Lumber Liquidators' flooring products pose more of a cancer risk than originally announced, the Centers for Disease Control and Prevention has announced.
"Health risks of people who have the laminate flooring are being revised to reflect greater exposure to formaldehyde, which could cause eye, nose, and throat irritation for anyone,"
the CDC wrote in a Monday statement.
"The estimated risk of cancer associated with exposure to the flooring increased," it added.
Formaldehyde is a known carcinogen that causes myeloid leukemia and other cancers at high levels.
According to MarketWatch.com, the new revelation sent shares of Lumber Liquidators Holdings Inc. tumbling Monday morning.
Lumber Liquidators was the subject of a negative report last year by "60 Minutes," in which it was alleged that the company's laminates sourced from China contained the dangerous chemical in amounts that exceeded California emissions standards.
The CDC said that initial tests of the risk were flawed.
"The health risks were calculated using airborne concentration estimates about three times lower than they should have been," the agency said.
"The estimated risk of cancer is 6-30 cases per 100,000 people," it concluded.
Previously, the CDC had incorrectly estimated that the cancer risk was 2-9 cases per 100,000 people.
In response to the controversy, Lumber Liquidators hired former FBI head Louis Freeh to investigated its supply chain, and cut its ties with Chinese suppliers in May 2015.