Exposure to Inorganic Arsenic in Rice in Brazil: A Human Health Risk Assessment

Abstract

In certain populations, rice is the main source of exposure to inorganic arsenic (iAs), which is associated with cancer and non-cancer effects. Although rice is a staple food in Brazil, there have been few studies about the health risks for the Brazilian population. The objective of this study was to assess the risks of exposure to iAs from white rice and brown rice in Brazil, in terms of the carcinogenic and non-carcinogenic effects, and to propose measures to mitigate those risks. The incremental lifetime cancer risk (ILCR) and hazard quotient (HQ) were calculated in a probabilistic framework. The mean ILCR was 1.5 × 10−4 for white rice and 6.0 × 10−6 for brown rice. The HQ for white and brown rice was under 1. The ILCR for white and brown rice was high, even though the iAs concentration in rice is below the maximum contaminant level. The risk for brown rice consumption was lower, which was not expected. Various mitigation measures discussed in this report are estimated to reduce the risk from rice consumption by 5–67%. With the support of public policies, measures to reduce these risks for the Brazilian population would have a positive impact on public health.

Essential and Toxic Elements in Infant Cereal in Brazil: Exposure Risk Assessment

“…Rice is known to store higher levels of As than do other crops [59]. Toledo et al [60] found a high cancer risk There are no guidelines for the acceptable risk related to carcinogenic contaminants in food. However, if we considered the acceptable risk level suggested by the WHO [58] for carcinogenic compounds in drinking water (10 −5 ), as did authors such as Shibata et al [4], the mean ILCR for rice cereal in our study would be 2.6 times higher than that level, and multi-grain cereal containing rice would be 1.3 times higher.…”

“…Rice is known to store higher levels of As than do other crops [59]. Toledo et al [60] found a high cancer risk associated with rice consumption in Brazil due to iAs exposure. In the present study, the mean ILCR for rice cereal was two times higher than that for multi-grain cereal, and approximately 12 times higher than that for non-rice-based cereal.…”