Dataset Information

Improving the Screening Analysis of Pesticide Metabolites in Human Biomonitoring by Combining High-Throughput In Vitro Incubation and Automated LC-HRMS Data Processing

ABSTRACT: There is a current need to monitor human exposure to a large number of pesticides and other chemicals of emerging concern (CECs). This requires screening analysis with high confidence for these compounds and their metabolites in complex matrices, which is hampered by the fact that no reference standards are available for most metabolites. We address this challenge by a high-throughput workflow based on incubation of pesticides (or other CECs) with human liver S9, followed by solid-phase extraction, liquid chromatography-high-resolution mass spectrometry (LC-HRMS) analysis, and automated data processing to generate a database (retention time, precursor m/z, and MS² spectral library) for the annotation in human samples. The metabolite prioritization consists of statistical comparisons and mass defect and m/z range filtering to obtain a subset of probable phase I metabolites, for which molecular formulas and likely metabolic transformation are retrieved. We tested the workflow on 22 pesticides, for which we could determine 91 metabolite molecular formulas which are only partly covered by the literature and/or predicted by in silico metabolization. Our workflow allows for an efficient generation of metabolite reference information, which can be used directly for annotating LC-HRMS data from human samples. A full structure elucidation of individual metabolites can be limited to those being actually present in human samples.

INSTRUMENT(S): Liquid Chromatography MS - negative - reverse phase, Liquid Chromatography MS - positive - reverse phase

SUBMITTER: Carolin Huber

PROVIDER: MTBLS2402 | MetaboLights | 2022-01-17

REPOSITORIES: MetaboLights

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			Action	DRS
	MTBLS2402	Other
	FILES	Other
	a_MTBLS2402_LC-MS_negative_reverse-phase_metabolite_profiling.txt	Txt
	a_MTBLS2402_LC-MS_positive_reverse-phase_metabolite_profiling.txt	Txt
	files-all.json	Other

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Improving the Screening Analysis of Pesticide Metabolites in Human Biomonitoring by Combining High-Throughput <i>In Vitro</i> Incubation and Automated LC-HRMS Data Processing.

Huber Carolin C Müller Erik E Schulze Tobias T Brack Werner W Krauss Martin M

Analytical chemistry 20210623 26

There is a current need to monitor human exposure to a large number of pesticides and other chemicals of emerging concern (CECs). This requires screening analysis with high confidence for these compounds and their metabolites in complex matrices, which is hampered by the fact that no reference standards are available for most metabolites. We address this challenge by a high-throughput workflow based on incubation of pesticides (or other CECs) with human liver S9, followed by solid-phase extracti ...[more]

PMID: 34161736

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