The dynamics of pesticide residues in strawberries that involved quantification of pesticide residues in ripe fruits after model treatment was evaluated in repeated field trials conducted over 3 years. Sixteen commercial pesticide formulations in various combinations were employed in applications from 7 to 44 days before harvest. Altogether 21 active ingredients and some of their metabolites were determined in treated strawberries using LC-MS and GC-MS methods. Except for propargite, the concentrations of all active ingredients declined below the respective MRLs (Regulation (EC) No. 396/2005); nevertheless, most of the tested fungicides often persisted above the 0.01 mg kg⁻¹ limit required by baby food producers to avoid the risk of exceeding the 'baby food limit' established in Commission Directive 2006/141/EC. On the other hand, residues of the majority of tested insecticides, namely spinosad, pymetrozine, deltamethrin, lambda-cyhalothrin and azadirachtin, declined below this limit.

• MeSH
• biotransformace MeSH
• chemické jevy MeSH
• cyklohexany škodlivé účinky   analýza   chemie   metabolismus   MeSH
• dodržování směrnic MeSH
• dospělí MeSH
• Evropská unie MeSH
• fungicidy průmyslové škodlivé účinky   analýza   chemie   metabolismus   MeSH
• insekticidy škodlivé účinky   analýza   chemie   metabolismus   MeSH
• jahodník chemie   růst a vývoj   metabolismus   MeSH
• kojenec MeSH
• kontaminace potravin zákonodárství a právo   prevence a kontrola   MeSH
• lidé MeSH
• ovoce chemie   růst a vývoj   metabolismus   normy   MeSH
• potrava pro kojence analýza   normy   MeSH
• pyridaziny škodlivé účinky   analýza   chemie   metabolismus   MeSH
• rezidua pesticidů škodlivé účinky   analýza   chemie   metabolismus   MeSH
• spotřebitelská bezpečnost produktů * zákonodárství a právo   MeSH
• veřejná politika MeSH
• zákonodárství potravinářské MeSH
• Check Tag
• dospělí MeSH
• kojenec MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Geografické názvy
• Česká republika MeSH

In this study, levels of several groups of environmental contaminants represented by PAHs, PCBs, organochlorine pesticides and polybrominated diphenyl ethers were determined in various types of canned smoked and non-smoked fish and seafood products (54 samples) obtained from the Czech market. PAHs were detected in all of the studied samples, and at least one of the target halogenated persistent organic pollutants was present above the LOQ in 85% of the samples. The levels of PAHs, PCBs, organochlorine pesticides (mainly DDTs) and polybrominated diphenyl ethers found in the canned products varied in the range of 1.4-116 µg kg(-1), 0.6-59.6 µg kg(-1), 0.6-82.7 µg kg(-1) and 0.1-2.1 µg kg(-1) can content, respectively. Smoked sprats were the most contaminated fish product (n = 12) in which the highest levels of both PAHs and persistent organic pollutants were found. In 67% of the samples of smoked sprats in oil, the level of benzo[a]pyrene exceeded the maximum level of 5 µg kg(-1) established for smoked fish by European Union legislation. The distribution of target analytes between oil and fish fractions was also assessed. Significantly higher levels of PAHs were measured in the oil fraction.

• MeSH
• halogeny analýza   MeSH
• látky znečišťující životní prostředí analýza   MeSH
• polycyklické sloučeniny analýza   MeSH
• potrava z moře (živočišná) analýza   MeSH
• referenční standardy MeSH
• řízení kvality MeSH
• rybí výrobky analýza   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A new method for rapid determination of 73 target organic environmental contaminants including 18 polychlorinated biphenyls, 16 organochlorinated pesticides, 14 brominated flame retardants and 25 polycyclic aromatic hydrocarbons in fish and fish feed using gas chromatography coupled with triple quadrupole tandem mass spectrometry (GC-MS/MS) was developed and validated. GC-MS/MS in electron ionization mode was shown to be a powerful tool for the (ultra)trace analysis of multiclass environmental contaminants in complex matrices, providing measurements with high selectivity and sensitivity. Another positive aspect characterizing the newly developed method is a substantial simplification of the sample preparation, which was achieved by an ethyl acetate QuEChERS (quick, easy, cheap, effective, rugged and safe) based extraction followed by silica minicolumn clean-up. With use of this sample preparation approach the sample laboratory throughput was increased not only because six samples may be prepared in approximately 1 h, but also because all the above-mentioned groups of contaminants can be determined in a single GC-MS/MS run. Under the optimized conditions, the recoveries of all target analytes in both matrices were within the range from 70 to 120% and the repeatabilities were 20% or less. The method quantification limits were in the range from 0.005 to 1 μg kg(-1) and from 0.05 to 10 μg kg(-1) for fish muscle tissue and fish feed, respectively. The developed method was successfully applied to the determination of halogenated persistent organic pollutants and polycyclic aromatic hydrocarbons in fish and fish feed samples.

