ABSTRACT
The effects of processing to produce various types of tea or infusion on the levels of pesticide residues in tea were investigated for three insecticides (chlorfenapyr, pyrimiphos-methyl, and clothianidin). Tea plants were sprayed with one of the three pesticides and cultivated under cover. The levels of pesticide residues in tea decreased after processing according to the time and temperature of heating, as well as fermentation. Although significant differences were not observed among the three pesticides in the ratio of decreased of pesticide concentration after processing to green tea, clothianidin, which is a neonicotinoid insecticide and has a lower log Pow value, tended to be transferred more than the other two insecticides into infusions. However, no significant difference in the ratios of clothianidin transferred to infusions was observed among green tea with three different leaf sizes.
Subject(s)
Camellia sinensis/chemistry , Food Contamination/analysis , Food Handling , Guanidines/analysis , Organothiophosphorus Compounds/analysis , Pesticide Residues/analysis , Pyrethrins/analysis , Tea/chemistry , Thiazoles/analysis , Chromatography, High Pressure Liquid , Fermentation , Neonicotinoids , Tandem Mass Spectrometry , Temperature , TimeABSTRACT
A simple clean-up method was developed for the simultaneous determination of pesticide residues in livestock products by GC-MS/MS. The pesticide residues were extracted with acetonitrile-ethanol (1 : 1), and matrix components such as adipose were effectively eliminated by a combination of refrigerated centrifugation, dispersive solid-phase extraction, and multifunctional column chromatography. In this method, samples are treated quickly and easily without the need for gel-permeation chromatography. Among 131 pesticides tested, 115 showed recovery within the range from 70 to 120%, with relative standard deviations of less than 15%. The quantification limits for the 115 pesticides in livestock products were 0.001 to 0.01 µg/g.
Subject(s)
Food Analysis/methods , Gas Chromatography-Mass Spectrometry/methods , Meat Products/analysis , Pesticide Residues/analysis , Pesticide Residues/isolation & purification , Solid Phase Extraction/methods , Tandem Mass Spectrometry/methods , Animals , Cattle , Chickens , SwineABSTRACT
Development of rapid and high accuracy analysis, and tightening of regulations for veterinary drugs are required because many examples of detection of veterinary drugs in many kinds of processed food have been reported. In this study, we constructed an improved method for simultaneous determination of veterinary drugs, based on the glass bead homogenization method with EDTA-2Na and batch purification for QuEChERS analysis. Our extraction procedure is suitable for handling multiple samples quickly and easily. Furthermore, our improved extraction solvent allowed simultaneous determination of tetracyclines in processed food. In a test of 69 veterinary drugs, recovery of over 60 ranged from 70 to 120%, with a coefficient of variation of less than 25% and with quantification limits of 0.01 µg/g (S/N≥10 ). This improved method is expected to be useful for quick simultaneous determination of multiple residues.
Subject(s)
Drug Residues/analysis , Food Analysis/methods , Veterinary Drugs/analysis , Food Handling , Tetracyclines/analysisABSTRACT
It is considered to be difficult to detect tetracycline antibiotics in all-at-once simultaneous analysis with other drugs by liquid chromatography with tandem mass spectrometry, because tetracycline antibiotics chelate with bivalent metal ions such as calcium in samples. Therefore, we studied simultaneous determination of tetracycline antibiotics after removal of calcium with disodium ethylenediaminotetraacetate (EDTA-2Na). Tetracycline antibiotics could be assayed in all-at-once analysis by adding EDTA-2Na during the extraction procedure. It was possible to determine 65 veterinary drugs in milk, 70 in yogurt, 59 in whipped cream, 67 in cheese and 60 in ice cream. Recovery ranged from 70 to 120%, with a coefficient of variation of less than 25% and with a quantification limit of 0.01 microg/g (S/N>or=10).
