Jozef Ryba

National study of illicit drug use in Slovakia based on wastewater analysis

The aim of this study was to analyze illicit drugs and their metabolites in wastewater from eight selected wastewater treatment plants (WWTPs) in Slovakia. The effect of two of the biggest music festivals in Slovakia on illicit drugs in wastewater was also investigated. Urinary bio-markers of amphetamine, methamphetamine, cocaine, cannabis and ecstasy use were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We then compared our results with data obtained in other parts of Europe and the world. This study demonstrates that Slovakia has one of highest methamphetamine consumption rates in Europe. Within Slovakia, the highest level of methamphetamine consumption was found in Petržalka, where the mean specific load of this drug in sewage was 169 mg/day/1000 inhabitants; the next highest loads were detected in Piešťany (128 mg/day/1000 inhabitants) and Bratislava (124 mg/day/1000 inhabitants). Amphetamine, ecstasy and cannabis consumption in our study were comparable to that found in other European cities, whereas cocaine consumption was lower. We also analyzed the pattern of drug consumption over the course of a week. The load of the cocaine metabolite benzoylecgonine in wastewater increased during the weekend. The use of this drug was most common in the capital of Slovakia. Increased consumption was also found during a folk festival in Piešťany. The ecstasy load in wastewater from larger cities also significantly increased over the weekend. An increase of drug consumption was also detected during a music festival in Trenčín, especially for ecstasy. The specific load of ecstasy during this festival increased from 3mg/day/1000 inhabitants to 29 mg/day/1000 inhabitants. The possible influence of music styles on the consumption of certain drugs was also observed. During a folk festival, methamphetamine and cocaine were more commonly used.

Pilot study of seasonal occurrence and distribution of antibiotics and drug resistant bacteria in wastewater treatment plants in Slovakia.

This work presents environmental and quality-control data from the analyses of 33 antibiotics in influent and effluent water from two waste water treatment plants (WWTPs) in the capital and the biggest city of Slovakia. Seeing that consumption of antibiotics depends on epidemiological season, samples were collected during February and August. Among assessed antibiotics ciprofloxacin and clarithromycin were detected in highest concentrations in influent water. Seasonal changes were observed only in plant A when antibiotic concentrations decreased. On the other hand an increase in some cases was observed in plant B. Insufficient degradation of some macrolides, sulfonamides and trimethoprim was detected according to their higher concentrations in effluent water. Contact of antibiotics in subinhibitory concentrations and sludge bacteria in WWTPs represent the base for the development of significant levels of microbial resistance. Simultaneously, antibiotic resistance of fecal coliforms and fecal streptococci from sewage sludge was evaluated. Majority of coliform bacteria were found to be resistant to ampicillin and gentamicin. A significant seasonal difference was determined only in case of high-level resistance. In summer samples, an increase in the strains resistant to concentrations higher than the resistance breakpoints established by EUCAST and NCCLS was observed. No antibiotic resistance in streptococci was observed. However, as a part of sewage sludge is mixed with compost and utilized in agriculture, better processing of sludge should be considered.

Biodegradation of Benzo[a]Pyrene through the use of algae

AbstractIn this work for disposal of the biologically hard decomposed pollutant Benzo[a]Pyrene (BaP) photooxidation Chlorella kessleri was used. The simulation model system under the different experimental conditions (varying biomass and light intensity) was evaluated. For quantitative analysis of the decrease in BaP, GC/MS technique was used. The highest degradation efficiency was achieved in the case of biomass from the culture of live algae (29%) and light intensity at level of 13.5 W m−2. When the dry biomass was used, degradation under the same conditions was lower because of lack of enzymatic activity in the system.

Treatment of industrial wastewater with high content of polyethylene glycols by Fenton-like reaction system (Fe0/H2O2/H2SO4)

Abstract The Fenton-like reaction (FLR) as advanced oxidation process system was successfully applied in the industrial wastewater pre-treatment with high content of polyethylene glycols (PEGs). Our effort was focused on the monitoring of efficiency of chemical oxygen demand (COD) removal in untreated and pre-treated wastewater using FLR (Fe0/H2O2/H2SO4) and also identification of products after treatment process. The influence of FLR pre-treatment on the biological treatment step was also studied. It was found that the COD value removal in untreated wastewater was only 37%, whereas in pre-treated wastewater the COD removal achieved 84%. High-performance liquid chromatography data have shown that during FLR the low-molecular fragments of PEGs are formed. It was also observed that high initial COD value was considerably decreased.