NEW YORK — Rice is under threat of becoming less nutritious due to the harmful effects of man-made CO2 gas emissions, according to a study penned by scientists from across the world.
The grain — a food staple that accounts for 25 percent of “all global calories” — has fewer vitamins in it today than ever before when it is grown in areas tainted by high levels of carbon dioxide (CO2).
CO2, the gas’ elemental symbol, is the most prevalent greenhouse gas causing climate change.
“If we do nothing,” University of Washington public health researcher Kristie Ebi told the Washington Post, “there is this potential for profound negative impacts on human health.” Ebi is one of several authors of the study, published in the journal Science Advances, which includes the contributions of scientists from China, Japan, the U.S., and Australia.
The study was conducted among 18 different varieties of rice in concentrations of CO2 spanning 568 to 590 parts per million — above the Earth’s current level of 410ppm — the highest point found in data for the last 800,000 years, a recording done earlier this month by geochemists found. The levels under the simulation were raised to reflect the planet’s upward trend of CO2 rates.
Under these conditions, folate, protein, iron and zinc amounts, as well as vitamins B1, B2, B5 and B9, all fell by as much as 30 percent.
“We know that folate deficiencies in pregnant women can result in children that have various birth anomalies,” Ebi said. “So they’re critically important, particularly for maternal and child health, but for all of us.”
Plants pull carbon from the air in order to grow, but will absorb more if there’s a high concentration of it available, the study explained. But they’re not designed to handle more CO2 than what is required for growth, meaning plants could overload their metabolisms with carbon, leaving less room for other nutrients. This, in turn, produces a less healthy food source for people.
Although this result of climate change impacts the entire world, it disproportionately harms poor and disadvantaged people the most, as rice is a nearly irreplaceable food for those of limited means.
“When you think about who consumes as a proportion of their diet the most starch,” Ebi said, “it generally is the poor, in all countries.”