Health benefits of 'grow your own' food in urban areas: implications for contaminated land risk assessment and risk management?

Abstract

Compelling evidence of major health benefits of fruit and vegetable consumption, physical activity, and outdoor interaction with 'greenspace' have emerged in the past decade - all of which combine to give major potential health benefits from 'grow-your-own' (GYO) in urban areas. However, neither current risk assessment models nor risk management strategies for GYO in allotments and gardens give any consideration to these health benefits, despite their potential often to more than fully compensate the risks. Although urban environments are more contaminated by heavy metals, arsenic, polyaromatic hydrocarbons and dioxins than most rural agricultural areas, evidence is lacking for adverse health outcomes of GYO in UK urban areas. Rarely do pollutants in GYO food exceed statutory limits set for commercial food, and few people obtain the majority of their food from GYO. In the UK, soil contamination thresholds triggering closure or remediation of allotment and garden sites are based on precautionary principles, generating 'scares' that may negatively impact public health disproportionately to the actual health risks of exposure to toxins through own-grown food. By contrast, the health benefits of GYO are a direct counterpoint to the escalating public health crisis of 'obesity and sloth' caused by eating an excess of saturated fats, inadequate consumption of fresh fruit and vegetables combined with a lack of exercise. These are now amongst the most important preventable causes of illness and death. The health and wider societal benefits of 'grow-your-own' thus reveal a major limitation in current risk assessment methodologies which, in only considering risks, are unable to predict whether GYO on particular sites will, overall, have positive, negative, or no net effects on human health. This highlights a more general need for a new generation of risk assessment tools that also predict overall consequences for health to more effectively guide risk management in our increasingly risk-averse culture.

Heavy metal accumulation in vegetables grown in urban gardens

“…It is recognized that the risk of contaminants accumulating in air, soil, and water can influence the product quality and healthiness (Al Jassir et al 2005;Leake et al 2009). Given the health risk associated with their consumption, the European Union has defined maximum levels of lead and cadmium to be found in vegetables.…”

Building capacity through urban agriculture: report on the askîy project

“…19 Natural assets in urban agriculture are those that increase exposure to outdoor physical activity (such as green space), providing major health benefits. 20 Improving natural assets in the urban environment is essential for a healthy population now and in the future.…”

Community based bioremediation: grassroots responses to urban soil contamination

“…There are currently an estimated 18,000 community gardens in the US and Canada alone (ACGA, n.d.). Such efforts may have the potential to provide city residents with a significant amount of their nutritional needs, and improve the overall quality of urban life for many (Leake et al, 2009). …”