The Environmental Protection Agency (EPA) is now only counting costs to businesses when considering regulation on key pollutants, internal documents show, rather than considering human lives saved by such caps.

For the first time in decades of the practice, The New York Times reports, the EPA will effectively set the cost of a human life at $0 when doing cost-benefit analysis for fine particulate matter (PM2.5) or ozone pollution — two air pollutants that can cause lifelong respiratory issues and are estimated to cause tens of thousands of premature deaths every year in the U.S.

An email by a supervisor reported by the Times, as well as a rule posted online Monday by the agency, says that there are “uncertainties” associated with monetized impacts of the two pollutants — seemingly using the concept of uncertainty in scientific analysis in order to discard public health regulations estimated to have saved hundreds of thousands, if not millions, of lives.