TY - JOUR
T1 - Oxidation of the cyanobacterial hepatotoxin microcystin-LR by chlorine dioxide
T2 - Reaction kinetics, characterization, and toxicity of reaction products
AU - Kull, Tomas P.J.
AU - Backlund, Peter H.
AU - Karlsson, Krister M.
AU - Meriluoto, Jussi A.O.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2004
Y1 - 2004
N2 - Cyanobacteria are known producers of cytotoxins, hepatotoxins, and neurotoxins. The main toxins are microcystins, cyclic heptapeptide hepatotoxins, produced by strains of several cyanobacterial genera frequently found in eutrophied freshwaters. Due to the acute and chronic toxicity of microcystins, successful removal of these toxins in drinking water treatment processes is of increasing concern. In the present work the kinetics of microcystin-LR (MC-LR) oxidation by chlorine dioxide (ClO2) was studied with UV-spectrometry and high performance liquid chromatography (HPLC). Characterization of reaction products was performed with mass spectrometric (MS) analysis, while the toxicity of reaction products was tested with a protein phosphatase inhibition assay (PPIA). The main reaction products formed, dihydroxy isomers of MC-LR as identified by MS, were nontoxic according to the PPIA. The overall rate constant k for the reaction between MC-LR and ClO2 at 293 K and pH 5.65 was modest, k = 1.24 M-1 s-1, suggesting that ClO2 is not a suitable oxidant for the degradation of microcystins in drinking water treatment processes.
AB - Cyanobacteria are known producers of cytotoxins, hepatotoxins, and neurotoxins. The main toxins are microcystins, cyclic heptapeptide hepatotoxins, produced by strains of several cyanobacterial genera frequently found in eutrophied freshwaters. Due to the acute and chronic toxicity of microcystins, successful removal of these toxins in drinking water treatment processes is of increasing concern. In the present work the kinetics of microcystin-LR (MC-LR) oxidation by chlorine dioxide (ClO2) was studied with UV-spectrometry and high performance liquid chromatography (HPLC). Characterization of reaction products was performed with mass spectrometric (MS) analysis, while the toxicity of reaction products was tested with a protein phosphatase inhibition assay (PPIA). The main reaction products formed, dihydroxy isomers of MC-LR as identified by MS, were nontoxic according to the PPIA. The overall rate constant k for the reaction between MC-LR and ClO2 at 293 K and pH 5.65 was modest, k = 1.24 M-1 s-1, suggesting that ClO2 is not a suitable oxidant for the degradation of microcystins in drinking water treatment processes.
UR - http://www.scopus.com/inward/record.url?scp=8544226269&partnerID=8YFLogxK
U2 - 10.1021/es0400032
DO - 10.1021/es0400032
M3 - Article
C2 - 15573602
AN - SCOPUS:8544226269
SN - 0013-936X
VL - 38
SP - 6025
EP - 6031
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 22
ER -