Trace elements in two staple cereals (rice and wheat) and associated health risk implications in Bangladesh

Concentrations of fourteen trace elements (Cd, As, Pb, Cr, Ni, Zn, Se, Cu, Mo, Mn, Sb, Ba, V and Ag) in the composite samples of most frequently consumed two staple foods, i.e. rice and wheat (collected from 30 different agroecological zones for the first time in Bangladesh) were measured by ICP-MS. The mean concentrations (mg/kg fresh weight) of Cd, As, Pb, Cr, Ni, Zn, Se, Cu, Mo, Mn, Sb, Ba, V and Ag were found as 0.088, 0.321, 0.713, 0.183, 0.213, 13.178, 0.0256, 1.985, 0.102, 4.654, 0.0033, 0.144, 0.081 and 0.007 and 0.011, 0.281, 0.221, 0.352, 0.145, 15.472, 0.245, 1.894, 0.209, 22.077, 0.0012, 3.712, 0.023 and 0.0013 in rice and wheat samples, respectively. Dietary risk of human health (non-carcinogenic and carcinogenic risks) was assessed by USEPA deterministic approaches. Total target hazard quotient (THQ) values for As and Pb were higher than 1, suggesting that people would experience significant health risks from consuming rice and wheat. However, the THQ of other metals were all less than 1. Also, the estimation showed that the target carcinogenic risk (TR) of As and Pb exceeded the accepted risk level of 1 × 10(-6). Moreover, concerning the nutritional requirements of essential elements for a sound health, the recommended doses for the daily intake of Mn was conveniently supplied by the studied cereals; however, Cr, Zn, Se, Cu and Mo were below the recommend daily allowances (RDAs). Thus, the carcinogenic and non-carcinogenic risk of As and Pb with lower supplementation of essential elements via staple foods for Bangladeshi people is a matter of concern.