Direct injection Fourier transform ion cyclotron resonance mass spectrometric method for high throughput quantification of quinolones in poultry.

Many recent studies have shown high detection frequencies of quinolone antibiotics in poultry, as well as an increasing incidence of antimicrobial resistance. The main purpose of this project was to develop a fast and reliable analytical method for the detection of quinolones in poultry meat. In order to develop a rapid quantitative confirmation method, ion cyclotron resonance mass spectrometer was used. First, the sample preparation procedure was simplified by reducing the procedure to extraction and freezing out steps. Second, the chromatographic separation step was excluded and mass spectrometric parameters were optimised. Third, the method was validated by fortifying a blank matrix at four levels (0.5, 1, 1.5, and 2 times the maximum residue limit (MRL) or level of interest in those cases when no MRL was established). As a result, the overall analysis time was reduced to less than an hour. The validation study revealed that the method is capable of detection and confirmation of ten quinolone compounds in poultry above the detection capability (CCß) of the procedure. Finally, the developed method was applied to 19 commercially available chicken meat samples. None of the samples contained quinolones above the limit of quantification (LOQ) of the method. Analysis of treated chickens revealed that the developed method is suitable for the determination of ciprofloxacin and enrofloxacin. The developed method could be one of the fastest quantitative confirmatory methods for the analysis of quinolones available so far.

Determination of residues and metabolites of more than 140 pharmacologically active substances in meat by liquid chromatography coupled to high resolution Orbitrap mass spectrometry.

This study reports an analytical method for simultaneous identification, screening and quantification of 164 residues and metabolites of pharmacologically active substances belonging to such therapeutic classes as anti-infectious (antibiotics and chemotheurapeutics), anti-inflammatory and antiparasitic agents (against protozoa, endo- and ectoparasites), corticoids and agents acting on the nervous and reproductive systems, substances with hormonal and thyreostatic action, and beta agonists. Different sample preparation procedures were compared and optimised for the detection of selected veterinary drugs in chicken, porcine and bovine meat by ultra-high performance liquid chromatography coupled to high-resolution Orbitrap mass spectrometry. The optimised instrumental method and sample preparation procedures were validated by fortifying blank matrix at four levels (0.5, 1.0, 1.5, and 2 times the maximum residue limit (MRL)), or at concentrations as low as possible for substances without an MRL. The evaluated performance parameters were selectivity, matrix effect, method and instrument limits of quantification, accuracy, and repeatability. A total of 130 selected compounds in chicken meat, 127 compounds in bovine meat and 123 compounds in porcine meat samples could be quantified with accuracy ranging from 70 to 120% and RSDs less than 30%. Finally, the method was successfully used to detect and quantify veterinary drug residues in real samples found to be suspect using the non-selective qualitative test for the detection of inhibitor substances. The results were confirmed using the relevant one-residue confirmatory methods revealing concentrations of residues higher than MRLs established for several samples.

Occurrence of polybrominated diphenyl ethers, perfluorinated compounds, and nonsteroidal anti-inflammatory drugs in freshwater mussels from Latvia.

The occurrence of polybrominated diphenyl ethers (PBDE), perfluorinated compounds (PFC), and nonsteroidal anti-inflammatory drugs (NSAID) in Latvian freshwater ecosystems was evaluated by using filter-feeding mussels as bioindicators. Twenty four samples of mussels were collected from freshwater bodies throughout the territory of Latvia during the summer of 2017. PBDE contamination was ubiquitous, reaching the highest total concentration of 193.2 pg g-1 w.w. BDE-209 was the most abundant compound, followed by penta-BDE components BDE-49, -100, -99, -153, -154, and -47 in decreasing order. The levels of PFCs in Latvian mussels were generally lower than those reported from other regions. Perfluorooctanoic acid (PFOA) was more common in mussels than perfluorooctane sulfonate (PFOS). Ibuprofen was the only NSAID detected in mussels during this study (detection frequency 50%). The observed concentrations of this compound varied between 0.52 and 109 ng g-1 w.w., being noticeably higher than reported by other authors. Overall, the results indicate that among the three analysed groups of contaminants, ibuprofen is present in Latvian freshwater environment at relatively high levels and further monitoring should be carried out.

Emerging brominated flame retardants and dechlorane-related compounds in European eels (Anguilla anguilla) from Latvian lakes.

Fifteen halogenated flame retardants (HFRs) including seven emerging brominated flame retardants (EBFRs) and eight dechlorane-related compounds (DRCs) were analyzed in eels (Anguilla anguilla) sampled from five Latvian lakes. Out of the seven EBFRs, hexabromocyclododecane (HBCD) and decabromodiphenyl ethane (DBDPE) were found in eels in quantifiable concentrations, up to 6.58 and 33.0 ng g-1 lipid weight (l.w.), respectively. The mean total concentration of DRCs (∑DRC) in the samples was 0.62 ng g-1 l.w. and the geographical distribution of DRC contamination was nearly uniform among the selected lakes. Dechlorane 602 (Dec 602) was the predominant component, whereas the composition of mixture containing syn- and anti-Dechlorane Plus (DP) stereoisomers showed a pronounced enrichment of the anti-DP isomer and was close to the composition of OxyChem® DP commercial product. The determined concentrations of HFRs were lower than in other studies of aquatic biota from Europe and Asia, and the obtained results reflect the acceptable environmental status of Latvian lakes with regard to the total content of HBCD (∑HBCD), considering the environmental quality standards (EQS) stated in the Directive 2013/39/EU. The highest ∑HBCD levels were observed in eels from lakes corresponding to the industrialization of those areas, while the results of principal component analysis (PCA) showed that the concentration of HBCD depended on the particular sampling lake, reflecting non-uniform contamination of the Latvian environment with this EBFR.

Brominated flame retardants and toxic elements in the meat and liver of red deer (Cervus elaphus), wild boar (Sus scrofa), and moose (Alces alces) from Latvian wildlife.

In order to evaluate the contamination status of terrestrial biota in Latvia, muscle and liver tissues of red deer (Cervus elaphus), wild boar (Sus scrofa), and moose (Alces alces) were analyzed for the content of polybrominated diphenyl ethers (PBDE), hexabromocyclododecane (HBCD), tetrabromobisphenol A (TBBPA), as well as cadmium and lead. The highest mean concentrations of PBDEs (46.6pgg-1 wet weight (w.w.)), cadmium (0.95mgkg-1 w.w.), and lead (0.22mgkg-1 w.w.) were observed in the tissues of moose, while the wild boar samples contained the highest levels of HBCD, with the mean concentration equal to 264pgg-1 w.w. in muscle tissues. Generally low mean concentrations of TBBPA from 0.52 to 4.54pgg-1 w.w. were observed. The liver tissue of all analyzed specimens was found to contain higher concentrations of contaminants, compared to muscle tissue. The congener profile of PBDEs in the analyzed tissues indicated that the recently used "penta-BDE" formulation was a probable source, while components of HBCD, "octa-BDE", and "deca-BDE" technical mixtures are likely to undergo congener-specific or diastereomer-specific bioaccumulation or metabolic degradation. Considering the reports from other regions, it can be concluded that the terrestrial biota in Latvia is less affected by the studied contaminants.