The behaviour of N-(phenylsulfonyl)-glycine and phenacetin in a municipal sewage treatment plant - a case study

The behaviour of N-(phenylsulfonyl)-glycine (PSG) and phenacetin (PHE) in a municipal sewage treatment plant near Heidelberg, Germany, was investigate d in the summer of 1997. For that purpose, 10 g of each substance was disso lved and poured simultaneously into the influent. In addition to the spiked compounds, the samples of the influent, the biological stage and the efflu ent were analyzed for N-(phenylsulfonyl)-sarcosine (PSS), N-methyl-N-(pheny lsulfonyl)-amide (MPS), N-methyl-phenacetin. N-methyl-N-(phenylsulfonyl)-ep silon-aminocaproic (PSC) acid and its degradation product N-methy]-N-(pheny lsulfonyl)-gamma-aminobutyric (PSB) acid. Within 24 h PHE could be detected almost quantitatively in the effluent. Since N-methyl-phenacetin could not be found in any of the samples, apparently no methylation of the amino-gro up of PHE took place. The amount of PSG in the effluent was within 24 h 26. 0 g, which is more than two fold higher than added. The decrease of PSG bet ween biological stage and effluent and the increase of PSS within the same time correlate well. Therefore. the formation of PSS by microbial methylati on of PSG in the sewage treatment plant must be assumed. (C) 1999 Elsevier Science Ltd. All rights reserved.