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Characterization of cylindrospermopsin chlorination
Sylvain Merel1, Michel Clément, Annick Mourot
1Environment and Health Research Laboratory (LERES), French School of Public Health (EHESP), Avenue du Professeur Léon-Bernard-CS 74312, 35043 Rennes Cedex, France.
The Science of the Total Environment
|May 22, 2010
Summary
Chlorination of cylindrospermopsin, a cyanotoxin, rapidly transforms it into by-products. This process significantly reduces the toxicity of drinking water treatment mixtures.
Area of Science:
- Environmental Science
- Water Treatment Chemistry
- Toxicology
Background:
- Cyanobacterial blooms are a growing threat to drinking water safety in temperate regions.
- Cyanotoxins, like cylindrospermopsin, require effective removal during water treatment.
- Chlorination is a common disinfection method, necessitating an understanding of its interaction with cyanotoxins.
Purpose of the Study:
- To investigate the chlorination process of cylindrospermopsin.
- To identify and characterize cylindrospermopsin chlorination by-products.
- To assess the impact of chlorination on the cytotoxicity of cylindrospermopsin.
Main Methods:
- Monitoring of reactants and by-products using UV spectroscopy and Liquid Chromatography-Mass Spectrometry (LC-MS).
- Accurate mass measurement with LTQ-Orbitrap mass spectrometer for by-product identification.
- Cytotoxicity assessment on human intestinal Caco-2 cells measuring mitochondrial and lysosomal activity.
Main Results:
- Cylindrospermopsin rapidly transformed into at least one intermediate by-product.
- Mass spectrometry confirmed near-complete cylindrospermopsin transformation within 5 minutes.
- A new, stable chlorination by-product with the formula C(13)H(18)N(4)O(7)S was identified, alongside previously known compounds.
- Chlorination significantly decreased the overall cytotoxicity of the reaction mixture.
Conclusions:
- Chlorination effectively transforms cylindrospermopsin into various by-products.
- The identified by-products, including a novel compound, are less cytotoxic than the parent toxin.
- Chlorination is a promising method for reducing the health risks associated with cylindrospermopsin in drinking water.
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