Heavy metal(loid)s and health risk assessment of Dambulla vegetable market in Sri Lanka.

Abstract

Vegetables are essential for a healthy diet in humans. However, vegetables can carry harmful metal(loid) contaminants such as As, Cd and Pb which are deleterious to health in the long term. It has been postulated that long-term heavy metal(loid) exposure by vegetable consumption is associated with chronic kidney disease of unknown aetiology (CKDu) that prevails in North Central Province of Sri Lanka. We performed a human health risk assessment to identify if there is any link between heavy metal(loid) exposure from vegetable consumption and the prevalence of CKDu. The study includes a survey of food consumption in CKDu-impacted areas and determination of the heavy metal(loid) contents of market vegetables. We found that Solanum tuberosum (potato) and Momordica charantia (bitter gourd) accumulated Pb to a greater extent than other vegetables and exceeded the permissible concentration for foodstuffs. The Cd content of Solanum melongena (Brinjal) also exceeded permissible levels. However, the As content was below permissible levels for all the vegetables tested. The weekly total heavy metal(loid) intake of Cd, As and Pb in vegetables in CKDu-impacted areas was lower than permissible limits. The consumption of an average amount of vegetables does not pose a chronic health risk to the consumers. There was no evidence of a link between the consumption of heavy metal(loid)s in vegetables and CKDu. Since, few vegetables showed marked heavy metal(loid) accumulation, periodical monitoring of heavy metal(loid) concentrations in vegetables will be beneficial for avoidance of future possible health risks.