The Lancet: As Temperatures And CO2 Levels Rise In Tandem, Arsenic Content In World's Rice Supply Will Also Increase
Rice, the world’s most consumed grain, will become increasingly toxic as the atmosphere heats and as carbon dioxide emissions rise, potentially putting billions of people at risk of cancers and other diseases, according to new research published Wednesday in The Lancet. Eaten every day by billions of people and grown across the globe, rice is arguably the planet’s most important staple crop, with half the world’s population relying on it for the majority of its food needs, especially in developing countries. But the way rice is grown—mostly submerged in paddies—and its highly porous texture means it can absorb unusually high levels of arsenic, a potent carcinogenic toxin that is especially dangerous for babies.
Lewis Ziska, a plant physiologist and associate professor at Columbia University, has studied rice for three decades and has more recently focused his research on how climate change reduces nutrient levels across many staple crops, including rice. He teamed up with researchers from China and the U.S. to conduct a first-of-its-kind study, looking at how a range of rice species reacted to increases in temperature and carbon dioxide, both of which are projected to occur as more greenhouse gas emissions are released into the atmosphere as a result of human activities. The new study was published in The Lancet Planetary Health.
“Previous work has focused on individual responses—some on CO2 and some on temperature, but not both, and not on a wide range of rice genetics,” Ziska said. “We knew that temperature by itself could increase levels, and carbon dioxide by a little bit. But when we put both of them together, then wow, that was really something we were not expecting. You’re looking at a crop staple that’s consumed by a billion people every day, and any effect on toxicity is going to have a pretty damn large effect.”
For six years, Ziska and a large team of research colleagues in China and the U.S. grew rice in controlled fields, subjecting it to varying levels of carbon dioxide and temperature. They found that when both increased, in line with projections by climate scientists, the amount of arsenic and inorganic arsenic in rice grains also went up.
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https://insideclimatenews.org/news/16042025/half-the-worlds-people-depend-on-rice-new-research-says-climate-change-will-make-it-toxic/
https://www.science.org/doi/10.1126/sciadv.aaq1012