MATTHEW PERRONEWASHINGTON (AP) ¿ Consumers should stop using Zicam Cold Remedy nasal gel and related products because they can permanently damage the sense of smell, federal health regulators said Tuesday. The over-the-counter products contain zinc, an ingredient scientists say may damage nerves in the nose needed for smell. The other products affected by the Food and Drug Administration's announcement are adult and kid-size Zicam Cold Remedy Nasal Swabs. The FDA says about 130 consumers have reported a loss of smell after using Matrixx Initiatives' Zicam products since 1999. Shares of the Scottsdale, Ariz.-based company plunged to a 52-week low after the FDA announcement, losing more than half their value. "Loss of the sense of smell is potentially life threatening and may be permanent," said Dr. Charles Lee, of FDA's compliance division. "People without the sense of smell may not be able to detect dangerous life situations, such as gas leaks or something burning in the house." Matrixx defended the safety of its products, but said late Tuesday it will withdraw Zicam Cold Remedy Swabs and Zicam Cold Remedy Gel from the market.