Heavy metals in Australian grown and imported rice and vegetables on sale in Australia: Health hazard

Abstract

Dietary exposure to heavy metals is a matter of concern for human health risk through the consumption of rice, vegetables and other major foodstuffs. In the present study, we investigated concentrations of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) in Australian grown and imported rice and vegetables on sale in Australia. The mean concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn in Australian grown rice were 7.5µgkg−1, 21µgkg−1, 144µgkg−1, 2.9mgkg−1, 24.4mgkg−1, 166µgkg−1, 375µgkg−1, and 17.1mgkg−1 dry weight (d. wt.), respectively. Except Cd, heavy metal concentrations in Australian grown rice were higher than Bangladeshi rice on sale in Australia. However, the concentrations of Cd, Cr, Cu, and Ni in Indian rice on sale in Australia were higher than Australian grown rice. The concentrations of Cu and Ni in Vietnamese rice, and that of Cd, Cr, Cu, Ni, and Pb in Thai rice on sale in Australia were also higher than Australian grown rice. Heavy metal concentrations in Pakistani rice on sale in Australia were substantially lower than that in Australian grown rice. In Australian grown rice varieties, the concentrations of heavy metals were considerably higher in brown rice varieties than white rice varieties, indicating Australian brown rice as a potential source of dietary heavy metals for Australian consumers. The mean concentrations of heavy metals in Australian grown and Bangladeshi vegetables on sale in Australia were also determined. Some of the Australian grown and Bangladeshi vegetables contained heavy metals higher than Australian standard maximum limits indicating them as potential sources of dietary heavy metals for Australian consumers. Further investigation is required to estimate health risks of heavy metals from rice and vegetables consumption for Australian consumers.