Levels of Cr, Cu and Zn in Food Stuffs from a Wastewater Treatment Wetland, Phnom Penh: A Preliminary Assessment of Health Risks
The naturally occurring wastewater treatment wetlands of Phnom Penh, Cambodia, also are home to a peri-urban community that actively harvests various food stuffs (vegetables, snails, fish) from the wetlands. Concern has been expressed about the potential health implications of eating food stuffs taken from the wetlands. Therefore, the objectives of this study were to identify the uses (e.g. fishing, shellfish cultivation, and aquatic plant harvesting) of wetlands through direct survey of users; analyze food stuffs to assess metals (Zn, Cu and Cr) levels; and develop simple contaminant exposure estimates for the survey participants. Sample collection and social surveys were conducted to fulfill the objectives of this research. It was found that the metals concentrations in vegatables were low compared to fishes and snails. The contaminant exposure estimates (risk assessment) of Morning glory (Ipomoea aquatica), the predominant vegetable in the study area, and fish, showed that Zn, Cu and Cr originating from consumption of these food stuffs still do not pose any serious health risk to the community (with the exception of Cr for children eating fish at one sample site). A higher risk was identified for children consuming snails, specifically with respect to Cr.
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