Determination of pharmaceuticals in sewage sludge by pressurized liquid extraction (PLE) coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS)

Abstract

In this study, we aimed at optimizing a sensitive and reliable method for a simultaneous determination of 31 pharmaceuticals belonging to predominant therapeutic classes identified in different types of sewage sludge proceeding from conventional and advanced wastewater treatment. Freeze-dried sewage sludge was extracted by pressurized liquid extraction technique using accelerated solvent extractor Dionex 300. In order to minimize interferences with matrix components and to preconcentrate target analytes, solid phase extraction was introduced in the method as a clean-up step. The entire method was validated for linearity, precision, accuracy, and method detection limits (MDLs). The method turned out to be specific, sensitive, and reliable for the analysis of sludge of different composition, type, and retention time in the process. The developed sample preparation protocol and previously published method for LC-MS/MS analysis (Gros et al., Talanta 70:678-690, 2006) were successfully applied to monitor the target pharmaceuticals in different types of sewage sludge, i.e., primary sludge, secondary sludge, treated sludge, and sludge proceeding from pilot-scale membrane bioreactors (MBRs) operating in parallel to the conventional activated sludge treatment. Among the investigated pharmaceuticals, 20 were detected in the sludge proceeding from full-scale installations, whereas the MBR sludge concentrations were below MDLs for several compounds. The highest concentrations were recorded for treated and primary sludge. For example, the mean concentration of ibuprofen in the digested sludge was 299.3 +/- 70.9 ng g(-1) dw, whereas in the primary sludge, it was enriched up to 741.1 ng g(-1) dw. Other pharmaceuticals detected at relatively high concentrations were diclofenac, erythromycin, glibenclamide, ketoprofen, ofloxacin, azithromycin (up to 380.7, 164.2, 190.7, 336.3, 454.7, 299.6 ng g(-1) dw in the primary sludge, respectively), gemfibrozil, loratidine, and fluoxetine (up to 189.1, 189.7 and 174.1 ng g(-1) dw in the treated sludge, respectively).

Occurrence, distribution and potential affecting factors of antibiotics in sewage sludge of wastewater treatment plants in China

“…The concentrations of macrolides detected in the sludge in this study were lower than those previously reported in Hong Kong (ERY: 63 μg/kg) (Xu et al, 2007), USA (ERY: 41 μg/kg) (Kinney et al, 2006) and Spain (ERY: 62.5 μg/kg; TYL: 1074 μg/kg) (Radjenović et al, 2009), indicating that the levels of macrolides pollution in this study were relatively low.…”

“…However, the concentrations of some quinolones in the sludge were at least ten times higher than those in Hong Kong (OFL: 835 μg/kg; NOR: 372 μg/kg) (Xu et al, 2007), Japan (NOR: 87 μg/kg) (Okuda et al, 2009), Estonian (OFL: 4-10.9 μg/kg; NOR: 20.8-25.0 μg/kg; CIP: 32.8-35.5 μg/kg) (Lillenberg et al, 2009), Italy (OFL: 3.4 μg/kg) (Zuccato et al, 2010) and Spain (OFL: 8.4 μg/kg) (Radjenović et al, 2009), indicating that the levels of quinolone pollution in China were relatively high.…”

“…It was reported that the concentrations of antibiotics ranged from μg/kg to a few mg/kg in sewage sludge from different countries, such as Estonian (Lillenberg et al, 2009), Italy (Zuccato et al, 2010), Spain (Nieto et al, 2010;Radjenović et al, 2009), Switzerland (Göbel et al, 2005), USA (Kinney et al, 2006), Japan (Okuda et al, 2009) and China (Xu et al, 2007). In China, there are over 30 million tons of sewage sludge (moisture content: 80%) generated in 2011, and 75-85% of them cannot be safely disposed (Zou and Wang, 2012).…”

Determination of emerging contaminants in environmental matrices

“…Moreover, sewage sludge Radjenovic et al, 2009a;Ternes et al, 1999) from WWTPs and animal litter or manure (Hanselman et al, 2003;Kjaer et al, 2007;Topp et al, 2010) from farms are used in agricultural soils to increase their content in organic matter and nutrients, but ECs may be also introduced into the agricultural soils (Chen et al, 2013;Vazquez-Roig et al, 2012). Finally, inappropriate disposal of these compounds is another source that cannot be neglected (Yu and Wu, 2012).…”

“…naproxen, diclofenac, ketoprofen, and ibuprofen) (Dobor et al, 2010;Saleh et al, 2011), however recent studies have included many more compounds belonging to several therapeutic classes that exhibit very different physico-chemical properties (Jelic et al, 2009;Peysson and Vulliet, 2013;Radjenovic et al, 2009a).…”