False scents?

Pheromone-based fragrance manufacturers purport to have human chemistry all figured out.
Recent discoveries in the field suggest they have a lot of explaining to do.
by Michelle Chihara

A male hamster smeared with vaginal secretions from a female hamster will attract male suitors. Queen bees ensure their royal status by excreting chemicals that sterilize the other female bees around them. A female boar, after one whiff of a particular secretion from a male boar, will immediately assume the mating position.
That\'s because boars, bees, and hamsters, like other animals, respond to pheromones: chemicals that bypass conscious systems to trigger specific -- often sexual -- behaviors. Most scientists agree that humans probably also respond to pheromones. But it\'s still unclear how we receive them and what, exactly, they do to us.

What is clear is that plenty of people find the idea of pheromones enormously appealing -- enough so to fuel a small industry in pheromone-based perfumes promising to increase your sex appeal and boost your mood. For example, one called Realm, which retails for $60 a bottle, is advertised as \"the first fragrance that can make you feel . . . Self-confident. Attractive. Romantic. It works. It\'s patented.\"

Patented it is. But a recent article published by researchers in David Corey and Catherine Dulac\'s labs at Harvard University and the Howard Hughes Medical Institute at Massachusetts General Hospital shows just how far university science is from the marketing claims of perfumes such as Realm. The researchers report the discovery of a gene in rats and mice that looks as if it plays a crucial role in the detection of pheromones. Their work moves scientists closer to an understanding of how pheromones work in animals, particularly in rodents. But the article also reported another finding: that gene, which seems to be a key aspect of the rodent pheromonal system, simply does not function in humans.

This is news that Bill Horgan, CEO of the company that manufactures Realm, is trying hard to ignore. Horgan says his company, Human Pheromone Sciences (HPS), has invested between $10 million and $15 million in pheromone research since 1989, and he claims that researcher David Berliner, a primary shareholder and one of the company\'s founders, has \"identified, isolated, and synthesized\" human pheromones.

HPS did more than $10 million in sales last year; in March, the company signed two new deals, one with an international marketing firm and one with a major online retailer. Scientists outside HPS\'s own labs may not buy its claims, but that isn\'t stopping customers from buying into Realm\'s promise to \"awaken your Sixth Sense.\"

The concept of selling pheromones seems to have been around for as long as the dating expression \"the chemistry is right.\" Berliner claims to have made his initial pheromone discovery in the 1950s, and companies have been advertising pheromone-enhanced love potions in the backs of magazines for decades.

In the fragrance mainstream, there are only a couple of pheromone players. In the \'80s, Jovan (partnering with International Flavors and Fragrances, one of the perfume industry\'s biggest conglomerates) marketed a pheromone perfume called Andron, which an IFF spokeswoman says was also \"based on a lot of research.\"

Andron disappeared from the market, but Realm hit the shelves in 1994, supported by infomercials, radio ads, and a spot in Bloomingdale\'s cosmetics display. Sales took off in its first couple of years, then dipped in 1996, but now seem to be recovering. Since Realm\'s debut, magazines from Health to Newsweek have published relatively uncritical reports of its claims. Every year since Realm\'s release, a handful of newspapers and magazines -- this one included -- have run titillated columns about the exciting prospect of a \"human sixth sense.\"

Unlike HPS, most pheromone-fragrance companies operate on the fringe of the retail industry -- you can find their ads in the back of Rolling Stone or on the Web. With names like \"The Dominant Male Collection\" and \"Great Sex in a Bottle,\" they promise everything from success in business to the ability to \"attract women instantly.\" Some are specifically geared toward men or women; others target gay and lesbian audiences. Many boast that they include androstenone, which is a pheromone whose only known effect is to trigger mating behavior in pigs. In April, a newspaper in Santa Barbara reported that one pheromone company, the Body Temple, was sued by a woman who claimed that a man\'s pheromone-enhanced cologne had induced her to sleep with him against her will. The suit was settled out of court; the manufacturer stated that its products were intended only to make wearers feel more confident and attractive, not to act as aphrodisiacs.

