Probably because you don't find a list from the EPA.
The two categories are very similar, they are sort of aimed at the same result but have slightly different criteria. e.g. the EPA considers exposure levels, IARC requires at least some human evidence. So you wouldn't say one is stricter than the other, just different ways of skinning a cat.
The two categories are very similar, they are sort of aimed at the same result but have slightly different criteria. e.g. the EPA considers exposure levels, IARC requires at least some human evidence. So you wouldn't say one is stricter than the other, just different ways of skinning a cat.