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The occurrence and concentrations of organochlorine pesticides and polychlorinated biphenyls (PCBs) were determined in 158 muscle samples of bream (Abramis brama) and roach (Rutilus rutilus), and 84 samples of sediments collected from 10 river and lake sampling sites in 2011 and 2012. The concentrations of DDTs (p,p'-DDT, o,p'-DDT, p,p'-DDE, and p,p'-DDD), HCH isomers (α-, ß-, and γ-HCH), HCB, and PCBs (six indicator PCB congeners 28, 52, 101, 138, 153 and 180) were determined using the capillary gas chromatography. The mean concentrations of DDTs in bream and roach were in the range of 11.2-654 and 4.5-121 µg/kg wet weight respectively, and PCBs were in the range of 1.3-75.9 and 1.1-112 µg/kg wet weight, respectively. Mean concentrations of DDTs and PCBs in sediments were 0.5-270 µg/kg dry weight and <0.1-2.2 µg/kg dry weight respectively. The study showed clear spatial differences in the levels of organochlorine pesticides and PCBs in fish and sediments from different aquatic ecosystems. The highest levels of contaminants were detected in fish and sediments from the Vistula River in vicinity of Cracow. The possible risk to the fish meat consumers and ecological risk were evaluated.
This survey provides a general discussion on drug residue analysis in biological material. Quality criteria for the use of thin layer chromatography in residue analysis have been evaluated and compared with those of other methods. The present application of TLC in residue analysis of antibacterials, growth promoters and neuroleptics has been discussed.
The occurrence and concentrations of organochlorine pesticides and polychlorinated biphenyls (PCBs) were determined in 141 adipose tissue samples of wild boars, roe deer, and red deer from different regions of the country, collected in 2010/2011. The determinations of HCH isomers (α-, ß-, and γ-HCH), HCB, DDTs (p,p'-DDT, o,p'-DDT, p,p'-DDE, and p,p'-DDD), and PCBs (six indicator PCB congeners 28, 52, 101, 138, 153, and 180) were carried out using the capillary gas chromatography. The mean concentrations of DDTs expressed on the fat basis ranged from 0.241 mg/kg (wild boar) to 0.032 mg/kg (red deer), and for PCBs from 0.015 mg/kg (wild boar) to 0.010 mg/kg (roe deer). The mean contribution of p,p'-DDE to DDTs and PCB 153, PCB 138, and PCB 180 to PCBs exceeded 80% and 90% respectively, in all game animal samples studied. Higher contents of chlorinated hydrocarbons were detected in game animals originating from industrial regions.
The occurrence and levels of organochlorine pesticides and polychlorinated biphenyls (PCB) were determined in herring, sprat and salmon from the southern Baltic Sea, collected in the period 2006-2009. The determinations of HCH isomers (alpha-, beta- and gamma-HCH), HCB, ∑-DDT (p,p’-DDT, o,p’-DDT, p,p’-DDE and p,p’-DDD) and ∑-PCB (seven indicator PCB congeners 28, 52, 101, 118, 138, 153 and 180) were carried out using capillary gas chromatography. The mean concentrations of ∑-DDT expressed on whole weight basis ranged from 25.7 µg/kg (herring) to 64.4 µg/kg (salmon), and for ∑-PCB from 15 µg/kg (herring) to 39.4 µg/kg (salmon). The levels of ∑-DDT and ∑-PCB were about 2.5-fold higher in the muscle of salmon than in muscle of other fish species. The mean contribution of p,p’-DDE to the sum of DDT and PCB 153 and PCB 138 to the sum of PCB exceeded 60% in all fish samples studied. No differences in contamination levels among the years of study were observed.
The aim of our study was to assess the occurrence and to determine the concentrations of organochlorine pesticides and indicator PCB congeners in muscle tissue of freshwater fish species and, additionally, in sediments collected from three sampling sites of the Vistula River in the vicinity of Cracow. The determinations of HCH isomers, HCB, DDTs (p,p'-DDE, p,p'-DDD, o,p'-DDT and p,p'-DDT), and six indicator PCB congeners (28, 52, 101, 138, 153, and 180) were carried out in 52 fish samples and 35 sediments samples using capillary gas chromatography. The mean concentration of DDTs in fish was 281 µg/kg wet weight (11.8-1921 µg/kg) and PCBs 83 µg/kg wet weight (10.5-790 µg/kg). The highest levels of contaminants were detected in the muscles of bream. The high levels of DDT and its metabolites, exceeding the PEL values (probable effect levels) were also detected in sediments (mean 270 µg/kg dry weight, range 12.9-927 µg/kg). In fish and sediments from Cracow and downstream from Cracow the levels of DDTs were higher than upstream of the Vistula River. The levels of contaminants remain of concern due to the potential risk to fish consumers and the ecological risk they pose, and indicate a need for a continuous monitoring.
