In a decision that could have repercussions for many environmental regulations, the Environmental Protection Agency has revised its cost-benefit analysis to eliminate consideration of the dollar value of health benefits from its regulations on fine particles and ozone because there is too much uncertainty in estimates of those economic impacts.

The decision is part of a final rule on pollution requirements on new power plant turbines that burn fossil fuels. Although the rule does not apply to mobile sources of emissions, such as commercial trucks, the change in policy analysis will likely be implemented in the future for mobile sources as well.

The agency has clarified that it is still considering health benefits in rulemakings. But it will not assign a dollar amount to those benefits until further notice, as it reconsiders the way it assesses those numbers.

In its regulatory analysis supporting the final rule, the agency said: “The EPA is obligated to present the Agency’s best scientific understanding when developing policies and regulations and to ensure the public is not misled regarding the level of scientific understanding. Historically, however, the EPA’s analytical practices often provided the public with a false sense of precision and more confidence regarding the monetized impacts of fine particulate matter (PM2.5) and ozone than the underlying science could fully support, especially as overall emissions have significantly decreased, and impacts have become more uncertain.”

In addition, the rulemaking stated, “the EPA historically provided point estimates instead of just ranges or only quantifying emissions, which leads the public to believe the Agency has a better understanding of the monetized impacts of exposure to PM2.5 and ozone than in reality. Therefore, to rectify this error, the EPA is no longer monetizing benefits from PM2.5 and ozone but will continue to quantify the emissions until the Agency is confident enough in the modeling to properly monetize those impacts.”