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The selective serotonin reuptake inhibitors citalopram, sertraline, paroxetine, fluvoxamine and fluoxetine have been investigated in 10 l anaerobic lab-scale digesters with continuous stirring and mesophilic conditions at 37 °C to investigate whether they would be reduced or accumulated in sewage sludge depending on whether the bacteria present were able to use the SSRIs as a carbon source or not. The total SSRI concentration had a significant reduction in concentration during the anaerobic treatment process from theoretically 0.58 mg/l to 0.21 mg/l after 17 days. However, large differences in the reduction of the different compounds were found. Paroxetine and citalopram were found to be almost completely reduced at day 24 with reductions of 85% (citalopram) and 98% (paroxetine). Reductions of 32% (fluoxetine), 53% (fluvoxamine) and 38% (sertraline) indicate that these three compounds have a higher potential for accumulation. None metabolites of these compounds were found in the samples., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Sewage and sewage sludge is known to contain pharmaceuticals, and since sewage sludge is often used as fertilizer within agriculture, the reduction of the selective serotonin reuptake inhibitors (SSRIs) Citalopram, Sertraline, Paroxetine, Fluvoxamine and Fluoxetine during composting has been investigated. Sewage sludge was spiked with the SSRIs before the composting experiment started, and the concentration of the SSRIs in the sludge during a 21 day composting period was measured by liquid phase microextraction (LPME) and high-performance liquid chromatography-mass spectrometry. All the SSRIs had a significant decrease in concentration during the composting process. The highest reduction rates were measured for Fluoxetine and Paroxetine and the lowest for Citalopram. In addition three out of four known SSRI metabolites were found in all the samples, and two of them showed a significant increase in concentration during the composting period.

A method for the determination of five selective serotonin reuptake inhibitors (citalopram, sertraline, fluoxetine, fluvoxamine and paroxetine) and four of their metabolites (desmethylcitalopram, didesmethylcitalopram, norfluoxetine and desmethylsertraline) in seawater and sewage influents and effluents, has been developed and validated. The method is based on a three-phase hollow-fibre supported liquid phase microextraction of 1.1L samples, followed by high performance liquid chromatography with electrospray ionization and mass spectrometric detection. The detection limits varied between 17 pg/L (citalopram) and 618 ng/L (desmethylsertraline), and the quantification limits between 57 pg/L (citalopram) and 4.1 ng/L (desmethylsertraline). Sampling was done from February to August in 2007 on three different locations with dissimilarities concerning waste water treatment procedures. No significant difference in SSRI cleansing efficiency between merely sieving (Langnes STP, Tromsø) and a more advanced sewage treatment (VEAS STP, Oslo) was seen. All the investigated compounds are present in all waste water samples from these STPs, and a total concentration of SSRIs and metabolites up to 840 ng/L has been found. Untreated sewage samples have been collected in the small town Longyearbyen at Spitsbergen. Despite few inhabitants (2000), it was still possible to find traces of SSRIs in the waste water. In Tromsø and Longyearbyen the waste water is discharged into the sea, therefore seawater samples have been collected close to the outlets. The results show higher concentrations of SSRIs outside Longyearbyen than Tromsø, possibly due to the stronger tidal currents around Tromsø. However, the concentrations are quite low, not exceeding total concentrations of 3 ng/L.

An analytical method for quantification of the selective serotonin reuptake inhibitors (SSRIs) citalopram, sertraline, paroxetine, fluoxetine and fluvoxamine in sewage influents and effluents from selected sewage treatment plants (STPs) has been developed and validated. This quantification method is based on solid phase extraction of 2.5L samples, followed by liquid-liquid extraction for further sample clean up in order to minimize matrix effects during subsequent quantification. The samples were analysed on a high performance liquid chromatograph coupled to a triple quadrupole mass spectrometric detector using 0.1% ammonia in acetonitrile/water as mobile phase, with positive electrospray ionisation and multiple reaction monitoring for detection and quantification. 1-[3-(10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)propyl]-pyrrolidine (N-7084) was used as internal standard for quantification. The recovery rates of the SSRIs ranged between 54 and 84%, and the method limit of quantification (MLQ) was between 120 and 290 pg/L for the target compounds. Samples were collected in July 2005 from three different STPs and a pump station in Tromsø, Northern Norway. Two of the STPs serve the University hospital and its psychiatric department, respectively, in addition to domestic sewage. SSRIs were detected in all samples collected. The concentrations varied greatly from below the MLQ to several hundreds ng/L. Concentrations in influents were higher compared to filtered effluents, indicating that SSRIs adsorb to particulate matter, are degraded by microorganisms, or degraded in other ways during the filtration process. However, more samples should be analysed before general conclusions can be drawn.