In sub-Saharan Africa, urban and peri-urban food production has been identified as an important resource for meeting the challenges of rapidly growing cities, and the positive aspects of such production have been well documented in the literature. This paper examines some of the health and environmental concerns associated with urban and peri-urban agriculture (UPA). Empirical evidence from the city of Kano in northern Nigeria suggests that there is currently much reason for concern as industrial and domestic toxins are reaching dangerously high levels. As soils and water channels become increasingly polluted, the sustainability of urban and peri-urban food production is questioned. Since the health implications of long-term exposure to toxins are unclear, it is suggested that coordinated longitudinal research involving urban planners, agricultural scientists and health specialists is urgently needed. In addition, it remains crucial that government and institutional actors effectively monitor and enforce both environmental and zoning by-laws, if the health and environmental constraints of UPA are to be overcome, and the future sustainability of production is to be assured. Copyright (C) 2003 John Wiley Sons, Ltd.