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Producing valuable biochar from waste materials using thermal processes like hydrothermal carbonization (HTC) has gained attention in recent years. However, the fate of micropollutants present in these waste sources have been neglected, although they might entail the risk of environmental pollution. Thus, an HPLC-MS/MS method was developed for 12 pharmaceuticals to determine the micropollutant load of biochar, which was made from sewage sludge via HTC within 4 h at 210 °C. Pressurized liquid extraction was applied to extract the compounds. Because of the high load of co-extracted matter, matrix effects in HPLC-MS/MS were investigated using matrix effect profiles. Interfering compounds suppressed 50% of the phenazone signal in sewage sludge and 70% in biochar, for example. The quantification approaches external calibration, internal standard analysis, and standard addition were compared considering recovery rates, standard deviations, and measurement uncertainties. The external analysis resulted in decreased or enhanced recovery rates. Spiking before LC-MS/MS compensated instrumental matrix effects. Still, recovery rates remained below 70% for most compounds because this approach neglects sample losses during the extraction. Internal standards compensated for the matrix effects sufficiently for up to five compounds. The standard addition over the whole procedure proved to compensate for the matrix effects for 11 compounds and achieved recovery rates between 85 and 125%. Additionally, results showed good reproducibility and validity. Only sulfamethoxazole recovery rate remained below 70% in sewage sludge. Real sample analysis showed that three pharmaceuticals were detected in the biochar, while the corresponding sewage sludge source contained 8 of the investigated compounds.

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A fast quantification method for the determination of 11 antineoplastic drugs from wipe samples was developed using micro-scale liquid chromatography in combination with tandem mass spectrometry. The extraction efficiency from the wipes has been investigated using different extraction solvents. The results indicate that a mixture of 70/30 water/isopropanol (v/v) acidified with 0.1 % formic acid is suitable to desorb the antineoplastic drugs with sufficient recovery between 80 and 120 %. Compared to conventional liquid chromatography, the total analysis time can be reduced to 2.25 min using a 50 × 0.3 mm column at a flow rate of 25 μL min. Ion source parameters as well as the injection volume were optimized to ensure the highest sensitivity. The results of method validation showed an instrumental limit of quantification between 0.0068 and 0.0488 ng mL using an injection volume of 4.25 μL estimated by the signal to noise ratio. Moreover, the retention time repeatability was determined with a maximum relative standard deviation of 0.4 %. Graphical abstract Micro-LC-MS/MS separation of 11 antineoplastic drugs from wipe samples.

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The entry of pharmaceuticals into the water cycle from sewage treatment plants is of growing concern because environmental effects are evident at trace levels. Ozonation, UV- and UV/H(2)O(2)-treatment were tested as an additional step in waste water treatment because they have been proven to be effective in eliminating aqueous organic contaminants. The pharmaceuticals carbamazepine, ciprofloxacin, diclofenac, metoprolol and sulfamethoxazole as well as the personal care products galaxolide and tonalide were investigated in terms of degradation efficiency and by-product formation in consideration of toxic effects. The substances were largely removed from treatment plant effluent by ozonation, UV- and UV/H(2)O(2)-treatment. Transformation products were detected in all tested treatment processes. Accompanying analysis showed no genotoxic, cytotoxic or estrogenic potential for the investigated compounds after oxidative treatment of real waste waters. The results indicate that by-product formation from ozonation and advanced oxidation processes does not have any negative environmental impact.

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