Association between Tortilla Consumption and Human Urinary Fumonisin B1 Levels in a Mexican Population

doi:10.1158/1055-9965.EPI-07-2534

Association between Tortilla Consumption and Human Urinary Fumonisin B1 Levels in a Mexican Population

¹Molecular Epidemiology Unit, Centre for Epidemiology and Biostatistics, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds; ²CRUK Clinical Centre, St. James's University Hospital, Leeds, United Kingdom; ³Instituto Nacional de Salud Pública, Morelos, Mexico; and ⁴Institute for Food Chemistry, University of Münster, Münster, Germany

Requests for reprints:
Christopher P. Wild, Molecular Epidemiology Unit, Centre for Epidemiology and Biostatistics, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT, United Kingdom. Phone: 44-113-3436602; Fax: 44-113-3436603. E-mail: c.p.wild{at}leeds.ac.uk

Abstract

Fumonisins are mycotoxins produced by Fusarium spp. and commonly contaminate maize and maize products worldwide. Fumonisins are rodent carcinogens and have been associated with human esophageal cancer. However, the lack of a valid exposure biomarker has hindered both the assessment of human exposure and the evaluation of disease risk. A sensitive liquid chromatography-mass spectrometry method to measure urinary fumonisin B1 (FB1) following extraction on Oasis MAX cartridges was established and applied to urine samples from women in a cohort recruited in Morelos County, Mexico. Urinary FB1 was compared with dietary information on tortilla consumption. FB1 recovery in spiked samples averaged 94% as judged by deuterium-labeled FB1 internal standard. Urinary FB1 was determined in 75 samples from women selected based on low, medium, or high consumption of maize-based tortillas. The geometric mean (95% confidence interval) of urinary FB1 was 35.0 (18.8-65.2), 63.1 (36.8-108.2), and 147.4 (87.6-248.0) pg/mL and the frequency of samples above the detection limit (set at 20 pg FB1/mL urine) was 45%, 80%, and 96% for the low, medium, and high groups, respectively. Women with high intake had a 3-fold higher average FB1 levels compared with the “low intake” group (F = 7.3; P = 0.0015). Urinary FB1 was correlated with maize intake (P_trend = 0.001); the correlation remained significant after adjusting for age, education, and place of residence. This study suggests that measurement of urinary FB1 is sufficiently sensitive for fumonisin exposure assessment in human populations and could be a valuable tool in investigating the associated health effects of exposure. (Cancer Epidemiol Biomarkers Prev 2008;17(3):688–94)

Footnotes

Grant support: National Institute of Environmental Health Sciences grant ES06052 (University of Leeds). The assembly and follow-up of the Mexican cohort was supported by Consejo Nacional de Ciencia y Tecnología de México grant CONACyT 31034-M; 41708; 13915.
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
- Accepted December 14, 2007.
- Received September 7, 2007.
- Revision received December 10, 2007.