GC-MS/MS analysis of chlorpyrifos in forensic samples with varied survival time

Organophosphorus pesticides are extensively used in the agricultural sector to kill insects, worms, and other pests. Many people may be poisoned by chlorpyrifos either accidentally or intentionally, including accidental, suicidal, and homicidal poisoning cases in India. The effect of chlorpyrifos on human health depends on factors such as the time, amount and frequency of exposure, the individual's health, and certain environmental conditions. The main objective of this investigation is to identify the post-mortem biological sample that shows the longest detection window, enabling precise chlorpyrifos detection in cases of acute poisoning with varying survival durations. Our research focuses on the detection and distribution of chlorpyrifos in cases of acute poisoning using a simple liquid-liquid extraction and GC-MS/MS analysis. We validated the method, which proved to be effective and reliable. Upon examining various organs, we detected the presence of chlorpyrifos in the stomach tissue, liver tissue, kidney tissue, and blood samples of individuals who consumed chlorpyrifos and passed away immediately, as well as in those who survived for the first 3 days following ingestion. Analysing urine, blood, and liver tissue from individuals who survived for 3 days provided more precise results compared to stomach tissue. Additionally, urine samples played a crucial role in detecting chlorpyrifos in individuals who survived for 4 and 5 days. A blood sample is the most suitable post-mortem biological sample for detecting chlorpyrifos in individuals who survived for a duration of 2 to 4 days. This finding highlights the significance of analysing urine as a valuable sample type, particularly in determining the presence of chlorpyrifos in cases where individuals have survived for a long period of time before their demise. The experimental data and information provided in this study will serve as a valuable resource for forensic toxicologists.