Appraisal of heavy metal(loid)s contamination in rice grain and associated health risks

Abstract

The development of the economy and society makes heavy metal(loid)s pollution more serious, and contamination of rice grains by heavy metal(loid)s is a worldwide problem. In order to appraise the health risks associated with heavy metal(loid)s in rice grains, we performed a metaanalysis based on the datasets collected from the literature (n= 248) between 2010 to 2023.The global mean values obtained for heavy metal(loid)s were in the following order: Fe (214.1µg g-1 ) > Zn (38µg g-1 ) > Mn (29.3µg g-1 ) > As (1.9µg g-1 ) > Cu (6.8 µg g-1 ) > Cr (3.7µg g-1 ) > Pb (6.6µg g-1 ) > Ni (7.6µg g-1 ) > Co (1.0µg g-1 ) > Cd (0.20µg g-1 ) and Hg (0.01µg g-1 ). The relatively higher contents of Pb, As, Cu, Hg and Zn were reported in China; Cr, Fe, Mn, Zn and Cu in Bangladesh; and Fe, Zn and Mn in Nigeria and India.The hazard quotient values of As were found greater than one for all the studied countries in both adults and children. These results suggest that contamination of rice grains with heavy metal(loid)s might lead different countries to establish strict legal guidelines and policies for preventing heavy metal(loid)s contamination of crop cultivation near contaminated are