themainly products of debromination was BDE207, The contents of∑PBDE accounted for24.91%~38.28%(3) In the simulation conditions, accumulation of BDE209in maize was root> shoot>leaf, and with the exposure concentration increases, the root bioaccumulation factor significantly larger. when BDE209concentrations in the soil is3000mg/kg, the BAFs of5.296.while the root, shoot leave of maize and soil have occurred debromination metabolismof BDE209, transformation products are mainly BDE207, BDE206, BDE196and BDE85etc.,and BDE206was the largest proportion.(4)The bioaccumulation ability of BDE209of Eisenia fetida in the soil of environment isdifferent form simulated conditions of laboratory, with the extension of exposure time and thecontent of BDE209increased. At the same time, we found that Eisenia fetida couldaccumulated low-brominated congeners form soil.