Colorado State University researchers have outlined new soil management strategies designed to reduce the uptake of arsenic, cadmium and mercury into rice grains, potentially helping protect food security and human health.
In a perspective published in Nature Reviews Earth & Environment, the researchers propose methods to alter soil chemistry so toxic metals become immobilized and less available for uptake by rice plants.
Rice is a staple food for more than half of the world's population and plays a critical role in food security, particularly in low-income, food-deficit countries. However, toxic metal contamination in rice paddies poses risks to both food security and public health.
The proposed strategies are intended for rice paddies with low to moderate contamination, where intensive remediation methods such as physically replacing soil are generally impractical because of their cost and scale.
The researchers' approach would target toxic metals at several stages of rice production. Soil management during tillage could help stall toxins before they move through the soil. Chemical reactions involving nutrient inputs could further immobilize toxic metals, while nanomaterials could reinforce barriers against metal uptake during the flowering stage.
The goal is to prevent arsenic, cadmium and mercury from reaching rice grains, the portion of the plant consumed by people.
Thomas Borch, a CSU professor of soil and crop sciences, co-authored the perspective with University Distinguished Professor Jan Leach and Sean Fettrow, a postdoctoral researcher in the Borch lab. Liping Fang of the Guangdong Academy of Sciences in China is the paper's first author.
The researchers said their proposed soil management strategies could provide alternatives to expensive remediation methods for addressing toxic metal contamination in rice production.
Source: Colorado State University, "Researchers outline strategy to prevent toxic metals from tainting rice"