The Levels And Congener Profiles Of Polybrominated Diphenyl Ethers In Pine Needles And Children's Plasma From Dalian And Soils From The Modern Yellow River Delta

Polybrominated diphenyl ethers(PBDEs) are additive brominated flame retardants (BFRs) widely used in a variety of consumables.They are ubiquitous in the environment and biota(including people).The impact of PBDEs on the environment and their potential risk for animal and human health is a current concern for the scientific community for several years. Tetra-,penta-,hexa- and hepta-BDEs are listed in the POPs by UNEP in May,2009.The occurrence,level and pattern of PBDEs in the environment and biota appear as an essential issue for furtherly studying their behavior in environment and effects on specific vulnerable population groups and can be the foundation for legislation.In this study,the methods for determination of polybrominated diphenyl ethers(PBDEs) in pine needles,human plasma and soil were developed.Ultrasonic-assisted extraction(UAE), concentrated H₂SO₄ and alumina column for clean-up/fractionati0n were employed to process pine needle and soil samples,and liquid-liquid extraction and clean-up for human plasma. The final extracts were identified and quantified by gas chromatography-negative chemical ionization-mass spectrometry(GC-NCI-MS) with internal standard method in the selective ion monitoring(SIM) mode.The results indicate that the methods have high sensitivity, satisfactory recoveries and good reproducibility.BDE-209 is found to be the dominant congener(82.3%of∑PBDEs) in pine needles,and BDE-47 is the major congener among the lower brominated congeners.For the plasma,the median of PBDE concentrations was 31.61 ng/g lipid weight(lw),which is much higher than those in no-occupational exposure people from GuangZhou,South China and those in human milk of general adults from other cities of China,but are at the moderate levels of those in children around the world.BDE-153 is the predominated congener,followed by BDE-99,47,and 183,which is similar to that in the umbilical cord sera from South China,but different from that from the North America and the Europe.Higher abundant of BDE-183 may suggest more Octa-BDEs used in China.No significant differences are observed between males and females or among different age groups.Breast milk and dust ingestion may be important routes of exposure for children,and children are likely at higher risk of exposure to PBDEs than adults.For the soils from the modem Yellow River Delta,the medians of PBDE concentrations for up-layer,mid-layer and down-layer soils are 103,38 and 8 nk/kg dry weight(dw),respectively.The PBDE levels in present study are lower than that for other regions of China,and at the lower range reported for soils around the world,BDE209 was the predominated congener,contributed～86.1%-99.5%of the total PBDEs,indicating Deca-BDEs is the main source.BDE-99,47,28,100,183,153 and 154 are the major lower brominated congeners.Higher contribution of BDE-28 and 183 are observed,suggesting there are differences in the PBDEs technical mixtures between China and the Euro-American regions.Levels and patterns of PBDEs in the soils from the modern Yellow River Delta have region-specific and soil layer-specific characters.PBDEs levels in soils from the middle area are higher than those of modern course and old course,and there may be local source.PBDEs in up-layer soils have higher levels than the other two layers,indicating the recent inputs of PBDEs to the modern Yellow River Delta over the past years,and hold more complex congeners and more higher-borminated congerners.