Contamination of vegetables with toxic metals is one of the most important contributing factors to ill health
throughout the world, more so because vegetables are considered essential for human health and their
consumption is highly recommended by health authorities. The aim of this study was to determine the
concentrations of selected essential elements (Fe, Cu, Mn, Mo, Zn) and toxic elements (As, Cd, Cr, Pb) in
common vegetables sold for human consumption in supermarkets and open market of Maun village, Botswana.
Five vegetables (cabbage, rape, tomatoes, onions and potatoes) were purchased from different selling points,
washed with de-ionised water, cut into small pieces and digested with aqua regia on a block digester, following
the US. EPA method 200 - 7 and analysed for metal content using Inductively Coupled Plasma - Atomic
Emission Spectroscopy (ICP-AES). The results showed that concentrations of essential and toxic metals varied
with the type of vegetable and also with the market category (supermarket or street vendor). The highest
concentration of essential elements was obtained from cabbage with a Zn concentration of 135.4mg/Kg and the
lowest was from onion with a Mo concentration of 1.35mg/Kg. For toxic elements the highest concentration was
obtained from rape vegetable with a Pb concentration of 4.73mg/Kg and the lowest from the same vegetable
with Cr concentration below the detection limit. Also observed was that leafy vegetables, especially cabbage,
had the highest concentrations of most trace metals. It was concluded that vegetables sold in Maun had sufficient
levels of essential elements but also some had high concentrations of toxic metals. We thus recommend
consumption of vegetables from the studied markets with reduced frequency to avoid metal poisoning.