• MeSH
• analýza hlavních komponent MeSH
• bezpečnost potravin metody   MeSH
• kontaminace potravin MeSH
• krmivo pro zvířata normy   MeSH
• látky znečišťující životní prostředí analýza   chemie   MeSH
• limita detekce MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí * MeSH
• polycyklické aromatické uhlovodíky analýza   normy   MeSH
• řízení kvality MeSH
• ryby * MeSH
• tandemová hmotnostní spektrometrie * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A simple, fast, and cost effective sample preparation procedure has been developed and validated for the determination of 15+1 European Union Polycyclic Aromatic Hydrocarbons (15+1 EU PAHs) in dried tea leave samples. Based on a critical assessment of several sample extraction/clean-up approaches, the method based on the ethyl acetate extraction followed by the use of PAHs dedicated cartridges with molecularly imprinted polymers (MIPs) has been found as an optimal alternative in terms of time demands and obtained good extract purity. For the final identification/quantification of target PAHs, two dimensional gas chromatography coupled to a time-of-flight mass spectrometry (GC×GC-TOFMS) was used. The performance characteristics of the overall analytical method for individual PAHs determined at three spiking levels (0.5, 2.5 and 5 μg kg(-1)) were in following ranges: limits of quantitation (LOQs) 0.05-0.2 μg kg(-1), repeatabilities 2-9%, and recoveries 73-103%. The recoveries achieved by the newly developed sample preparation procedure when employed for naturally contaminated sample ("incurred" PAHs) were comparable to those obtained by other routinely used approaches employing sonication and/or pressurised liquid extraction for sample analytes isolation. The validated method was subsequently used for the determination of selected genotoxic PAHs in 36 samples of black and green tea obtained from the Czech retail market. The levels of ΣPAH4 (sum of benzo[a]anthracene (BaA), chrysene (CHR), benzo[b]fluoranthene (BbFA) and benzo[a]pyrene (BaP)) in black and green tea leaves ranged from 7.4 to 700 μg kg(-1) and from 4.5 to 102 μg kg(-1), respectively. Contamination of tested tea samples by BaP was in the range of 0.2-152 μg kg(-1).

• MeSH
• analýza nákladů a výnosů MeSH
• analýza potravin ekonomika   metody   MeSH
• bezpečnost MeSH
• čaj chemie   MeSH
• časové faktory MeSH
• extrakce na pevné fázi MeSH
• kontaminace potravin analýza   MeSH
• molekulový imprinting MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí ekonomika   metody   MeSH
• polycyklické aromatické uhlovodíky analýza   izolace a purifikace   MeSH
• polymery chemická syntéza   MeSH
• rozpouštědla chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In the presented study, comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC × GC-TOFMS) was shown to be a powerful tool for the simultaneous determination of various groups of contaminants including 18 polychlorinated biphenyls (PCBs), seven polybrominated diphenyl ethers (PBDEs), and 16 polycyclic aromatic hydrocarbons (PAHs). Since different groups of analytes (traditionally analyzed separately) were included into one instrumental method, significant time savings were achieved. Following the development of an integrated sample preparation procedure for an effective and rapid isolation of several groups of contaminants from fish tissue, the GC × GC-TOFMS instrumental method was optimized to obtain the best chromatographic resolution and low quantification limits (LOQs) of all target analytes in a complex mixture. Using large-volume programmable temperature vaporization, the following LOQs were achieved-PCBs, 0.01-0.25 μg/kg; PBDEs, 0.025-5 μg/kg; PAHs 0.025-0.5 μg/kg. Furthermore, several capillary column combinations (BPX5, BPX50, and Rxi-17Sil-ms in the first dimension and BPX5, BPX50, Rt-LC35, and HT8 in the second dimension) were tested during the experiments, and the optimal separation of all target analytes even of critical groups of PAHs (group (a): benz[a]anthracene, cyclopenta[cd]pyrene and chrysene; group (b): benzo[b]fluoranthene, benzo[j]fluoranthene and benzo[k]fluoranthene; group (c): dibenz[ah]anthracene, indeno[1,2,3-cd]pyrene and benzo[ghi]perylene) was observed on BPX5 × BPX50 column setup. Moreover, since the determination of target analytes was performed using TOFMS detector, further identification of other non-target compounds in real life samples was also feasible.

• MeSH
• analýza potravin metody   MeSH
• časové faktory MeSH
• halogenované uhlovodíky analýza   MeSH
• látky znečišťující životní prostředí analýza   MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• polycyklické aromatické uhlovodíky analýza   MeSH
• ryby metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH