Determination of Selected Metals and Metalloids in Different Types of Rice by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES)

Pantanal is a unique biome located in Brazil, with diverse fauna and flora, being home to native species such as the rice types Oryza latifolia and Oryza rufipogon. Rice is a staple food for two-thirds of the population, with increasing consumption, especially in Asia, regions of Sub-Saharan Africa, countries in the Caribbean, and Latin America. The per capita rice consumption had an average consumption of 160 g/day. However, rice consumption may lead to the intake of other harmful substances to health, such as toxic metals/metalloids. The determination of potential hazards in native species is crucial in maintaining the local population in good health. In this study, we determined the concentration of essential elements and potentially toxic elements in seven different types of Brazilian rice grains, including the two Pantanal native species O. latifolia and O. rufipogon, using ICP-OES to identify their nutritional richness or potential toxicity. The contaminant with the highest HQ levels was chromium, with an HQ above one only in the native species. All species (commercial and native) showed carcinogenic risk considering inorganic arsenic. Rice exhibits duality in its classification, providing nutritional content and leading people to potential risks of overexposure to toxic elements. While rice can be part of a healthy and nutritious diet, more studies should be conducted on avoiding or remedying contamination with toxic elements.