When it comes to climate change, we often think of the cars we drive and the energy we use in our homes and offices. They are, after all, some of the biggest contributors to greenhouse gas emissions. But what about the toast you ate for breakfast this morning?
A new study published Monday in Nature Plants breaks down the environmental cost of producing a loaf of bread, from wheat field to bakery. It finds that the bulk of the associated greenhouse gas emissions come from just one of the many steps that go into making that loaf: farming.
They collected and analyzed data for emissions involved at every step of the process, including growing the wheat, fertilizing it, harvesting the crop, transporting the grains to the mill, grinding the grains into flour, transporting the flour to a bakery and then baking and packaging a loaf of bread. Scientists call this a life cycle analysis.
“We found that over half of the environmental impacts of producing a loaf of bread come from wheat cultivation,” says Goucher. “The interesting thing is that 40 percent is attributable just to the use of ammonium nitrate fertilizers alone, which is a huge amount, when you consider it.” The fertilizers also cause a lot of water pollution when they run off into streams and rivers.
Leave a Reply