TY - JOUR
T1 - Oxidation mechanism and overall removal rates of endocrine disrupting chemicals by aquatic plants
AU - Reis, A. R.
AU - Tabei, K.
AU - Sakakibara, Y.
N1 - Funding Information:
This study was supported in part by Grant-in-Aid for challenging Exploratory Research (# 23656334 ), the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan ; and by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA) through Science and Technology Research Partnership for Sustainable Development (SATREPS).
PY - 2014/1/30
Y1 - 2014/1/30
N2 - The purpose of this study was to evaluate experimentally and theoretically the oxidation mechanisms and overall removal rates of phenolic endocrine disrupting chemicals (EDCs) by aquatic plants. EDCs used in this study were bisphenol-A (BPA), 2,4-dichlorophenol (2,4-DCP), 4-tert-octylphenol (4-t-OP), and pentachlorophenol (PCP). Referring to reported detection levels in aquatic environments and contaminated sites, the feed concentration of each EDC was set from 1 to 100. μg/L. Experimental results showed that, except for PCP, phenolic EDCs were stably and concurrently removed by different types of aquatic plants over 70 days in long-term continuous treatments. Primal enzymes responsible for oxidation of BPA, 2,4-DCP, and 4-t-OP were peroxidases (POs). Moreover, enzymatic removal rates of BPA, 2,4-DCP, and 4-t-OP by POs were more than 2 orders of magnitude larger than those by aquatic plants. Assuming that overall removal rates of EDCs are controlled by mass transfer rates onto liquid films on the surface of aquatic plants, an electrochemical method based on the limiting current theory was developed to measure the mass transfer rates of EDCs. Because of extremely large removal rates of EDCs by POs, observed removal rates by aquatic plants were in reasonably good agreement with calculated results by a mathematical model developed based on an assumption that mass transfer limitation is a rate-limiting step.
AB - The purpose of this study was to evaluate experimentally and theoretically the oxidation mechanisms and overall removal rates of phenolic endocrine disrupting chemicals (EDCs) by aquatic plants. EDCs used in this study were bisphenol-A (BPA), 2,4-dichlorophenol (2,4-DCP), 4-tert-octylphenol (4-t-OP), and pentachlorophenol (PCP). Referring to reported detection levels in aquatic environments and contaminated sites, the feed concentration of each EDC was set from 1 to 100. μg/L. Experimental results showed that, except for PCP, phenolic EDCs were stably and concurrently removed by different types of aquatic plants over 70 days in long-term continuous treatments. Primal enzymes responsible for oxidation of BPA, 2,4-DCP, and 4-t-OP were peroxidases (POs). Moreover, enzymatic removal rates of BPA, 2,4-DCP, and 4-t-OP by POs were more than 2 orders of magnitude larger than those by aquatic plants. Assuming that overall removal rates of EDCs are controlled by mass transfer rates onto liquid films on the surface of aquatic plants, an electrochemical method based on the limiting current theory was developed to measure the mass transfer rates of EDCs. Because of extremely large removal rates of EDCs by POs, observed removal rates by aquatic plants were in reasonably good agreement with calculated results by a mathematical model developed based on an assumption that mass transfer limitation is a rate-limiting step.
KW - Biological Fenton reaction
KW - Endocrine disrupting chemicals
KW - Hydrogen peroxide
KW - Peroxidase
KW - Phytoremediation
UR - http://www.scopus.com/inward/record.url?scp=84890290826&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84890290826&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2013.11.042
DO - 10.1016/j.jhazmat.2013.11.042
M3 - Article
C2 - 24333944
AN - SCOPUS:84890290826
SN - 0304-3894
VL - 265
SP - 79
EP - 88
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
ER -