Food safety considerations of urban agroforestry systems grown in contaminated environments

Urban Farm DB summary

This review assesses the capacity of woody species (trees and shrubs) used in urban food forests to accumulate polycyclic aromatic hydrocarbons (PAHs), heavy metals (HMs), and metalloids, given limited existing literature on food-safety risk in urban fruit- and nut-producing trees compared with annual crops. General trends identified were (a) lower risk of HM and PAH accumulation in woody species than in vegetables, and (b) less accumulation in the fruit of woody species than in other parts of the same species. However, these trends are not always consistent, and accumulation depends on factors such as the concentration of a given contaminant in the environment, contaminant type, and species or variety. The review states there is a critical need for more research on the safety of growing edible fruits and nuts on trees and shrubs in contaminated urban environments.