Business groups reacted with alarm and environmentalists with applause to the U.S. Environmental Protection Agency's formal declaration Monday that greenhouse gas emissions endanger human health, clearing the way for federal regulation.

KEITH MCCOY, VICE PRESIDENT OF ENERGY AND RESOURCES POLICY,

NATIONAL ASSOCIATION OF MANUFACTURERS

The NAM supports cost-effective efforts to address climate change but believes the appropriate authority to address this is through Congress. EPA is moving forward with an agenda that will put additional burdens on manufacturers, cost jobs and drive up the price of energy.

JACK GERARD, PRESIDENT, AMERICAN PETROLEUM INSTITUTE

This action poses a threat to every American family and business if it leads to regulation of greenhouse gases under the Clean Air Act. Such regulation would be intrusive, inefficient, and excessively costly. It could chill job growth and delay business expansion. The Clean Air Act was meant to control traditional air pollution, not greenhouse gases that come from every vehicle, home, factory and farm in America. A fit-for-purpose climate law is a much preferred solution.

CHARLES DREVNA, PRESIDENT, NATIONAL PETROCHEMICAL &

REFINERS ASSOCIATION

Individual American consumers and businesses alike will be dramatically affected by this decision that, frankly, is based on selective science, a weak legal and policy foundation, and a failure to account for numerous uncertainties and assumptions in the models it relies on. This is yet another example of federal policymakers failing to consider the long-term consequences of a regulatory action for consumers and the economy as a whole.

DAVE MCCURDY, CHIEF EXECUTIVE, ALLIANCE OF AUTOMOBILE
All industries will be called upon to reduce carbon emissions. Automakers play an important role. More technology is on its way to market. We will need to use every engineer we have and every investment dollar available to make our vision of sustainable mobility a reality.

MANUFACTURERS

ENVIRONMENT:

CARL POPE, EXECUTIVE DIRECTOR, SIERRA CLUB

As the major global warming summit begins this week in Copenhagen, this announcement couldn't come at a more important time. The Obama administration has followed through on its pledge to act and is demonstrating that the U.S. has turned away from eight years of inaction under the Bush administration.

EMILY FIGDOR, FEDERAL GLOBAL WARMING PROGRAM DIRECTOR,
This is the most significant step the federal government has taken on global warming. The stage is now set for EPA to hold the biggest global warming polluters accountable. The Senate also must act to set overall pollution-reduction goals and to accelerate the move to clean energy, but it's up to EPA to crack down on pollution from cars and mega industrial polluters, like coal-fired power plants.

ENVIRONMENT AMERICA

CONGRESS:

REPRESENTATIVE EDWARD MARKEY, MASSACHUSETTS DEMOCRAT AND

CO-AUTHOR OF CARBON-CAPPING LEGISLATION:

Now that the U.S. government has officially ended its era of climate denial, the real endangerment to our planet comes from those who continue to deny the science and delay taking any action. The finding that global warming pollution poses a threat to human health and our environment is based on mountains of data accumulated from thousands of scientists over the course of decades. The molehill recently manufactured by a few climate deniers does not change that. President Obama and the United States Congress can now travel to Copenhagen armed with regulatory credibility and emission reduction targets from the Waxman-Markey legislation. The world is watching, and the United States is acting.

(Reporting by Deborah Zabarenko; Editing by Eric Beech)