HPS is careful not to claim that Realm is an aphrodisiac per se, but it comes awfully close. It says that Realm \"enhances the way we feel about ourselves and how others respond to us.\" And it supports that claim with what sounds like common-sense science. \"Human beings get up in the morning, get into the shower, and scrub all of the pheromones off of their skin,\" says HPS\'s Horgan. \"Then they cover themselves with clothing. So you could say that we\'re pheromonally deprived. Berliner\'s goal was to replenish these pheromones. The first step was isolating them in the skin, then identifying what they did, with human testing. Then trying to bio-equivalently manufacture and synthesize the pheromones, to mimic what the actual pheromones did.\"

The only company to have patented its pheromones, HPS -- known before March 1998 as Erox -- now calls itself the \"world\'s leading pheromone company.\" It no longer runs infomercials. Its current Realm marketing campaign, online and in department stores, has a Picasso-meets-Art Deco look (except for the gold star-shaped stickers on the packaging that trumpet \"Human Pheromones!\"). For the most part, the company sells its perfume through department stores. At Macy\'s, right next to the Tommy Hilfiger and Chanel counters, you can give your wrists a spritz of Realm.

In the $6 billion fragrance industry, Realm is a \"small player with a niche market,\" says Annette Green, president of the nonprofit trade group the Fragrance Foundation. In fact, its sales dropped last year from $17 million to just over $10 million. But, says Green, \"they have a fascinating technology. If they have licensed it to a big player, that could be an important step.\" HPS says it has done just that, although the deal won\'t be officially announced until the fall.

Without a designer name or the marketing clout to create one, Realm is relying on its own science to keep customers coming -- and within the fragrance industry, that seems to be enough. But the scientific community, at least at places such as Harvard and Mass General, is less than convinced.

The idea of a sixth sense has undeniable appeal, and it may well be valid. People probably do interpret and give off subconscious chemical signals. The strongest evidence that pheromones are at work in humans comes from work done by Martha McClintock at the University of Chicago. In March 1998, McClintock showed conclusively that a substance in women\'s sweat can affect the menstrual cycles of other women -- strong evidence for the power of pheromones.

Scientists have known about pheromones for decades, but in recent years, a few researchers have begun the arduous task of singling out and identifying the different elements of the pheromonal system. Among them is Emily Liman, a neurobiology instructor at the Howard Hughes Medical Institute at Mass General. She has been working on pheromone detection since 1992, and on one protein in particular for the past three years.

Liman\'s research focuses on an area inside the nasal cavity called the vomeronasal organ (VNO), a tiny tube full of neurons that is involved with pheromone detection in many animals. She says, \"It\'s been clear for a long time that based on anatomy, the VNO is a separate sense,\" and believes that her recent findings are further evidence that the VNO evolved separately from the main olfactory system. In animals, the VNO picks up chemicals that are otherwise odorless and sends signals directly to parts of the brain associated with emotion and instinct -- sometimes triggering dramatic behavioral changes. In research published in May in the Proceedings of the National Academy of Sciences, Liman, Corey, and Dulac reported that they have isolated part of the pheromonal sensing process: an \"ion channel\" in VNO neurons that seems to play a crucial role in pheromone detection in rats and mice.

For humans, one big question is: do we have this organ at all? The answer may be yes -- sort of. Many people do have tiny cigar-shaped pits in their nasal cavities that are either functional or vestigial VNOs. But the gene that encodes the ion channel is nonfunctional in people -- suggesting that the human VNO is simply out of commission. This is taken for granted by plastic surgeons; nose jobs often block or remove the VNO, so far without any widely reported negative effects.

\"I think it\'s clear that there are some human pheromones,\" says Liman, \"but the perfume companies claim to have identified both a human pheromone and how these pheromones act on the VNO.\" She calls their claims \"debatable.\"

\"We don\'t know the chemicals that are at work, and the other really big unknown is that we don\'t know which cells are detecting the pheromones,\" Liman says. \"We don\'t know if it\'s happening in the VNO or in the main olfactory system, which would be the cells that also detect conscious odors. It\'s very difficult to figure out where signals are being detected, especially with humans, since there are so many problems in doing experiments with humans.\"

Liman recalls a recent conference on olfaction in Belgium. \"Of five scientists working on the VNO, four thought that the human VNO was vestigial. The dissenting opinion belonged to a scientist connected to the perfume company\" (although Liman is careful to point out that majority beliefs are not always correct).

