A new analytical method for determining environmental pesticide residues in pollen was introduced and validated. The extraction was conducted using acetonitrile, the clean-up using Supelclean Ultra ...2400 solid phase extraction cartridges, which contain Grapsphere, anion exchanger, C18 and zirconia-based sorbent, and the determination was conducted using gas chromatography coupled with mass spectrometry. The method was applied in practice. A total of 49 active substances (pesticides) were sought in 30 bee pollen samples gathered from Slovenian beekeepers from all 12 statistical regions of Slovenia. The fungicide azoxystrobin was the only active substance found and was found only in one sample with a concentration of < 0.05 mg kg-1. The active substances sought were not detected in 96.7 % of the samples analysed. The risk assessment revealed that the analysed pollen samples do not represent an unacceptable risk for consumers. The results were compared with those from the literature and the outcome was that bee pollen from Slovenia contained a lower number of active substances at mainly lower contents as compared pollen from some other European countries.
New analytical methods for the determination of pesticide residues in wine were introduced and validated. Extraction was performed with sorption of the active substances on the stir bar and ...determination by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry. The methods were applied in practice. A total of 77 active substances were searched for in 42 wine samples from all 3 wine-growing regions of Slovenia. The fungicides dimethomorph, fludioxonil and pyraclostrobin were found in 78.6% of all analysed samples. The risk assessment concluded that the analysed wine samples do not pose an unacceptable risk to consumers. The results were compared with previous studies.
Gas chromatography coupled with mass spectrometry was used for the introduction and validation of the multiresidual method for determining of plant protection product residues in strawberries. During ...the validation procedure, limits of quantification were set and the method was checked for its recovery, linearity, repeatability, reproducibility and measurement uncertainty. An interlaboratory comparison was also performed to check the accuracy of the method. The method was proven to be fit for purpose. Afterwards 19 strawberry samples were analysed for the presence of plant protection product residues using the validated method. In the strawberries 5 active substances, all fungicides, were found: chlorothalonil, cyprodinil, fludioxonil, metalaxyl+metalaxyl-M and pyrimethanil. Residues of these active substances were in range 0.01 – 0.44 mg/kg. No cases exceeding the maximum residue levels were measured.
Rastućom primjenom antimikrobnih lijekova u humanoj i veterinarskoj medicini povećava se i njihova prisutnost u okolišu pa tako i u otpadnim vodama što izaziva veliku zabrinutost u javnosti. Najčešće ...primjenjivane skupine antimikrobnih lijekova su makrolidi, tetraciklini, kinoloni te sulfonamidi i trimetoprim. Brojnim istraživanjima dokazan je njihov štetan utjecaj na vodene organizme i biljni svijet, a najveći problem prisutnosti antibiotika i njihovih ostataka u okolišu je pojava i širenje rezistencije bakterija na antibiotike. Zbog navedenih razloga vrlo je važno osigurati kvalitetnu, pouzdanu i osjetljivu analitičku metodu koja može dati nedvojbeni uvid u stanje antibiotika u vodi. U ovom preglednom radu prikazana je primjena vezanog sustava tekućinske kromatografije visoke djelotvornosti sa spektrometrijom masa (LC-MS/MS) koji se najčešće upotrebljava zbog svoje specifičnosti, brzine, osjetljivosti i pouzdanosti kao i tijek priprave, ekstrakcije te pročišćavanja analita u uzorku tijekom multirezidualne analize. Zbog prirode matrice (otpadna voda) pročišćavanje se provodi SPE, SPME ili kapilarnom SPME tehnikom nakon koje slijedi analiza LC-MS/MS. Molekule analita u uzorku podliježu ionizaciji elektroraspršenjem (ESI), a primjenom spektrometra masa s više analizatora, trostrukog kvadrupola moguće je određivanje vrlo malih koncentracija analita, a ujedno i strukture određene ciljne molekule.
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