"We have no interest in regulating dirt," Johnson said during a meeting with
The EPA's recent rewriting of dust emissions rules did not exempt farms after scientific studies failed to determine whether or not field dust, commonly kicked up during harvest and other farm work, poses a threat to human health.
Johnson says he doesn't think that dust emissions from fields would be dangerous to humans, easing farmers' fears that the EPA would interfere with farming practices. Grassley has been a vocal opponent of the EPA's failure to exempt farms from the rules, and he told farmers to pass Johnson's comments on to their state officials.
The EPA will focus on dust from industrial and city sources, Johnson says. Studies have shown that dust from those sources create much stronger health risks, including links to asthma and other lung problems.