|
1M - Chiral pollutants (MOP/59) Polycyclic musk fragrances in sewage plants and surface waters - Chiral indications for biodegradation -. Bester, Kai1, Spiteller, Michael 1, 1 Institute of Environmental Research, Dortmund, NRW, Germany ABSTRACT- Polycyclic musk fragrances in sewage plants and surface waters - Chiral indications for biodegradation Bester K., Spiteller, M. Institute for Environmental Research, Dortmund, Germany k.bester@INFU.uni-dortmund.de Polycyclic musks such as HHCB (galaxolide) or AHTN (tonalide) which are used as fragrances in a multitude of consumer products, exhibit chiral centers. As enzymatic degradation often is enantioselective while all other processes (photooxydation, hydrolysis etc.) are not, it is possible to discriminate physical and biochemical degradation processes, e.g., in sewage plants by means of chiral gas chromatography. In this study the total balance of HHCB and AHTN on a sewage plant is described including influent, effluent and sewage sludge on one plant. The respective metabolite HHCB-lactone is also taken into account. About 55 % of the HHCB leaves the plant without alteration, about 35 % of the HHCB is sorbed to the sludge, and about 10 % of the HHCB is biotransformed to the HHCB-lactone. The enantiomeric ratios of HHCB in the samples from the plant under investigation exhibited significantly alterations compare to standard solutions, thus supporting the results on biodegradation. A comparison of sludges obtained from other plants exhibit higher concentrations in some plants, and interestingly varying enantiomeric ratios of HHCB and AHTN. Thus there is a clear indication that diverse sewage plants with different microbial communities exhibit different degradation capacities for organic microcontaminants. The respective compounds (HHCB and AHTN) as well as the metabolite (HHCB-lactone) are found to be present with elevated levels of rivers. Key words: chiral separation, polycyclic musks, biodegradation, HHCB, AHTN |
