RESEARCH PAPER Simultaneous determination of multiclass pesticide residues in human plasma using a mini QuEChERS method Anshuman Srivastava 1,2 & Satyajeet Rai 1 & Ashish Kumar Sonker 1,3 & Kajal Karsauliya 1 & Chandra Prabha Pandey 2 & Sheelendra Pratap Singh 1,3,4 Received: 17 January 2017 /Revised: 1 March 2017 /Accepted: 14 March 2017 # Springer-Verlag Berlin Heidelberg 2017 Abstract Blood is one of the most assessable matrices for the determination of pesticide residue exposure in humans. Effective sample preparation/cleanup of biological samples is very important in the development of a sensitive, reproduc- ible, and robust method. In the present study, a simple, cost- effective, and rapid gas chromatography–tandem mass spec- trometry method has been developed and validated for simul- taneous analysis of 31 multiclass (organophosphates, organo- chlorines, and synthetic pyrethroids) pesticide residues in hu- man plasma by means of a mini QuEChERS (quick, easy, cheap, effective, rugged, and safe) method. We have adopted a modified version of the QuEChERS method, which is primar- ily used for pesticide residue analysis in food commodities. The QuEChERS method was optimized by use of different extrac- tion solvents and different amounts and combinations of salts and sorbents (primary–secondary amines and C 18 ) for the dis- persive solid-phase extraction step. The results show that a com- bination of ethyl acetate with 2% acetic acid, magnesium sulfate (0.4 g), and solid-phase extraction for sample cleanup with pri- mary–secondary amines (50 mg) per 1-mL volume of plasma is the most suitable for generating acceptable results with high recoveries for all multiclass pesticides from human plasma. The mean recovery ranged from 74% to 109% for all the analytes. The limit of quantification and limit of detection of the method ranged from 0.12 to 13.53 ng mL -1 and from 0.04 to 4.10 ng mL -1 respectively. The intraday precision and the interday precision of the method were 6% or less and 11% or less respectively. This method would be useful for the analysis of a wide range of pesticides of interest in a small volume of clinical and/or forensic samples to support biomonitoring and toxicological applications. Keywords Quick, easy, cheap, effective, rugged, and safe . Human plasma . Pesticide residue . Gas chromatography– tandem mass spectrometry . Sample cleanup Introduction Pesticides are some of the most important agrochemicals used in agriculture for minimizing farm and postharvest losses of crops and ensuring effective crop production. Injudicious and indiscriminate use of pesticides and lack of use of safety ap- pliances during manufacturing, storage, transportation, and agricultural application increases the threat of exposure of the human population to pesticides. Moreover, imprudent use of pesticides during agricultural applications may result in the occurrence of their residues in agriculture commodities and may lead to dietary exposure of human populations [1–4]. Therefore, it is important to determine the pesticide Anshuman Srivastava and Satyajeet Rai contributed equally to this work The CSIR–Indian Institute of Toxicology Research communication number for the manuscript is 3445. * Sheelendra Pratap Singh sheelendra@iitr.res.in 1 Pesticide Toxicology Laboratory, Regulatory Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vish Vigyan Bhavan 31, Mahatma Gandhi Marg, Lucknow 226001, Uttar Pradesh, India 2 Department of Chemistry, Babu Banarasi Das University, Faizabad Road, Lucknow 226028, Uttar Pradesh, India 3 Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Lucknow, India 4 Analytical Chemistry Laboratory, Regulatory Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vish Vigyan Bhavan 31, Mahatma Gandhi Marg, Lucknow 226001, Uttar Pradesh, India Anal Bioanal Chem DOI 10.1007/s00216-017-0317-7