Turning "environmental regulation" into a unified bloc that must be either supported or opposed in totality is a manipulative political maneuver and it should be forcefully rejected.
Regulations are not people, and they don't have rights. It is fair and reasonable to demand that environmental regulation justify its existence with hard, scientifically verifiable data or else get chopped. Clearly, banning leaded gasoline has that kind of justification, and therefore I'm strongly in favor of maintaining that ban and extending it wherever it isn't in place yet. The same reasonable standard should be applied to other regulations across the board.
In 1981 Reagan made cost benefit analysis a requirement for EPA.
For example in 1984: the EPA " estimates that the benefits of reducing lead in gasoline would exceed the costs by more than 300 percent.... These benefits include improved health of children and others"
Trump has just scrapped the requirement to cost in human health.
I wonder if removing lead would meet the new standard.