By RUTH LA FERLA

The reaction to a fragrance can be visceral, and personal. That is not news to Luca Turin, a scientist and fragrance expert .
He describes Attrape-Coeurs, an amber violet perfume from Guerlain, as “an intense radiant Wurlitzer organ blast of rose violet and iris notes,” but says of Creed’s Love in White: “If this were a shampoo offered with your first shower after sleeping rough for two months in Nouakchott, you’d opt to keep the lice.”
Mr. Turin, author of “Perfumes: The Guide,” written with his wife, Tania Sanchez, is a dominant voice in a chorus of critics airing their views in books and magazines and, increasingly, on the Web.
That chatter, however, is the bane of the fragrance industry .
Today reviewers on Web sites and blogs like aromascope.com, scentzilla. com, boisdejasmin.com and perfumeposse. com are fierce, responding to certain fragrances with rapture or, as often, with venomous contempt.
An enthusiast on nowsmellthis. blogharbor.com described Poison, from Dior, as “a warm, luxurious velvet blanket draped across a satin settee. On the same site, the perfume was assailed as “a railroad spike through the brain.”
When they wish to be especially critical, bloggers designate a scent as a “scrubber,” the kind of smell you can’t wash off fast enough. Not surprisingly, these critics’ uncensored comments have been anathema to the Estee Lauders and Cotys of the world .
“No question, the industry people are unnerved,” said Rochelle R.
Bloom, the president of the Fragrance Foundation, a trade group. “I often get calls from executives pleading, ‘Can’t you do something about all this chatter?’ ”
Commentators on coty.com prompted Coty, which makes fragrances by David Beckham and Jennifer Lopez, among others, to think of reissuing its greatest hits, scents like Emeraude and L’Origan, said Stephen C. Mormoris, a senior vice president of global marketing.
Such developments cannot come soon enough for Ms. Sanchez. In “Perfumes: The Guide,” she chided that the perfume industry hasn’t yet figured out the benefits of relaxing control.” She told of a prominent blogger threatened with a lawsuit by a perfume company because she had deemed its product only “O.K.,” and “a little disappointing.”
“When a sleek luxury goods company unleashes its lawyers on a suburban mom for not liking their new fragrance,” Ms. Sanchez wrote, “we know the world is changing.”