Title : Development of novel extraction method for analysis of pesticide residues from human body fluids – Forensic toxicology viewpoint
Fatal pesticide poisoning is common since pesticides are inexpensive, easy to obtain, and widely available. Hence, identification of pesticides in human biological samples such as serum, blood, urine, and saliva is extremely crucial in homicidal and criminal investigations. One of the significant challenges faced by forensic toxicologists is the lack of efficient extraction methods that will help identify and quantify the level of pesticides in biological fluids. An analytical method adopted in toxicological laboratories must produce reliable and accurate results with consistency. To increase laboratory throughput, a complete toxicological analysis workflow system must be developed, which would be extremely useful for forensic toxicologists. Traditional sample preparation techniques are based on SPE or LLE, which are labor-intensive, time-consuming, and often require skilled laboratory personnel for work execution. QuEChERS is a well-known pesticide extraction method in food samples, but its applicability in human biological matrices has been investigated. Hence, a modified QuEChERS method was developed and validated as per SANTE guidelines. The technique relies on sample preparation using a modified QuEChERS d-SPE extraction, followed by UHPLC-QTOF/MS and GC-MS/MS analysis. Good accuracy, specificity, and precision were obtained for the developed method. The extraction method is simple and efficient for simultaneous pre-treatment of human biological matrices. Therefore, this quantitative methodology of using QuEChERS extraction can be regarded as effective for determining pesticide residues and can be employed by a forensic toxicologist in cases related to suspected pesticide poisoning.
Audience Take Away:
- When criminal case involving the use of pesticides is reported, a substantial amount of blood, serum, or urine must be collected for toxicological testing. The developed method is easy, efficient and robust and requires less amount of sample for analysis. Hence, it can be applied for analysis of wide spectrum of pesticides residues in human biological fluids such as urine, blood and serum. The developed research can be further extended to include different target substance such as drugs and urinary metabolites.