The paper presents the results of monitoring of PCB residues in food of animal origin for the 12 year period of 1997-2008. The residue control plan included analysis of PCB congeners IUPAC No 28, 52, 101, 118, 138, 153 and 180 in a variety of food samples. The residue control program exists in accordance with Council Directive 96/23/EC and legislation of the Ministry of Agriculture and Rural Development. The residue examinations are performed by the National Veterinary Research Institute in Puławy (National Reference Laboratory) and Veterinary Inspection Laboratories (ZHW) located in Białystok, Gdańsk, Katowice, Poznań, Warsaw and Wrocław. The determinations of PCB congeners were conducted using capillary gas chromatography with electron capture detection. Over the period of 12 years residues of PCB congeners were determined in 19 767 samples. The examinations involved the adipose tissue of pigs, cattle, sheep, horses, game (wild boar, roe deer, and deer), chickens, geese, turkeys, ducks and rabbits, farmed fish muscles, cow milk, eggs, honey and import food (mainly marine fish). More than 35% of the samples were found to contain low concentrations of PCBs. In swine and poultry tissues the lowest frequency of PCB residues has been noted. The following highly chlorinated congeners were most frequently detected: PCB 153, PCB 138 and PCB 180. The mean concentrations of indicator PCB congeners were higher in fish and game animals then in other animal species. Generally the levels of PCB congeners were several times lower in comparison to the permitted maximum residue limits in other countries. The regular testing within the national residue control program indicates that Polish food of animal origin contains low levels of these contaminants and is safe for consumers.
Przedstawiono wyniki badań pozostałości pestycydów chloroorganicznych i polichlorowanych bifenyli (PCB) w serach twarogowych i serach twardych dojrzewających pobranych z terenu całego kraju. Potwierdzono opinię o niskim skażeniu chlorowanymi węglowodorami aromatycznymi mleka i przetworów mleczarskich w Polsce.
The paper presents the results of monitoring pesticide residues in food of animal origin for the 10-year-period of 1997 – 2006. The control plan included the analysis of organochlorine pesticides, organophosphorous compounds, pyrethroids, and carbamates in a variety of food samples: fat, muscle and liver from different animal species, milk, eggs and honey. The residue program exists in accordance with Council Directive 96/23/EC and legislation of the Ministry of Agriculture and Rural Development. The residue examinations are performed by the National Veterinary Research Institute in Puławy (National Reference Laboratory) and Regional Veterinary Inspection Laboratories (ZHW) located in Białystok, Gdańsk, Katowice, Poznań, Warsaw and Wrocław. Over the period of 10 years more than 24 500 samples were tested for pesticide residues in all food commodities and only a few samples were non-compliant. The occurrence of organochlorine pesticides was recorded quite frequently, although their concentrations were comparatively low, even several times lower in comparison to the permitted maximum residue levels (MRL). The residues of other groups of pesticides were detected in none of the tested samples. Regular testing within the national residue control program indicates that Polish food of animal origin contains low levels of these contaminants and is safe for consumers.
In 1992 fat samples were taken from 378 hens and from 432 intensive rearing hens; the samples originated from 49 districts of Poland. The levels of organochlorine pesticides and polychlorinated biphenyls (PCBs) were determined by capillary gas chromatography. DDT and metabolites were recorded in all the samples under study. Significantly higher concentrations of S-DDT (x-0.561 mg/kg were found in fat of village hens compared with those obtained from intensive rearing hens (x-195 mg/kg). In both groups of poultry the maximum residue limit of pesticides was exceeded in 12.2% and 3.9% of the samples, respectively. The concentrations of S-DDT in hens were several times higher than the levels of the contaminants in fat of other food of animal origin. PCBs were found in more than 90% of poultry samples and the mean concentration was 0.056 mg/kg for village hens and 0.032 mg/kg for the other group of hens. Other organochlorine pesticides were found in low levels and only in some samples.
