Toxicokinetic analysis of commonly used pesticides using data on acute poisoning cases from Hyderabad, South India. (April 2021)

• Record Type: Journal Article
• Authors: Sinha, Sukesh Narayan; Kumar, Kumpati Rajesh; Ungarala, Ramakrishna; Kumar, Dileshwar; Deshpande, Abhijeet; Vasudev, K.; Boiroju, Naveen Kumar; Singh, Amrisha; Naik, R. Pandu; Pokharakar, Sunil
• Is Part Of: Chemosphere. Volume 268(2021)
• Publication Date: 2021-04
• Subjects: Organophosphorus pesticides -- Toxicokinetics -- Poisoning cases -- Acetylcholinesterase (AChE) -- Elimination phase; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2020.129488
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Organophosphorus pesticides (OPs) interfere with the activity of acetylcholinesterase (AChE), a vital enzyme that regulates the functioning of the nervous system, resulting in acetylcholine (Ach) accumulation at the synapses and myoneural junctions. It remains unknown whether the commonly used OPs in South India also interfere with the AChE activity and their toxicokinetics in humans remains poorly understood. We collected peripheral blood samples from OP-associated suicide cases (hospitalised) and analysed the pesticide concentration and AChE activity, and the toxicokinetics of six commonly used pesticides. LC-MS/MS was used for the estimation of pesticide concentration. Based on a comparison of six pesticide kinetic profiles and toxicokinetic parameters, we concluded that chlorpyrifos ingestion resulted in the highest concentration of chlopyrifos among the identified pesticides, followed by acephate, triazophos, propanil, while dimethoate exhibited the lowest concentration. Based on a time-course analysis, we observed a faster elimination phase for monocrotophos and dimethoate. We observed that there was a significant decrease in the mean concentration of monocrotophos (64 ng/mL) ( P = 0.015), while the mean value of AChE (1.08 unit/mL) increased over time. While monocrotophos and dimethoate elimination phases were remarkable in human subjects, the other pesticides did notdemonstrate similar elimination phases owing to their low rate of metabolism and high stability. Graphical abstract: Image 1 Highlights: Pesticide concentration of 6 commonly used pesticides was analysed in blood of suicide cases & correlated with AChE levels. Chlorpyrifos shows the highest exposure, while Dimethoate shows the least exposure. Mean Concentration of Monocrotophos decreased significantly, while mean AChE concentration increased across the time. Elimination phase was observed only in case of Monocrotophos and Dimethoate of the 6 pesticides analysed. Chloropyrifos, Dichlorovos, Triazophos, and Propanil did not reach the elimination phase till the time point analysed.