Behavior of @entity2887 and XXXX during mechanical, chemical, and active sludge treatment of sewage water and digestion of sludge.

@entity4258 @entity11682 @entity2177 @entity2887 @entity207 @entity800 @entity206
The behavior and fate of three @entity2887 ( @entity4258 , @entity800 , and @entity2177 ), one @entity11682 ( @entity207 ), and @entity206 were investigated at a sewage treatment plant in Ume  , Sweden, in 2004. This plant uses conventional mechanical, chemical, and activated sludge methods to treat the sewage water and digest the sludge; the dewatered digested sludge is pelleted (dry weight > 90% of total weight). Raw sewage water and particles as well as effluents and sludge from specific treatment areas within the plant were sampled. In addition to quantifying the antibiotics within the plant, we characterized the sample matrixes to facilitate evaluation of the results. Of the five substances examined, only @entity4258 , @entity2177 , and @entity206 were present in concentrations higher than their limits of quantification. @entity4258 and @entity2177 sorbed to sludge in a manner that was independent of changes in pH during sewage treatment, and more than 70% of the total amount of these compounds passing through the plant was ultimately found in the digested sludge. The results suggest that @entity2887 undergo thermal degradation during pelleting, but more studies are needed to confirm this. @entity206 was found in the final effluent at approximately the same concentration and mass flow as in the raw sewage, and could not be quantified in any solid sample. Predicted environmental concentrations, based on consumption data for Ume   municipality, correlated well with the results obtained, especially when the predicted concentrations were corrected to account for the amount of each active substance excreted in urine. The results obtained were compared to those of previous studies of these three substances' behavior and fate and were found to be similar, although some of the other plants studied employed the various treatment steps in different orders.