Ten lactating healthy cows received single oral doses of Fenbesan (7,6 mg kg⁻¹ b.w. of fenbendazole). Blood samples were collected at 0, 2, 4, 8, 12, 24, 36, 48, 60, 72, 84, 96, 108 and 120 h. Milk samples were taken twice daily from day 0 to 6 after drug administration. Fenbendazole (FBZ), oxfendazole (OXZ) and FBZ sulfone were analysed by HPLC with UV detection. The detection limit was 0,01 µg ml⁻¹ of FBZ and 0,005 µg ml⁻¹ of OXZ and FBZ-sulfone. The highest residues of FBZ, expressed as the sum of parent drug and metabolites were found after 24 and 36 h levels of 0,077 ± 0,01 µg ml⁻¹ and 0,114 ± 0,03 µg ml⁻¹ in milk and plasma respectively. The data show that the parent drug was present in measured quantities in plasma samples collected 8, 12 and 24 h after drug administration (Cmax 0,028 ± 0,008 µg ml⁻¹, Tmax 17,6 ± 0,4 h). In milk, FBZ was detected only 24 h after treatment (0,014 ± 0,006 µg ml⁻¹). This proves that metabolites (OXZ and FBZ-sulfone) dominate in milk and plasma residues. The total residues of FBZ in milk and plasma were below the detection limit by day 5 following a single oral administration of the drug.
A method for simultaneous determination of 13 organophosphorus pesticide residues in milk samples has been developed and validated. The method is based on the extraction of the sample with acetone and petroleum ether, cleanup by gel permeation chromatography, and solid phase extraction, and determination by gas chromatography with flame photometric detection. The recovery, investigated by analysing blank milk samples spiked with azinphos, chlorfenvinphos, chlorpyrifos, chlorpyrifos-methyl, diazinon, fenitrothion, methacrifos, methidathion, parathion-methyl, pyrazophos, and triazophos at concentrations of 10, 20, and 30 µg/kg, and with parathion and pirimiphos-methyl at concentrations of 25, 50, and 75 µg/kg, ranged from 73.1% to 106.2%. Performance characteristics, such as repeatability and within-laboratory reproducibility expressed as coefficient of variation were less than 20%. Measurement uncertainty was lower than 22% for all validated organophosphorus pesticides. The limits of quantification were 10 µg/kg for all compounds and allowed determination of residues at, or even below, the maximum residue limits set by the European Union. The satisfactory z-score results of international proficiency tests confirm good accuracy, reproducibility, and reliability of the developed method.
Przedstawiono wyniki badań pozostałości pestycydów chloroorganicznych i polichlorowanych bifenyli ( PCB) w jajach kur przyzagrodowych i fermowych pobranych z terenu całego kraju. Oznaczone stężenia porównano z wynikami prac wcześniejszych.
Przedstawiono wyniki badań pozostałości pestycydów chloroorganicznych i polichlorowanych bifenyli (PCB) w mleku krowim z terenu całego kraju. Oznaczone stężenia porównano z wynikami prac wcześniejszych.
A method for simultaneous determination of residues of six organophosphorus pesticides in animal liver samples has been developed and validated. The method is based on the extraction of organophosphorus pesticides with a mixture of acetone-petroleum ether, clean up on a gel permeation chromatography, further clean up on a small silica gel column, and finally determination by gas chromatographx with flame photometric detection. The recovery, investigated by analysing blank liver samples spiked with chlorpyrifos-methyl, chlorpyrifos, diazinon, parathion, and pirimiphos-methyl at levels of 5, 25, 50, and 75 µg/kg, and with chlorfenvinphos at levels of 5, 10, and 15 µg/kg, ranged from 75.6% to 107.5%. Performance characteristics, such as repeatability and within-laboratory reproducibility, expressed as coefficient of variation, were less than 20%, and uncertainty <21%. Linearity ranged between 5 and 1,000 ng/mL. The limits of quantification were 5 µg/kg for all compounds and allowed determination of residues below the MRLs set by the European Union. The satisfacton z-score results of international proficiency tests confirmed good accuracy, reproducibility, and reliability of the developed method.
The method for simultaneous determination of residues of seven pyrethroids (bifenthrin, cyfluthrin, lambda-cyhalothrin, cypermethrin, deltamethrin, fenvalerate and permethrin) in animal meat samples has been developed and validated. The method is based on the extraction of pyrethroid residues with mixture of acetone-petroleum ether, freezing step, clean-up on a Florisil column, and finally determination by capillary gas chromatography with electron capture detection (GC-ECD). The analytical process was validated by the analysis of blank meat samples spiked at levels of 10, 20, and 50 µg/kg. Performance characteristics, such as linearity, detection limit (LOD), quantification limit (LOQ), precision, and recovery were determined. The method was efficient with recoveries for all pyrethroids (except deltamethrin) > 80%, repeatability CV < 6%, reproducibility CV < 16%, LOQ 10 µg/kg, and uncertainty < 21%. In 2006 - 2009, the proposed method was applied to the analysis of the pyrethroid residues in 687 meat samples, mainly from poultry, pigs, and ruminants. No residues of pyrethroids were detected in any of these samples.
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