Under the new rules, the EPA would allow regulators to evaluate “various threshold models across the exposure range” when people are faced with potentially harmful substances, according to the Associated Press. The proposed regulation doesn’t cite radiation specifically, but critics are concerned that it could pave the way for less stringent radiation protocols that could ultimately expose people to its harmful effects.

Harmful radiation has long been a concern of the EPA. And for decades, the government agency has instituted policies that severely limit its exposure to humans for fear of cancer risks. Industry experts, however, caution that any loosening of those restrictions could cause health problems.

For its part, the EPA cautioned against believing any rule changes would cause health problems. EPA spokesman John Konkus noted that the “regulation doesn’t talk about radiation or any particular chemicals.” Konkus added that the EPA will continue to use the “linear-no-threshold model for population-level radiation protection purposes which would not, under the proposed regulation that has not been finalized, trigger any change in that policy.”

The original press release proposing the change, however, includes a quote from a toxicologist named Edward Calabrese that said the rule could be “a major scientific step forward” in evaluating risks associated with “chemicals and radiation.”