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Cholinesterase and paraoxonase (PON1) enzyme activities in Mexican–American mothers and children from an agricultural community

Journal of Exposure Science & Environmental Epidemiology volume 22, pages 641–648 (2012)Cite this article

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Abstract

Exposure to organophosphate and carbamate pesticides can lead to neurotoxic effects through inhibition of cholinesterase enzymes. The paraoxonase (PON1) enzyme can detoxify oxon derivatives of some organophosphates. Lower PON1, acetylcholinesterase, and butyrylcholinesterase activities have been reported in newborns relative to adults, suggesting increased susceptibility to organophosphate exposure in young children. We determined PON1, acetylcholinesterase, and butyrylcholinesterase activities in Mexican–American mothers and their 9-year-old children (n=202 pairs) living in an agricultural community. We used Wilcoxon signed-rank tests to compare enzymatic activities among mothers and their children, and analysis of variance to identify factors associated with enzyme activities. Substrate-specific PON1 activities were slightly lower in children than their mothers; however, these differences were only statistically significant for the paraoxon substrate. We observed significantly lower acetylcholinesterase but higher butyrylcholinesterase levels in children compared with their mothers. Mean butyrylcholinesterase levels were strongly associated with child obesity status (body mass index Z scores >95%). We observed highly significant correlations among mother-child pairs for each of the enzymatic activities analyzed; however, PON1 activities did not correlate with acetylcholinesterase or butyrylcholinesterase activities. Our findings suggest that by age 9 years, PON1 activities approach adult levels, and host factors including sex and obesity may affect key enzymes involved in pesticide metabolism.

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Acknowledgements

We gratefully acknowledge the CHAMACOS staff, community partners, and especially the CHAMACOS participants. We thank Justin Dittmeier for assisting with cholinesterase activity measurements. This work was supported by grants from the US Environmental Protection Agency (R826886, R82670901) and the National Institute of Environmental Health Science (R01ESO12503, PO1 ES009605). The contents of this paper are solely the responsibility of the authors and do not necessarily represent the official views of the NIEHS and the EPA.

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  1. Veronica Gonzalez and Karen Huen: First co-authors

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  1. Center for Environmental Research and Children's Health (CERCH), 50 University Hall, School of Public Health, University of California, Berkeley, California, USA

    Veronica Gonzalez, Karen Huen, Subha Venkat, Kelly Pratt, Pin Xiang, Kim G Harley, Katherine Kogut, Celina M Trujillo, Asa Bradman, Brenda Eskenazi & Nina T Holland

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Gonzalez, V., Huen, K., Venkat, S. et al. Cholinesterase and paraoxonase (PON1) enzyme activities in Mexican–American mothers and children from an agricultural community. J Expo Sci Environ Epidemiol 22, 641–648 (2012). https://doi.org/10.1038/jes.2012.61

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