AbstractThe five most important naturally occurring mycotoxins in human foods and animal feeds are aflatoxin, ochratoxin, deoxynivalenol, zearalenone and fumonisin. Risk assessment is used to manage the risk from mycotoxins to protect human and animal health. Conventional risk assessment has two major components, i.e., exposure assessment and hazard assessment, which data are used to establish Maximum Tolerated Levels (MTLs). Most countries have established MTLs for total aflatoxins ranging from 4-20 ng/g. The US Food and Drug Administration (FDA) has proposed MTLs for total fumonisins of 4 µg/g in whole maize and 2 ng/g in maize products for human consumption. The MTLs proposed by developed countries apply to commodities that they import and to foodstuffs consumed within their borders, but not to agricultural products that they export. Thus conventional risk assessment has helped manage the risk from mycotoxins in developed countries but has not helped in developing countries that import foodstuffs (or receive food aid). The situation with fumonisins in maize is complicated further by large differences in maize consumption by different populations, e.g., from ∼5 g/person/day in Europe to ∼500 g/person/day in rural Africa. The differences in maize intake have a marked effect on the Probable Daily Intake (PDI) of fumonisins by different populations. Subsistence farmers in Africa who consume homegrown maize have the highest maize intakes and also consume maize with the highest levels of fumonisin contamination. Conventional risk assessment has not been of value to them and leaves the people who are at the highest risk for mycotoxin exposure the least protected.