Urban agriculture is gaining importance as a social means to produce food locally. However cities are well-known sources of pollution, which may contaminate urban crops. There is actually little knowledge on the degree of contamination of urban vegetables. Agronomists Vittori Antisari et al. analysed the heavy metal content of vegetables in the city of Bologna, Italy. They found that the most contaminated vegetables grew near roads, which is explained by traffic pollution.
Urban agriculture will increase because more than 50% of the world population actually lives in cities, and local production is both socially and economically more efficient. Agronomists Eigenbrod and Gruda reviewed various urban agriculture systems. They found that growing vegetables in cities is particularly beneficial.
Urban farming is a potential way to reduce poverty and improve food safety. In sub-Saharan African cities, urban farmers have intensified vegetable production to meet the demand from inhabitants. A such rapid change may induce unintended hazards. A study of tomato production in urban gardens in Benin by Perrin et al. indeed revealed poor practices and high risks for health and the environment.