Agronomic solutions to decrease arsenic concentrations in rice

Authors: LEAVITT, MARGUERITA - University Of Arkansas; Reba, Michele; SEYFFERTH, A. - University Of Delaware; RUNKLE, B.R.K. - University Of Arkansas

Submitted to: Environmental Geochemistry and Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/7/2025
Publication Date: 5/16/2025
Citation: Leavitt, M.E., Reba, M.L., Seyfferth, A., Runkle, B. 2025. Agronomic solutions to reduce arsenic in rice food products. Environmental Geochemistry and Health. 47(209). https://doi.org/10.1007/s10653-025-02508-7.
DOI: https://doi.org/10.1007/s10653-025-02508-7

Interpretive Summary: Rice plants accumulate arsenic (As) and sometimes develop grain As levels high enough to be detrimental to human health. We performed an extensive literature review of different methods for reducing the level of As in rice and we interviewed stakeholders in the rice production sector to determine current awareness of and barriers to the implementation of mitigation practices. We found that the most effective and broadly applicable practices were irrigation methods with aerobic periods such as alternate wetting and drying (AWD) and the application of silicon-rich amendments. Stakeholders indicated that the implementation of mitigation practices is most hindered by practicality and cost, and emphasized the need for cheaper and faster tests for grain As. These results are beneficial to rice producers and regulators to set achievable As limits in the food supply, particularly for rice used in the production of food products for vulnerable populations such as infants and young children.

Technical Abstract: Rice plants accumulate arsenic (As), a toxic metalloid that occurs both naturally and as a form of anthropogenic pollution in rice fields. In some instances, the rice grains develop high enough levels of As to be a risk to human health, particularly when consumed regularly or used in food products for infants and young children. The purpose of this review is to summarize evidence-based mitigation strategies for minimizing As content of rice and establish recommendations for their implementation. Mitigation strategies include irrigation management practices that introduce aerobic periods, the application of soil and foliar amendments that decrease As uptake in the plant, selecting and developing cultivars that have lower rates of As-uptake, and post-harvest processing. In addition to literature review, rice producers were interviewed to identify any barriers or knowledge gaps to the implementation of the mitigation strategies. Alternate wetting and drying irrigation showed high effectiveness in reducing As concentration in the rice grain and is also climate-smart and can be cost-neutral. Combining irrigation management with select amendments maximized the reduction of grain As concentrations. Combining treatments will allow a choice of options to accommodate different farm circumstances, though nearly all field-level treatments lack experimental evidence from trials at production-scale operations (i.e., >1 ha, with commercial management). Thus, more research is needed to confirm best management strategies at the field scale.