The downside of UBI is that it costs an awful lot. According to the researchers, the companies that pollute the environment could pay for it because taxing carbon emissions alone would generate about US$2.3 trillion a year. Environmental damage and poverty both pose huge risks to society," says economist Ussif Rashid Sumaila from the University of British Columbia. "By requiring that major polluters pay to clean up their own messes, or the 'polluter pays principle', you have a creative approach to address both issues."