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Recent decades have shown intensive studies devoted to the fate of pharmaceuticals in the environment. These studies have involved the development of analytical tools, determination of pharmaceuticals in different compartments, composting technologies, and plant uptake of pharmaceuticals. The presence of organic pollutants in sewage sludge, including pharmaceuticals, is a problem of major concern. The re-use of sewage sludge should be encouraged since it represents a long-term solution provided that the quality of the sludge re-used is compatible with public health and environmental protection requirements. Composting is a widely recognized way of making the soil application of sewage sludge safer. In this study, the impact of sewage sludge composting on the degradation of metformin (MET), by far the most often prescribed antidiabetic drug worldwide, and carbamazepine (CBZ), a poorly biodegradable but widely used as an anticonvulsant drug to cure depression and seizures, were analysed. The anaerobically digested and dewatered sewage sludge samples were collected from municipal wastewater treatment plant. Composting experiments were performed under fixed conditions during 30 days. The results of the experiment showed that during a 1-month composting period more than 90% of MET residues degraded, but no degradation of CBZ took place during the composting period. The half-life of MET was 3 days for the compost mixture with the ratios of 1:3 and 1:2 (v:v). The results of this study show that composting maylead to the efficient degradation of MET, whereas for the elimination of CBZ from sewage sludge different means should be used. [ABSTRACT FROM AUTHOR]

This review is to reflect the work addressed to the application of biosolids and especially sewage sludge as a resource in composting. A considerable drop in the use of P fertilisers can be followed since early 1990s. Due to this fact crop production in Estonia takes place at the expense of soil phosphorous (P) resources. One of the ways of increasing the fertility of agricultural lands is to use nutrient-rich sewage sludge. Unfortunately, this may cause several undesired consequences due to biological and chemical contaminants. The presence of some widely used pharmaceuticals, as ciprofloxacin (CIP), norfloxacin (NOR), ofloxacin (OFL), sulfadimethoxine (SDM) and sulfamethoxazole (SMX), was evident in sewage sludge of the two Estonian largest cities, Tartu and Tallinn. The concentrations of pharmaceuticals decreased after sewage sludge digestion and composting, but they were still present in detectable amounts. Sewage sludge co-composting experiments with sawdust, peat and straw showed the degradation of fluoroquinolones (FQ) and sulfonamides (SA). Additions of sawdust clearly speeded up this process, whereas the mixtures with peat and straw performed lower abilities to decompose pharmaceutical residues. Novel methodologies were developed and experiments conducted to study the potential accumulation of fluoroquinolones FQs and SAs by food plants. Due to the low adsorption of SAs on soil particles they are 'free' to migrate into plants. Different behaviour is characteristic to FQs as they are accumulated in sludge. Recent years have also shown progress in vermicomposting work and in using compost in afforestation. [ABSTRACT FROM AUTHOR]

A simultaneous method for quantitative determination of traces of fluoroquinolones (FQs) and sulfonamides (SAs) in edible plants fertilized with sewage sludge was developed. The compounds were extracted from the plants by rapid and simple liquid extraction followed by extracts clean-up using solid phase extraction. The eluent additive 1,1,1,3,3,3-hexafluoro-2-propanol was used for liquid chromatographic detection to achieve separation of structurally similar antimicrobials like ciprofloxacin and norfloxacin. Identification and quantification of the compounds were performed using high-performance liquid chromatography with electrospray ionization mass spectrometry in selected reaction monitoring mode. Method was validated and extraction recoveries of FQs and SAs ranged from 66% to 93%. The limit of quantifications was from 5 ng/g in the case of ofloxacin to 40 ng/g for norfloxacin. The method precision ranged from 1.43% to 2.61%. The developed novel method was used to evaluate the plats antimicrobial uptake (potato (Solanum tuberosum L .) , carrot (Daucus carota L .) , lettuce (Lactuca sativa L .) , and wheat (Triticum vulgare L .) ) from soil and migration of the analytes inside the plants.