But perhaps surprisingly, the story hasn't killed the trend, nor has it had much of a negative effect on the three salons highlighted in the story.

"It gave us a huge plug," said Harley DiNardo, owner of Shampoo Avenue B in New York, who said he has hired two extra staffers to help out at the salon to meet sudden demand for the treatment. Many of his new customers have reported finding the salon in Allure, he said. "We didn't know if the article was going to help us or hurt us," he said. "I felt like [writer Mary A. Fischer] was going to do a positive thing but she basically tried to scare everyone. There are way worse smells and chemicals that you can put in your hair. It doesn't damage your hair. There shouldn't be any concern if the stylist knows what they're doing. We're very, very busy. The phone still rings off the hook."

Business is so good, DiNardo said, that he and an employee are becoming the U.S. distributors of the solution, for which DiNardo traveled to Brazil. He plans to train other salons in its use.

The owner of the Argyle Salon & Spa in Los Angeles also said there had been a noticeable uptick in demand for the procedure, citing three walk-ins on Saturday alone, each mentioning the Allure story. (Mauricio Ribeiro, the Brazilian stylist at Argyle who pioneered the use of the solution, did not return calls.) The third salon mentioned in the magazine, Spalano Salon & Spa in Boca Raton, Fla., has stopped using the solution because of health concerns. "When we learned what it is, we stopped immediately," said co-owner Emma Bezdek.

Allure editor in chief Linda Wells was flummoxed. "It's so illogical that people would willfully pursue something that they know is dangerous," she said. "But I do think that this is a part of the phenomenon of the power of vanity, and some women will just ignore the consequences." She compared it to women afraid to quit smoking lest they gain weight. As to whether a jaded public had become skeptical of health risks reported in the media, she said, "We're not talking about whether red wine raises or lowers cholesterol. We're talking about formaldehyde, which is a known carcinogen." — I.C.