Summary: After water, concrete is the most consumed substance on the planet and its production is expected to grow from 4.4 billion tons to 5.5 billion tons by 2050. But its production, which involves cement, comes at a huge environmental cost -- accounting for almost eight percent of carbon emissions globally. Mori Rothman reports on the industry's attempt to reduce concrete's carbon footprint with cleaner cement. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders
