By now, we’re well aware of the purported health and environmental benefits of buying organic products, whether or not we ultimately opt for that slightly pricier stalk of Brussels sprouts. Buying local and from farmers’ markets is also important in not only supporting small businesses but also in supporting better growing practices.

A team of researchers from the University of Minnesota, Yale University and the U.S. Department of Agriculture found that levels of nitrous oxide emissions have risen in the corn farms of the Midwest, also known as the Corn Belt, according to Mother Jones. Nitrous oxide, a greenhouse gas with “nearly 300 times the heat-trapping power of carbon dioxide,” is emitted from fertilizer that is used in this area.

Mother Jones reports that “scientists had been undercounting nitrous oxide emission in the Corn Belt by about 25 gigagrams annually — the equivalent of about 1.6 million cars on the road.” Those are some pretty startling figures. The research team measured the nitrous oxide emissions of 19 streams over two years in southeastern Minnesota to come to this conclusion.

If you’re not already buying your corn organic or from farmers’ markets, perhaps now is the time to start.