The EPA is trying to put to rest what it calls a "myth" that it is going to crack down on farm dust.

In letters to two senators last week, Administrator Lisa Jackson said that the agency won't expand its current air quality standards to include dust created by agriculture.

Republicans and some farm-state Democrats have used the issue on the campaign trail, arguing that the EPA is set to penalize farmers for everyday activities. Republican presidential candidate Herman Cain said in a recent debate that the agency is "out of control" and was preparing to regulate dust.

A statement released by the agency Monday said that "EPA hopes that this action finally puts an end to the myth that the agency is planning to expand regulations of farm dust."