Genetically Engineered Rice Could Help Reduce Greenhouse Gas Emissions
Come 2050, there are going to be a lot more people in the world. Population projections estimate that Earth will house 9.6 billion residents by then. And the question of what they’ll all eat—and at what cost—looms.
With much of that population growth set to come in the 49 least developed countries—which the United Nations estimates will double in size from approximately 900 million in 2013 to 1.8 billion in 2050—and more than half of the world’s current population depending on rice as a staple, there’s no guessing at what most will be eating.
But with climate change threatening staple crop production in myriad ways, and staple crop production contributing to the overall increase in global emissions—food accounts for 15 to 50 percent of global emissions—answering that question is difficult without it sounding like speculative disaster fiction. Even at the current scale, rice paddies are responsible for between 7 and 17 percent of methane emissions—which are largely caused by the natural decaying processes that occur when rice fields are flooded—and with demand for rice set to increase, that amount is likely to grow. If the vital food crop presents a macro risk to the communities that depend on it, the high levels of arsenic it can contribute to in those who eat a lot of it present a micro one too, with the risk of poisoning.
When it comes to methane, there have been numerous efforts to reduce emissions, ranging from developing a cap-and-trade program for rice farmers in California to changing irrigation practices in India. Researchers from China, Sweden, and the United States, however, have taken a different, more controversial approach: a genetic “tweak,” as Scientific American puts it, affecting the way rice plants store energy, which would reduce their greenhouse gas emissions.
“This type of rice may be particularly useful in a predicted climate with higher temperatures, which will accelerate methane emissions from paddies, as methane emissions are temperature dependent,” Chuanxin Sun, a plant biologist at the Swedish University of Agricultural Sciences and the lead author of a study reporting the findings published in Nature last week, told Scientific American. “The [GMO] rice may counteract the acceleration.”
But if the years-long drama surrounding Golden Rice is anything to judge by, getting the reduced-methane strain into production won’t be easy. Despite the G.E. variety’s potential to reduce a host of illnesses associated with low beta-carotene intake (which leads to vitamin A deficiencies) in developing nations and being recognized as safe to human health and the environment, the project has been stalled owing to opposition to G.E. foods.
While a nearly endless series of trials and debates over the new genetically engineered strain, which relies on a single barley gene to achieve its lower methane emissions, will unfold before it can be grown at scale, another study, published in PLOS One, shows an immediate way to make rice safer for the people who rely on it.
Researchers at Queen's University Belfast found that cooking the grain in multiple changes of water, rinsing between changes, rather than in a single volume that the rice absorbs, resulted in a significant drop in arsenic levels—as much as 57 percent. Low levels of arsenic are common, and safe, in rice, but there are parts of the world that have higher levels in both soil and water that can cause health issues for populations that rely heavily on rice.
Andrew Meharg, the lead researcher, suggested that rice cookers could be developed to prepare the rice in such a manner. But in the meantime, it could be cooked using one of the methods in the study: by percolating the grains in a coffeemaker.