A multi-toxin profile of cereals from diverse agro-ecological zones in Kenya

Kenya has been the epicentre of aflatoxin outbreaks with significant morbidity and mortality. Chronic exposure to fungal metabolites is a risk factor for cancer. Fumonisins have been associated with high incidence of oesophageal cancer. We determined the levels of; aflatoxin levels, fumonisin, ochratoxin, zearalenone, and deoxynivalenol in cereals from Eastern, Coastal, Nairobi, and Western Kenya. A total, 549 Cereals (maize and maize products, nuts, beans, rice, and mixed cereals) were analysed using Envirologix Quick ToxTM Kits and QC through HPLC fluorescence detection. Maize (68.1%), beans (5.5%), wheat (3.3%), rice (4.0%), mixed cereals (3.8%), and other nuts (11.0%) were contaminated with aflatoxin. The average aflatoxin contamination was 38.5% with 27.1% considered unfit for human consumption (Aflatoxin >20ppb). Kwale (91%) reported the highest rate of aflatoxin contamination followed by Loitokitok (61%), Nairobi (47%), Nakuru (16%) Kisumu (25%), Eldoret (46.0%), Kitale (38.5%), Mombasa (18%) and Eastern (32%). For fumonisin, Eastern reported the highest levels of fumonisins (63.0%), followed by Nairobi (29.4%), Kitale (15.4%), Kisumu (12.5%), Eldoret (7.7%) and Nakuru (4%). Over 50% of the nuts in Eastern, Kitale, Eldoret, and Nairobi was positive for aflatoxin. There is widespread aflatoxin and fumonisin contamination in cereals with maize and nuts being the most mycotoxic, while Eastern, Nairobi, and Kwale were the ‘hot’ spots. Risk of significant mycotoxin exposure through contaminated stable food in Kenya exist with far reaching health consequences such as cancer. This calls for measures to protect the public from chronic mycotoxin exposure.