Multiresidue method for high-performance liquid chromatography determination of carbamate pesticides residues in tea samples

Abstract

A multiresidue method was developed to determine 19 carbamate pesticides in tea samples. Optimizations of different parameters, such as the type of extraction solvents, clean-up cartridges, and elution solvents were carried out. The developed method used acetonitrile as extraction solvent, amino cartridge for adsorbents and acetone-n-hexane as the eluting solution. Nineteen carbamate residues were then analyzed by high-pressure liquid chromatography (HPLC) with fluorescence detector. The present results showed good linearity by correlation coefficients of more than 0.9999 for all analyses. Limits of detection and quantification varied from 0.0005-0.023 mg L(- 1), 0.008-0.077 mg L(- 1), respectively. Recoveries of sixteen carbamate pesticides ranged from 65% to 135% at the spiked level of 0.5, 1.0 and 2.0 mg L(- 1). The relative standard deviations were lower than 20% and coefficient of variations were lower than 15%. The results indicate that the proposed method provides an effective multi and trace level screening determination of carbamate pesticides residues for tea samples.

Analysis of contaminant polycyclic aromatic hydrocarbons in tea products and crude drugs

“…Recently, it has been suggested that certain contaminants in crude drugs and tea products may pose a health threat to herbal product takers. The main contaminants that have been investigated widely and intensively are pesticides [1][2][3][4][5][6][7][8] and heavy metals. 1,[9][10][11][12][13] Thus, the lack of quality control of these herbal products is a problem for their development and application.…”

Application of an optimized modified stir bar with ZnS nanoparticles loaded on activated carbon for preconcentration of carbofuran and propoxur insecticides in water samples and their HPLC determination

“…N-Methylcarbamate pesticides (NMCs) were commercially available in the 1950s and since then, they have been increasingly used in modern agriculture, for example, in the production of potato, cabbage, coffee, citrus and other crops. [1][2][3] Due to their widespread use, carbamate pesticides may enter into environmental water systems through various paths, including soil seepage, spraying, storage and the discharge of wastewater, leading to possible contamination of the environmental water. [4][5][6] Although carbamates are generally highly biodegradable, some are hazardous to the environment and human health because carbamates are central nervous system toxins and strong endocrine disruptors, affecting humans and animals at low doses.…”

Modified QuEChERS method for the analysis of 11 pesticide residues in tea by liquid chromatography–tandem mass spectrometry

“…[7][8][9] It was found that 5 organophosphorus (dimethoate, malathion, methidathion, triazophos, chlorpyrifos) and 6 carbamate (isoprocarb, carbaryl, carbosulfan, carbendazim, propoxur and pirimicarb) pesticides are oen detected in teas. [10][11][12][13][14][15] It is well known that the carbamate pesticides have high water solubility, high polarity and thermal instability. They are difficult to detect by gas chromatography (GC) because these compounds easily decompose to the homologous phenols and amines during the determination process.…”