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1H a/b/c - Pesticides, pharmaceuticals, perfluoroalkylated substances, antibiotics (WEP/14) Understanding the environmental fate of perfluorinated chemicals by CATABOL software. Mekenyan, Ovanes1, Dimitrov, Sabcho1, Kamenska, Verginia1, Lewis, Mark2, Windle, Viletta2, Purdy, Rich3, Walker, John4, 1 Laboratory of Mathematical Chemistry, University “Prof. As. Zlatarov”, Bourgas, Bulgaria, Bulgaria2 Chemical Evaluation Division, Existing Substances Branch , Environment Canada, Quebec, Canada, Canada3 Independent toxicologist, River Falls, USA, USA4 TSCA Interagency Testing Committee, U.S. EPA (7401), Washington, DC, USA ABSTRACT- Perfluorinated chemicals form a special category of organofluorine compounds with particularly useful and unique properties. Their large use over the past decades increased the interest to their environmental fate. Fluorocarbons may have direct environmental impact or indirect trough the products of their decomposition in the environment. It is a common knowledge that biodegradation is restricted within non-perfluorinated part of molecules, however, a number of studies showed that defluorination can readily occur during biotransformation. To evaluate the fate of perfluorinated chemicals in environment a set of principal transformations was developed and implemented in the simulator of microbial degradation using CATABOL software engine. The simulator was used to generate metabolic pathways for about 500 individual perfluorinated chemicals. It was found that although the rate of biodegradation can reach 60% persistent metabolites could be formed in significant quantities. During the microbial degradation a trend was observed according to which perfluorinated chemicals are transformed to more bioaccumulative and more toxic products. Of studied industrial compounds about 17% were predicted to biodegrade to PFOA or PFOS. Key words: organofluorine compounds, perfluorinated chemicals, PFOS, PFOA |
