Simultaneous quantification of carbamate insecticides in human plasma by liquid chromatography/tandem mass spectrometry

Abstract

Carbofuran (CFN), carbosulfan (CSN) and fenobucarb (FBC) are carbamate pesticides that are widely used in gardening and agriculture for the control of insects. Human poisoning due to occupational or self-poisoning exposures is also reported, so assays are required to quantify the plasma concentration of these insecticides. An LC-MS/MS method was developed and validated for the simultaneous quantification of these three carbamate insecticides in the plasma of patients with acute intentional self-poisoning. Plasma samples were pretreated by acetonitrile for protein precipitation. Chromatography was carried out on a Luna C18(2) analytical column with gradient elution using a mobile phase containing acetonitrile and water with 10mM ammonium acetate. Mass spectrometric analysis was performed by an Applied Biosystems MDS Sciex API 2000 triple quadrupole mass spectrometer coupled with electrospray ionization (ESI) source in the positive ion mode. The total run time was 7 min. The assay was validated over a concentration range from 10 to 1000 ng/ml for CSN and FBC and 20-2000 ng/ml for CFN. The precision and accuracy for both intra- and inter-day determination of all analytes were acceptable (<15%). No significant matrix effect was observed. Stability of compounds was established for short term bench and autosampler storage as well as freeze/thaw cycles. The method was effectively applied to 270 clinical samples from patients with a history of acute intentional carbamate self-poisoning.

Identification and quantification of carbamate pesticides in dried lime tree flowers by means of excitation-emission molecular fluorescence and parallel factor analysis when quenching effect exists

“…The determination of carbamates can be carried out using several techniques, such as highperformance liquid chromatography (HPLC) with fluorescence detection [19], with diode array detection (DAD) [20], or with UV detection [21]; liquid chromatography with mass spectrometry detection (LC/MS) [22] or with tandem mass spectrometry detection (LC/MS-MS) [23,24]. Thermal instability and polarity of many carbamates have limited the use of gas chromatography for their determination [25].…”

Determination of carbamates in beverages by liquid-liquid extraction with low temperature partitioning and liquid chromatography

“…However, they are potentially toxic to humans, particularly in the context of intentional self-poisoning. 1,2 Carbamates are found as commercialized products for agricultural practices and some compounds of this group, with their respective commercial names are: carbaryl (Sevin ® ), aldicarb (Temik ® ) and carbofuran (Furadan ® ). From these, aldicarb stands out as the main target on the list of controlled pesticides of the United States Environmental Protection Agency (EPA) due to its elevated toxicity to mammals.…”

“…Carbofuran was detected in 158 samples at a concentration ranging from 20.7 to 62,200 ng mL -1 . 1 The LD 50 (lethal dose, 50%) for carbofuran 16 that can cause acute toxicity to mammals through cholinesterase inhibition is 2 mg g −1 .…”

“…Carbofuran was detected in 158 samples at a concentration ranging from 20.7 to 62,200 ng mL -1 . 1 The LD 50 (lethal dose, 50%) for carbofuran 16 that can cause acute toxicity to mammals through cholinesterase inhibition is 2 mg g −1 .In Brazil, a retrospective study using data gathered by the Toxicological Information Centers and emergency hospital have shown the "chumbinho" (an illegal rodenticide in which the main ingredient is carbamate insecticide aldicarb) was involved in most cases of poisoning. 9,15 These compounds are commonly found in foods and beverages in cases of accidental or intentional intoxication.…”

“…17,[30][31][32] The identification of these compounds in different matrices as well as their quantification are of interest in the criminal field since the number of human 3,17,[33][34][35][36] 53 or supercritical fluid extraction 54 followed by gas 20,50,[55][56][57][58][59][60] or liquid chromatography. 1,19,48,49,52,53,[61][62][63][64][65][66][67][68][69][70] The low volatility and the thermolability of these compounds and the high polarities of the transformation products obviously favor the use of column liquid chromatography (LC) as the separation technique.Due to the low detection levels required by regulatory agencies, efficient sample preparation and trace-level detection are important aspects in an analytical method. The extraction and cleanup steps are sometimes carried out simultaneously using techniques such as solid-phase extraction (SPE) and solvent extraction with low temperature partitioning (SE-LTP).…”