This is because estimates of radon risks are based on studies of cancer in humans (underground miners).

Scientists are more certain about radon risks than from most other cancer-causing substances.

The public needs to be aware of radon risks and the means to reduce and prevent these.

Working groups will collect and analyse information on radon risk, radon policies, radon mitigation and prevention as well as risk communication.

But New Jersey is spending only $1.2 million investigating the radon risk, while $1.1 billion in state and Federal money has been marked for studying and cleaning up the Superfund sites.

Federal agencies have joined together to address radon risk in the millions of homes, schools and daycare facilities that they influence.

However, we know more about radon risks than risks from most other cancer-causing substances.

This is because estimates of radon risks are based on data from human studies (underground miners).

The E.P.A. has vigorously defended its alarm call, pointing out that "radon risks are far higher than those associated with most environmental health hazards" that the agency regulates.

But several long-awaited studies designed to quantify the radon risk in homes have not found a significant cause-effect relationship at typical levels of exposure.