In December 2009, EPA ruled that climate change caused byemissions of greenhouse gases threatens the public's health and theenvironment. Since that time, EPA has received ten petitions challenging theirdetermination. On July 29, 2010, EPA announced that it has denied these petitions.

Thepetitions to reconsider EPA's "Endangerment Finding" claimed thatclimate science can't be trusted, and asserted a conspiracy that callsinto question the findings of the Intergovernment Panel on Climate Change, the U.S. National Academy of Sciences, and the U.S. Global Change Research Program. The EPA seriously considered these petitions, however, found no evidence to support the claims, and has denied them.  For further information, see:http://www.epa.gov/climatechange/endangerment/petitions.html.