Occurrence and risk assessment of mycotoxins in subsistence farmed maize from Zimbabwe M. Hove a, b, * , M. De Boevre a , C. Lachat c, d , L. Jacxsens c , L.K. Nyanga b , S. De Saeger a a Laboratory of Food Analysis, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium b Institute of Food Nutrition and Family Sciences, University of Zimbabwe, P.O. Box MP167, Mount Pleasant, Harare, Zimbabwe c Department of Food Safety and Food Quality, Ghent University, Coupure Links 653 Bl. B, 9000, Ghent, Belgium d Nutrition and Child Health Unit, Institute of Tropical Medicine, Nationalestraat 155, 2000, Antwerp, Belgium article info Article history: Received 26 February 2016 Received in revised form 20 April 2016 Accepted 21 April 2016 Available online 23 April 2016 Keywords: Mycotoxins maize exposure assessment fumonisins Zimbabwe abstract Maize is the staple food of Zimbabweans and is consumed daily in the majority of households, partic- ularly subsistence farming households. The objectives of this study were first, to determine the occur- rence of mycotoxins in maize produced and consumed by subsistence farmers in Zimbabwe and second, to determine mycotoxin exposure through maize consumption and subsequently the human health risk. A total of 95 maize meal samples were collected from the household stores of randomly selected sub- sistence farming households. Maize intake data and agronomic practices of these households were investigated A multi-mycotoxin LC-MS/MS method was used to analyze and quantify mycotoxin contamination in the maize samples. Mycotoxin contamination was compared across agro-ecological zones in order to determine differences in mycotoxin contamination levels and presented. Of the toxi- cologically relevant mycotoxins, aflatoxin B1 (AFB1), fumonisin B1 (FB1), FB2, deoxynivalenol (DON) and zearalenone (ZEN) were detected in 1, 95, 31, 24 and 15 % of the samples at mean levels of 11, 242,120, 217 and 110 mg/kg respectively. Other mycotoxins detected in the maize were 15-acetyl-deoxynivalenol (15-ADON), nivalenol (NIV), FB3, alternariol-methylether (AME), AFB2, AFG1 and diacetoxyscirpenol (DAS) and the percentage contamination ranged between 1 and 4 % in the maize samples. Contamination of the maize by the mycotoxins was observed at minimum levels below limit of detection for each mycotoxin and maximum levels of 105, 530, 67,108, 3, 4 and 14 mg/kg for 15-ADON, NIV, FB3, AME, AFB2, AFG1 and DAS respectively. The median levels of each mycotoxin were reported below the limit of detection, with the exception of FB1 (median, 146 mg/kg), which was further considered in the exposure and risk assessment. Dietary exposure was derived from combining mean maize intake data and median FB1 contamination. Mean maize intake was estimated to be 26.8, 37.2, 30.1, 15.8 and 15.0 g/kg body- weight (bw)/day for under 5s, children, adolescents, adults and the elderly respectively. Subsequently FB1 exposure from maize was calculated, to be 3.91, 5.40, 4.40, 2.30 and 2.20 mg/kg bw/day for these populations. Exposure to FB1 through maize intake was observed to equate to 196, 272, 220,115 and 110 % of the provisional maximum tolerable daily intake (2 mg/kg bw/day) for under 5s, children, adolescents, adults and the elderly respectively. Subsistence farming communities in Zimbabwe are at risk of high exposure to FB1 and the risk was highest for under 5s, children and adolescents respectively. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction Mycotoxins are small molecular weight chemical substances (Steyn, 1995, Pitt, 2000) classified as secondary metabolites that are toxic in nature and produced by a variety of fungi in a number of plants, crops, fruits and seeds (Richard, 2007). They are often naturally occurring in either free or modified forms (De Boevre et al., 2012). As such they can find their way into the food chain resulting in human exposure either by direct consumption (humans eating contaminated plants, crops, fruits and seeds) or indirectly through ingestion of exposed animals (chicken, pigs or cows, among others). This process triggers acute or chronic effects Abbreviations: LSD, least significant difference; PMTDI, provisional maximum tolerable daily intake. * Corresponding author. E-mail address: Melody.Hove@Ugent.be (M. Hove). Contents lists available at ScienceDirect Food Control journal homepage: www.elsevier.com/locate/foodcont http://dx.doi.org/10.1016/j.foodcont.2016.04.038 0956-7135/© 2016 Elsevier Ltd. All rights reserved. Food Control 69 (2016) 36e44