Trace Metal Contaminations in Bangladeshi Rice: Their Concentration and Risk Assessment.

Bangladesh has one of the highest per capita rice consumption worldwide. However, heavy metals from the soil and contaminated irrigated water are translocated into rice grains and pose a health hazard to humans in Bangladesh. We investigated trace metal contamination in rice cultivated in three sites in Bangladesh, to screen heavily contaminated trace metals and to assess the health risk via rice consumption. Rice was cultivated using groundwater in rural areas of Bangladesh and contaminated river water near Dhaka City on 30 rice cultivars. The metals contained in rice grains were measured using inductively coupled plasma atomic emission spectroscopy (ICP-AES) to investigate their contamination levels. Hazard quotient values were calculated based on the measured concentrations to assess human health risks associated with rice consumption. We showed that rice grown with groundwater and contaminated river water irrigation in Bangladesh was contaminated with different trace metals, particularly, Pb and As. The mean and maximum hazard quotient values of Pb and As were 1.4 and 3.2, and 0.42 and 1.2, respectively, implying that these rice consumption may adversely affect the health of the people living in the contaminated areas. Moreover, Cd, Mn, Ni, and Zn were detected at relatively high concentrations in rice grains irrigated with river water contaminated with industrial wastewater around Dhaka City. No dependence on water sources, such as groundwater and river water, was found for As and Pb concentrations in rice. In addition to the previously investigated As pollution, this study demonstrated that Pb contamination of Bangladeshi rice was a serious problem for the health of Bangladeshis. [ABSTRACT FROM AUTHOR]