Description:    The impacts of dissolved organic matter (DOM) on the removal of 17β-estradiol (E2) in horseradish peroxidase (HRP)-mediated oxidative coupling systems were investigated in this study. The results showed that the removal rate of E2 and the affinity of HRP to E2 had been significantly decreased in the presence of DOM. Compared with urban sludge DOM (USDOM), river sediment DOM (RSDOM), which features relatively low aromaticity and molecular weight and a large number of O-containing groups, more strongly inhibited the E2–HRP–H 2 O 2 reactions than USDOM. The products were analyzed with electrospray ionization mass spectrometry. The results suggested that the self-coupling of E2 was suppressed in the presence of DOM, likely resulting from cross-coupling between DOM and E2 or self-coupling of DOM in the HRP system. The results are useful in understanding the fate of estrogens in natural systems. Content Type Journal Article Pages 1-10 DOI 10.1007/s11270-012-1359-2 Authors Wei Huang, School of Chemistry and Environment, South China Normal University, Universities Town, Guangzhou, 510006 People’s Republic of China Haiyan Song, School of Chemistry and Environment, South China Normal University, Universities Town, Guangzhou, 510006 People’s Republic of China Hongqin Xie, Dongguan Environmental Monitoring Station, Dongguan, 523009 People’s Republic of China Youyi Yin, School of Chemistry and Environment, South China Normal University, Universities Town, Guangzhou, 510006 People’s Republic of China Erwen Yuan, School of Chemistry and Environment, South China Normal University, Universities Town, Guangzhou, 510006 People’s Republic of China Hong Xiao, School of Chemistry and Environment, South China Normal University, Universities Town, Guangzhou, 510006 People’s Republic of China Jianzhong Wu, School of Chemistry and Environment, South China Normal University, Universities Town, Guangzhou, 510006 People’s Republic of China Guangying Zhou, School of Chemistry and Environment, South China Normal University, Universities Town, Guangzhou, 510006 People’s Republic of China Journal Water, Air, & Soil Pollution Online ISSN 1573-2932 Print ISSN 0049-6979 Journal Volume Volume 224 Journal Issue Volume 224, Number 1