Heavy Metal Contamination in Food: The Perspective of the Sub-Saharan Informal Food Trade

Abstract

Food safety is often threatened by the intended or unintended introduction of contaminants. Street foods are susceptible to microbial, chemical and physical contaminants. Due to their ubiquitous existence in the environment, heavy metals are among the majority of food material contaminants and they are believed to have carcinogenic properties. Heavy metals have been a source of contamination in the informal food value chain mainly due to their bioaccumulation and existence in voluminous amounts. Several factors account for the rate of contamination and the continued failure to prevent it. Carcinogens such as lead and arsenic are often present in high levels in some vended foodstuffs, and their prolonged ingestion could have injurious effects on consumer health. Heavy metal contamination in street-vended foods sometimes occurs as a result of leaching from poorly designed or old and inadequately cleaned utensils. Moreover, aluminium pots used in cooking may leach aluminium ions, especially when acidic foods such as grains and seafood are cooked.