The Grapevine

Climate Change Effects May Soon Expose Billions Of People To Toxic Rice

Many parts of the world have been experiencing the growing impact of climate change. The rising temperatures are expected to affect the sea levels and global food supply in the future. 

A new study, published in the journal Nature Communications, found that the world may soon see a dramatic drop in rice production. Climate change has been causing changes to soil processes, which increase levels of toxic arsenic in rice. 

“I just didn’t expect the magnitude of impact on rice yield we observed,” Scott Fendorf, study co-author and a professor of earth system science at Stanford University, said. “What I missed was how much the soil biogeochemistry would respond to increased temperature, how that would amplify plant-available arsenic, and then—coupled with the temperature stress—how that would really impact the plant.”

Researchers said the increasing temperatures combined with flooding could significantly increase arsenic from the soil and being absorbed by rice plants. Arsenic is a naturally occurring, semi-metallic chemical linked to cancer, lung disease, skin lesions and even death, Futurity reported.

“By the time we get to 2100, we’re estimated to have approximately 10 billion people, so that would mean we have 5 billion people dependent on rice, and 2 billion who would not have access to the calories they would normally need,” Fendorf said. “We have to be aware of these challenges that are coming so we can be ready to adapt.”

The findings come from the analysis of simulated climate conditions when the global temperature increases by 5 degrees Celsius. Researchers said the study is the first to look into impact of shifts in climate on soil conditions. 

They examined the effects of climate change with a medium-grain rice variety in soil from the rice-growing region of California. The team exposed the rice to controlled temperature, carbon dioxide concentrations and soil arsenic levels.

Results showed that with increased temperatures, microorganisms disrupted the arsenic in the soil, which led to higher toxin in the soil water surrounding rice plants. The increased levels of arsenic also blocked nutrients and reduced plant growth and development.

The researchers said with the current climate conditions, many regions may soon see the same changes in soil. The study predicts that by 2100 the rice production could drop by 40 percent.

However, researchers noted there are ways to prevent such decrease and continue a stable production of rice. Fendorf said revisions to soil management and farmers’ ability to breed varieties of rice that can adapt to new conditions would help address the potential issue. 

Rice A farmer spraying herbicide to rice plants before harvest season. Pixabay