Characterization of new disinfection by-products of polycyclic musks (AHTN and HHCB) and their metabolites
- The polycyclic musks 6-Acetyl-1,1,2,4,4,7-hexamethyltetraline (AHTN) and 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-ɣ-2-benzopyran (HHCB) are widely used fragrances in cosmetics, products of daily care and cleaning products for households and industry. They are in the focus of interest due to their estrogenic potential. Both compounds can be found at low μg/L concentrations in surface water where they are introduced mainly by sewage treatment plants supplied by municipal wastewater. In order to disinfect wastewater in sewage treatment plants or water in swimming pools, chlorine can be added to water as gas or hypochlorite solution. This disinfectant has a high oxidation potential resulting in the formation of disinfection by-products, the estrogenicity and toxicity of which might differ from their precursor. In this work the behaviour of AHTN and HHCB upon treatment with sodium hypochlorite solution was investigated and chlorinated possible disinfection by-products could beThe polycyclic musks 6-Acetyl-1,1,2,4,4,7-hexamethyltetraline (AHTN) and 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-ɣ-2-benzopyran (HHCB) are widely used fragrances in cosmetics, products of daily care and cleaning products for households and industry. They are in the focus of interest due to their estrogenic potential. Both compounds can be found at low μg/L concentrations in surface water where they are introduced mainly by sewage treatment plants supplied by municipal wastewater. In order to disinfect wastewater in sewage treatment plants or water in swimming pools, chlorine can be added to water as gas or hypochlorite solution. This disinfectant has a high oxidation potential resulting in the formation of disinfection by-products, the estrogenicity and toxicity of which might differ from their precursor. In this work the behaviour of AHTN and HHCB upon treatment with sodium hypochlorite solution was investigated and chlorinated possible disinfection by-products could be identified as well as a carboxylic acids and lactones derived from AHTN and HHCB. The identified species were characterized by GC-MS, LC-MSn and 1H-NMR. The elucidated structures of potential disinfection by-products are verified by X-ray crystallography. Finally the estrogenicity between the parent analytes and generated transformation products were compared. For that task, MCF-7 assay has been chosen for being most relevant to humans. Moreover metabolism studies were carried out using AHTN, HHCB and their disinfection by-products.…