What is in the fish? Collaborative trial in suspect and non-target screening of organic micropollutants using LC- and GC-HRMS.

A collaborative trial involving 16 participants from nine European countries was conducted within the NORMAN network in efforts to harmonise suspect and non-target screening of environmental contaminants in whole fish samples of bream (Abramis brama). Participants were provided with freeze-dried, homogenised fish samples from a contaminated and a reference site, extracts (spiked and non-spiked) and reference sample preparation protocols for liquid chromatography (LC) and gas chromatography (GC) coupled to high resolution mass spectrometry (HRMS). Participants extracted fish samples using their in-house sample preparation method and/or the protocol provided. Participants correctly identified 9-69 % of spiked compounds using LC-HRMS and 20-60 % of spiked compounds using GC-HRMS. From the contaminated site, suspect screening with participants' own suspect lists led to putative identification of on average ∼145 and ∼20 unique features per participant using LC-HRMS and GC-HRMS, respectively, while non-target screening identified on average ∼42 and ∼56 unique features per participant using LC-HRMS and GC-HRMS, respectively. Within the same sub-group of sample preparation method, only a few features were identified by at least two participants in suspect screening (16 features using LC-HRMS, 0 features using GC-HRMS) and non-target screening (0 features using LC-HRMS, 2 features using GC-HRMS). The compounds identified had log octanol/water partition coefficient (KOW) values from -9.9 to 16 and mass-to-charge ratios (m/z) of 68 to 761 (LC-HRMS and GC-HRMS). A significant linear trend was found between log KOW and m/z for the GC-HRMS data. Overall, these findings indicate that differences in screening results are mainly due to the data analysis workflows used by different participants. Further work is needed to harmonise the results obtained when applying suspect and non-target screening approaches to environmental biota samples.

Spatial distribution and temporal trends of pharmaceuticals sorbed to suspended particulate matter of German rivers.

Although several studies confirmed a wide distribution of pharmaceuticals in rivers and streams, a limited knowledge is available about the partitioning of pharmaceuticals between the water phase and suspended particulate matter (SPM). To close this gap of knowledge, we developed and validated a sensitive and high throughput analytical method for the analysis of 57 pharmaceuticals, 42 metabolites and transformation products (TP) as well as the artificial sweetener acesulfame sorbed to SPM. The method was based on pressurized liquid extraction (PLE) followed by a clean-up via solvent exchange and detection via direct injection-reversed phase LC-MS/MS and freeze-drying-HILIC-MS/MS. Freundlich isotherms were determined for 90 analytes. All showed a linear sorption behavior. Distribution coefficients (Kd) ranged from 0.64 L/kg to 9300 L/kg. For 18 pharmaceuticals, Kd values were found to be above 100 L/kg. SPM of annual composite samples were analyzed to determine the pharmaceutical concentrations between 2005 and 2015 at four sites of the river Rhine: Weil, Iffezheim, Koblenz and Bimmen as well as between 2006 and 2015 at one site of the river Saar, at Rehlingen. In these SPM samples, up to 61 of the 100 analytes were detected with concentrations up to 190 ng/g d.w. (dry weight) for guanylurea, a transformation product of the antidiabetic metformin. For most analytes, increasing concentrations were found along the length of the Rhine and higher concentrations were measured in Rehlingen/Saar. Normalization of the data with the antiepileptic drug carbamazepine as an intrinsic tracer for municipal wastewater indicated possible industrial discharges for four analytes. For most pharmaceuticals, the annual concentrations exhibited a good correlation with the consumption volumes in Germany.

Development of an analytical method to quantify pharmaceuticals in fish tissues by liquid chromatography-tandem mass spectrometry detection and application to environmental samples.

A sensitive multiresidue method was developed to quantify 35 pharmaceuticals and 28 metabolites/transformation products (TPs) in fish liver, fish fillet and fish plasma via LC-MS/MS. The method was designed to cover a broad range of substance polarities. This objective was realized by using non-discriminating sample clean-ups including separation technique based on size exclusion, namely restricted access media (RAM) chromatography. This universal clean-up allows for an easy integration of further organic micropollutants into the analytical method. Limits of quantification (LOQ) ranged from 0.05 to 5.5 ng/mL in fish plasma, from 0.1 to 19 ng/g d.w. (dry weight) in fish fillet and from 0.46 to 48 ng/g d.w. in fish liver. The method was applied for the analysis of fillets and livers of breams from the rivers Rhine and Saar, the Teltow Canal as well as carps kept in fish monitoring ponds fed by effluent from municipal wastewater treatment plants. This allowed for the first detection of 17 analytes including 10 metabolites/TPs such as gabapentin lactam and norlidocaine in fish tissues. These results highlight the importance of including metabolites and transformation products of pharmaceuticals in fish monitoring campaigns and further investigating their potential effects.

Utilization of large volume zwitterionic hydrophilic interaction liquid chromatography for the analysis of polar pharmaceuticals in aqueous environmental samples: Benefits and limitations.

Benefits and limitations of HILIC were studied for the analysis of extreme polar organic contaminants in aqueous environmental matrices. A sensitive analytical method was developed and validated for the detection of 11 pharmaceuticals, 15 pharmaceutical metabolites and transformation products and the artificial sweetener acesulfame in aqueous environmental samples. The analytical method consisted of a simple and non-specific sample preparation based on freeze-drying followed by detection with large injection volume (70 µL) zwitterionic HILIC-ESI-MS/MS. Robustness studies showed a high sensitivity of the retention times and peak shapes to variations of the acetonitrile/water ratio of both the eluent and the diluent. Thus, a thorough sample and eluent preparation is required to obtain reproducible results. Extreme matrix effects of >200% were observed for emtricitabine and acyclovir, which could be traced to the co-elution of nitrate and chloride, respectively. These matrix effects and those of other analytes could be efficiently compensated by using deuterated, 13C and 15N-labeled internal standards. The developed method was able to detect the selected 27 analytes in treated wastewater, surface water and groundwater down to limit of quantification (LOQ) in the lower ng/L range. Appreciable concentrations were detected, ranging up to 110 µg/L (guanyl urea) in treated wastewater, up to 5.1 µg/L (oxipurinol) in surface water and up to 6.1 µg/L (acesulfame) in groundwater. In a German drinking water, only the X-ray contrast medium diatrizoate and the artificial sweetener acesulfame were quantified above LOQ with 0.19 µg/L and 0.35 µg/L, respectively.