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 investigated in the summer of 1997. For that purpose, 10 g of each substance was dissolved and poured simultaneously into the influent. In addition to the spiked compounds, the samples of the influent, the biological stage and the effluent were analyzed for N-(phenylsulfonyl)-sarcosine (PSS), N-methyl-N-(phenylsulfonyl)-amide (MPS), N-methyl-phenacetin, N-methyl-N-(phenylsulfonyl)-epsilon-aminocaproic (PSC) acid and its degradation product N-methyl-N-(phenylsulfonyl)-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-group 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 between biological stage and effluent and the increase of PSS within the same time correlate well. Therefore, the formation of PSS by microbial methylation of PSG in the sewage treatment plant must be assumed.     

Accumulation pattern and biotransformation enzyme induction in rainbow trout embryos exposed to sublethal aqueous concentrations of 3,3',4,4'-tetrachlorobiphenyl

Accumulation pattern of 3,3',4,4'-tetrachlorobiphenyl (PCB 77) and the exposure time needed to activate the monooxygenase (EROD) and conjugation (GST) enzyme systems of fish at the advanced embryonic stage were studied. Eyed stage embryos of rainbow trout (Oncorhynchus mykiss) were exposed to sublethal doses (0, 1, 10, and 100 micrograms/l) of PCB 77. Results indicated direct accumulation of the chemical into the eggs, but the exposure time was not long enough for PCB 77 to reach constant steady state. However, at the two lowest test concentrations (1 microgram/l and 10 micrograms/l) a temporary plateau at chemical accumulation was reached at the third exposure day (185 and 1221 ng PCB/g egg w.w). At the highest concentration (100 micrograms/l) the decrease in the accumulation rate was already evident after the first day (2182 ng PCB/g egg w.w). The chemical uptake increased again at day 7 in all the exposure groups. That event could have been caused by the increased metabolic rate of the embryos in preparation for the upcoming hatching event. The microsomal CYP1A monooxygenase system (EROD) was shown to be a sensitive indicator of embryonic exposure, being induced at the low (1 microgram/l, 182 ng/g egg) PCB concentration and after a short (3 day) exposure time. The conjugation enzyme system (GST) was shown to be functioning already at the advanced embryonic stage, although no response to the studied chemical stress was detected.     

Assessment of the effects of sugar cane plantation burning on daily counts of inhalation therapy

This study was designed to evaluate the association between sugar cane plantation burning and hospital visits in Araraquara in the state of S?o Paulo, Brazil. From June 1 to August 31, 1995, the daily number of visits of patients who needed inhalation therapy in one of the main hospitals of the city was recorded and used as health impairment estimation. Sedimentation of particle mass (the amount of particles deposited on four containers filled with water) was measured daily. The association between the weight of the sediment and the number of visits was evaluated by means of Poisson regression models controlled for seasonality, temperature, day of the week, and rain. We found a significant and dose-dependent relationship between the number of visits and the amount of sediment. The relative risk of visit associated with an increase of 10 mg in the sediment weight was 1.09 (1-1.19), and the relative risk of an inhalation therapy was 1.20 (1.03-1.39) on the most polluted days (fourth quartile of sediment mass). These results indicate that sugar cane burning may cause deleterious health effects in the exposed population.     

Greenhouse effect of NOX

Through various processes the nitrogen oxides (NO_X) interact with trace gases in the troposphere and stratosphere which do absorb in the spectral range relevant to the greenhouse effect (infrared wavelengths). The net effect is an enhancement of the greenhouse effect. The catalytic role of NO_X in the production of tropospheric ozone provides the most prominent contribution. The global waming potential is estimated as GWP (NO_X = 30 – 33 and 7 – 10 for the respective time horizons of 20 and 100 years, and is thereby comparable to that of methane. NO_X emissions in rural areas of anthropogenically influenced regions, or those in the vicinity of the txopopause caused by air traffic, cause the greenhouse effectivity to be substantially more intense. We estimate an additional 5–23 % for Germany’s contribution to the anthropogenic greenhouse effect as a result of the indirect greenhouse effects stemming from NO_X. Furthermore, a small and still inaccurately defined amount of the deposited NO_X which has primarily been converted into nitrates is again released from the soil into the atmosphere in the form of the long-lived greenhouse gas nitrous oxide (N₂O). Thus, anthropogenically induced NO_X emissions contribute to enhanced greenhouse effect and to stratospheric ozone depletion in the time scale of more than a century.     

Environmental chemicals and biomembranes 1. Nitrilotriacetic acid

Nitrilotriacetic acid (NTA) is readily taken up by yeast cells through simple diffusion and is metabolized. Concentrations of NTA in the millimolar range do not interfere with various membrane functions of yeast and bacteria.     

Hydroxylated PCB metabolites in nonhatched fulmar eggs from the Faroe Islands

Thirty-six polychlorinated biphenylols (OH-PCBs) congeners were characterized in Fulmar (Fulmarus glacialis) eggs collected from the Faroe Islands. The seven most abundant congeners were quantified in 19 samples, and the sigmaOH-PCB concentrations ranged between 0.92 and 4.0 ng g(-1) fresh weight (f.w.). These eggs constitute a part of the traditional diet for at least a part of the population on the Faroe Islands and may contribute to the high levels of these contaminants found in the blood of pregnant Faroese women. Because the metabolites are present in the nonhatched fulmar egg, it is concluded that the OH-PCBs are transferred to the egg before laying. High levels, 3300-18,000 ng g(-1) l.w., of sigmapolychlorinated biphenyls (PCB) were determined in the fulmar eggs, which are a considerable source for human exposure. The high PCB levels are a source for metabolic formation of hydroxylated PCBs.     

Screening of organic halogens and identification of chlorinated benzoic acids in carbonaceous meteorites

The occurrence of halogenated organic compounds measured as a sum parameter and the evidence of chlorinated benzoic acids in four carbonaceous meteorites (Cold Bokkeveld, Murray, Murchison and Orgueil) from four independent fall events is reported. After AOX (Adsorbable organic halogen) and EOX (Extractable organic halogen) screening to quantify organically bound halogens, chlorinated organic compounds were analyzed by gas chromatography. AOX concentrations varying from 124 to 209 microg Cl/g d.w. were observed in carbonaceous meteorites. Ion chromatographic analysis of the distribution of organically bound halogens performed on the Cold Bokkeveld meteorite revealed that chlorinated and brominated organic compounds were extractable, up to 70%, whereas only trace amounts of organofluorines could be extracted. Chlorinated benzoic acids have been identified in carbonaceous meteorite extracts. Their presence and concentrations raise the question concerning the origin of halogenated, especially chlorinated, organic compounds in primitive planetary matter.