Californians are required to disclose the radon level in their home, if known, before transferring it to a new owner.

Nevadans are not.

In both states, renters are particularly vulnerable.

“There are no regulations to protect renters from radon in Nevada,” said Susan Howe, radon education program director for the University of Nevada Cooperative Extension. “There are no regulations dealing with radon in Nevada, period. There are no laws to protect people when they buy or build homes.”

More people die each year from radon exposure than from drunk driving accidents, falls in the home, drownings and home fires, according to the Environmental Protection Agency.

The known carcinogen — undetectable by sight, smell or taste — is the leading cause of lung cancer among nonsmokers and the second-leading cause of lung cancer for smokers. Radon exposure causes an estimated 21,000 deaths per year in the United States.

SOUTH LAKE TAHOE, Calif.—Elevated levels of radon pose a significant health risk to California residents around Lake Tahoe, according to a report released by the California Geological Survey.
An estimated 23,400 people live in homes were radon is likely to equal or exceed the U.S. Environmental Protection Agency's recommended action level of 4 picocuries per liter, the agency reported.

The survey found about 40 percent of California homes around Tahoe are at or above that level, and that the basement measurement from one house was more than 20 times that level.

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