Urban Gardening—How Safe Is It?

Abstract

Urban gardening has become more and more popular in recent years, as people might prefer to grow their own vegetables from controlled sources. In addition, community building also plays a key role. However, air pollution in settlements is a serious hazard affecting the quality of home-grown vegetables. During the vegetation period, traffic is the main factor generating atmospheric particulate matter. These particles will, in turn, bind to potentially toxic compounds, of which heavy metals and polycyclic aromatic hydrocarbons (PAHs) are the most widely studied and discussed. In addition to their potential toxicity, both groups contain carcinogenic species. Heavy metals, as well as PAHs, are capable of bioaccumulation, depending on the element or compound’s characteristics and the vegetable species. Some leafy vegetables can accumulate these toxic materials in significant quantities. As dietary uptake is considered the major exposure route of both heavy metals and PAHs, the consumption of impacted vegetables might even pose human health risks. This recent review summarises available data reported on heavy metal and PAH accumulation in urban environments, specified by vegetable species. Also, the assessment of possible human impact is given.