Bio-monitoring of mycotoxin exposure in Cameroon using a urinary multi-biomarker approach
Wilfred A Abia1, Benedikt Warth, Michael Sulyok
1Laboratory of Pharmacology and Toxicology, Department of Biochemistry, Faculty of Science, University of Yaounde I, P.O. Box 812, Yaounde, Cameroon; Center for Analytical Chemistry, Department for Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Str. 20, A-3430 Tulln, Austria; Department of Food Technology, Faculty of Science, University of Johannesburg, P.O. Box 17011, Doornfontein Campus, 2028 Gauteng, South Africa.
Abstract:
Bio-monitoring of human exposure to mycotoxin has mostly been limited to a few individually measured mycotoxin biomarkers. This study aimed to determine the frequency and level of exposure to multiple mycotoxins in human urine from Cameroonian adults. 175 Urine samples (83% from HIV-positive individuals) and food frequency questionnaire responses were collected from consenting Cameroonians, and analyzed for 15 mycotoxins and relevant metabolites using LC-ESI-MS/MS. In total, eleven analytes were detected individually or in combinations in 110/175 (63%) samples including the biomarkers aflatoxin M1, fumonisin B1, ochratoxin A and total deoxynivalenol. Additionally, important mycotoxins and metabolites thereof, such as fumonisin B2, nivalenol and zearalenone, were determined, some for the first time in urine following dietary exposures. Multi-mycotoxin contamination was common with one HIV-positive individual exposed to five mycotoxins, a severe case of co-exposure that has never been reported in adults before. For the first time in Africa or elsewhere, this study quantified eleven mycotoxin biomarkers and bio-measures in urine from adults. For several mycotoxins estimates indicate that the tolerable daily intake is being exceeded in this study population. Given that many mycotoxins adversely affect the immune system, future studies will examine whether combinations of mycotoxins negatively impact Cameroonian population particularly immune-suppressed individuals.
