Analytical challenges related to the measurement of chlorothalonil in serum in the perspective of human biomonitoring studies.

Autor: Bichon E; LABERCA, Oniris, INRAE, Nantes, France. Electronic address: emmanuelle.bichon@oniris-nantes.fr., Hillenweck A; UMR 1331 TOXALIM, Université de Toulouse, INRAE, INP-ENVT, INP-EI-PURPAN, UPS 31027 Toulouse, France., Marais B; LABERCA, Oniris, INRAE, Nantes, France., Guiffard I; LABERCA, Oniris, INRAE, Nantes, France., Le Bizec B; LABERCA, Oniris, INRAE, Nantes, France., Zalko D; UMR 1331 TOXALIM, Université de Toulouse, INRAE, INP-ENVT, INP-EI-PURPAN, UPS 31027 Toulouse, France., Marchand P; LABERCA, Oniris, INRAE, Nantes, France.
Jazyk: angličtina
Zdroj: Talanta [Talanta] 2024 Sep 01; Vol. 277, pp. 126408. Date of Electronic Publication: 2024 Jun 11.
DOI: 10.1016/j.talanta.2024.126408
Abstrakt: Chlorothalonil (CTN) is a popular fungicide widely used in the world. However, its determination in serum samples is highly challenging, preventing a reliable investigation of human CTN internal exposure. We first investigated CTN's behaviour all along this analytical process on spiked serum samples. We used a radiolabelled 14 C-CTN standard to monitor CTN in spiked serum samples and observed (1) a complete degradation of CTN in deproteinised serum samples after 4 h of contact; (2) a strong interaction between serum proteins and CTN by-products, with only 20 % of the radioactivity found to be extractable after 24 h of contact and (3) a slightly improved stability of CTN in serum following a first step of acidification or EDTA addition to samples. Using liquid chromatography coupled to high resolution mass spectrometry, 4-hydroxy-2,5,6-trichloroisophthalonitrile (HCTN) was identified as the major serum by-product of CTN. A protocol was developed to monitor both extractable CTN and HCTN from serum. This method was implemented on 36 human adult serum samples from the French "Esteban" Cohort. No free CTN was identified in these serum samples. Conversely, HCTN was detected in all samples at concentrations around 15 ± 2 ng mL -1 , corresponding to the extractable fraction of CTN. Thus, HCTN may constitute a relevant biomarker of human internal exposure. Of note, the potential CTN contamination during blood collection could also be a source of HCTN detection in serum samples. Finally, blood sampling in EDTA tubes would seem more appropriate than in dry tubes for any future internal exposure studies on CTN.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier B.V.)
Databáze: MEDLINE
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