Role of polarity fractions of effluent organic matter in binding and toxicity of silver and copper.
This study evaluates the effect of the physicochemical properties of effluent organic matter (EfOM) from industrial and sewage wastewater treatment plants (WWTPs) on the binding and toxicity of Ag and Cu. EfOM was isolated into hydrophobic, transphilic, and hydrophilic fractions depending on its polarity, and was characterized by elemental, specific ultraviolet absorbance, and fluorescence excitation-emission matrix analyses. Our results suggest that the EfOM consists of microbially derived non-humic substances that have lower aromaticity than the Suwannee River natural organic matter (SR-NOM). The Freundlich model was better at explaining the binding of Ag and Cu onto both SR-NOM and EfOM than the Langmuir model. In particular, the hydrophilic fractions of sewage EfOM showed higher binding capacities and affinities for Ag and Cu than the corresponding hydrophobic fractions, resulting in better reduction of the acute toxicity of Ag and Cu towards Daphnia magna. However, in the case of both SR-NOM and industrial EfOM, the hydrophobic fractions were more efficient at reducing metal toxicity. These findings suggest that the EfOM has different physicochemical properties compared with NOM and that the binding and toxicity of heavy metals are largely dependent on the polarity fractions of EfOM.
Division of Environmental Science & Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
Jisu
J
Yoo
Division of Environmental Science & Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
Taeyong
T
Shim
Department of Environment and Energy, Sejong University, Seoul 05006, Republic of Korea.
Jin
J
Hur
Division of Environmental Science & Ecological Engineering, Korea University, Seoul 02841, Republic of Korea. Electronic address: jjung@korea.ac.kr.
Jinho
J
Jung
D000818:Animals; D003300:Copper / Q000737:chemistry / Q000633:toxicity*; D003621:Daphnia / Q000187:drug effects; D057927:Hydrophobic and Hydrophilic Interactions; D012834:Silver / Q000737:chemistry / Q000633:toxicity*; D023382:Toxicity Tests, Acute; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*
D003300:Copper; D012834:Silver; D062065:Wastewater; D014874:Water Pollutants, Chemical
Acute toxicity; Bioavailability; Effluent; Heavy metal; Organic matter