Predicting reductive debromination of polybrominated diphenyl ethers by nanoscale zerovalent iron and its implications for environmental risk assessment.
The reductive debromination of polybrominated diphenyl ethers (PBDEs) by nanoscale zerovalent iron (nZVI) has proven to be a successful remediation approach. This study simulates the congener profiles and overall ecotoxicological impact of PBDE debromination by nZVI. The relationship between the calculated redox potential values and PBDE debromination rates was sufficiently strong to generate a satisfactory predictive capacity, which was further used to develop a quantitative structure-activity relationship (QSAR) model for the determination of the PBDE debromination patterns and dominant pathways. The predicted results of deca-BDE debromination showed that it would completely disappear within 30 days, but its lower brominated products, particularly tri- to penta-homologues, could exist in the environment even after 5 years. Formation and accumulation of more toxic, low brominated congeners through deca-BDE debromination suggest that deca-BDE may pose prolonged environmental risks. Changes in the toxic equivalent (TEQ) values during deca-BDE debromination parallel the occurrence and transformation of specific low brominated congeners with dioxin-like potency.
School of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea.
Eun-Ju
EJ
Kim
School of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea.
Jae-Hwan
JH
Kim
School of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea.
Ji-Hun
JH
Kim
School of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea.
Varima
V
Bokare
School of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea. Electronic address: yschang@postech.ac.kr.
Yoon-Seok
YS
Chang
D004785:Environmental Pollutants / Q000737:chemistry*; D005411:Flame Retardants / Q000032:analysis*; D055768:Halogenated Diphenyl Ethers / Q000032:analysis / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008956:Models, Chemical; D021281:Quantitative Structure-Activity Relationship; D018570:Risk Assessment
D004785:Environmental Pollutants; D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D007501:Iron
Dioxin-like activity; Nanoscale zerovalent iron (nZVI); Polybrominated diphenyl ethers (PBDEs); Quantitative structure–activity relationship (QSAR); Reductive debromination