Musk xylene and musk ketone amino metabolites in the aquatic environment

Abstract

The monoamino metabolites of the nitro musk fragrances musk xylene (MX) and musk ketone (MK) were analysed simultaneously with their parent compounds by GC/ECD, GC/PND and GC/EI/MS in the various compartments of the aquatic environment. In this review the data of the metabolites 4-NH 2–MX, 2-NH 2–MX, and 2-NH 2–MK in five river water and seven sewage samples, six sediment samples and in a total of 33 biota samples are summarized and discussed. In the effluents of two municipal sewage plants low nitro musk concentrations and comparatively high levels of the amino metabolites (maximum concentrations: 34 ng 4-NH 2–MX/L, 250 ng 2-NH 2–MK/L) were analysed indicating that besides adsorption to the sludge the metabolization pathway plays an important role in the sewage plant. In water samples from the river Elbe the transformation products were the dominant compounds as well. In general, in water samples the concentrations of 2-NH 2–MK exceeded those of the main MX metabolite 4-NH 2–MX significantly. In biota samples 4-NH 2–MX seems to be the main metabolite, very often its contents were higher than those of the parent compound. Maximum concentrations of 4-NH 2–MX were found in tenches from a sewage pond (3600 μg/kg lipid), a species dependent bioaccumulation was discussed. The bioconcentration of 2-NH 2–MK in biota samples is relatively low. There are only few toxicological studies on the mixed amino nitroaromatics, whose data indicate the relevance of the monoamino metabolites in environmental analysis and toxicology and the urgent need of further investigations.