The basis of the claims made by most of the companies that peddle pheromones is slightly opaque; they cite unnamed research and keep their \"pheromone compounds\" under wraps as trade secrets. A spokeswoman for International Flavors and Fragrances, which partnered with Jovan on Andron, confirms that it \"had human pheromones,\" but says that the research that went into Andron can\'t be released because \"it\'s very proprietary information.\"

HPS, by contrast, makes its science public. Asked to produce evidence, Bill Horgan forwarded more than a pound of scientific articles, journals, and newspaper clippings, most of which are papers authored by David Berliner, Louis Monti-Bloch (a scientist who works for one of HPS\'s major investors), and other scientists who have some connection to HPS.

The scientists at Howard Hughes Medical Institute and Harvard and other universities won\'t say that Berliner and Monti-Bloch\'s claims have been proven wrong. But they don\'t seem to take them seriously, either. They say that Horgan\'s materials have not undergone peer review, a standard process in which members of the scientific community evaluate and assess reports in their fields before the reports are published. Horgan says that the articles are peer-reviewed; however, scientists such as Liman, Dulac, and Corey -- who say they are not -- make up a significant portion of the peers who would have reviewed them.

Well-respected names in the olfactory field, such as Liman and Corey, say that HPS\'s science has not been replicated by independent researchers. Horgan\'s primary response to that charge is to invite them to replicate it. But, Liman says, \"No one wants to waste their time trying to reproduce results that they don\'t believe in the first place. If you get a negative result, you can\'t publish it. If their research had more credibility, chances are someone would be trying to reproduce it.\"

Charles Wysocki, an adjunct professor at the University of Pennsylvania, is one of the perfume company\'s more outspoken critics. Wysocki, a researcher at the Monell Sciences Center who\'s been working on the vomeronasal system for 25 years, contributed a chapter to a recent book titled Chemical Communication in Vertebrates (edited by R.E. Johnston, D. Muller-Schwarz, P. Sorenson; Plenum Press, 1999) in which he casts doubt on a number of the perfume company\'s claims. He says he wrote the chapter in part because of \"what appeared to us to be the rather un-objective acceptance of many of the results and the claims that have been made by these groups.\"

If someone has actually isolated a human pheromone and determined how it functions, he says, \"well, they should get a Nobel Prize for it.\"

Wysocki seems to be increasingly frustrated with the claims emanating from HPS. \"You know how many years went into trying to isolate those compounds?\" he says of his and his peers\' research. \"Very few have been identified, and decades have gone into it. There have been literally thousands of bioassays that have been conducted. To just come up with a particular compound or two, or a small handful that you claim are responsible for some pretty amazing behavior in humans . . . and this without a large body of published data . . . that\'s pretty astounding.\"

Even research into various mammalian species that exhibit obvious and dramatic pheromonal behavior historically has been painstaking and time-consuming. If any company has, as HPS claims, synthesized pheromones that can improve people\'s moods and feelings of self-confidence, \"then they got pretty damn lucky,\" says Wysocki.

Liman concurs: if someone had actually figured out exactly how humans communicate on a subconscious chemical level, \"that would be a very big deal.\"

Chances are that the mystery of how and why human pheromones work is a long way from being solved. Apes and humans seem to have evolved in a manner that has, at the very least, diminished the role that pheromones play in the process of selecting a mate. Some might see this as a positive evolution: dating may be frustrating, but it does give us more control than, say, a pheromonal whiff in the dark to tell us that we\'ve found the right gender and species.

But, like miracle diets and aphrodisiacs, pheromonal perfumes will most likely always find a market. A few scientific-sounding terms will probably always be enough to persuade some people to buy these products. And the idea that we can bottle the mysterious convergence of luck, timing, and foolishness that makes for romantic chemistry will probably be eternally appealing.

Meanwhile, until the puzzle is incontrovertibly solved, we may as well go on showering and wearing perfume -- at least for the sake of our conscious senses. When asked whether Realm works, a salesperson at Macy\'s looks perplexed.

\"Well,\" he says, \"I think it works if you believe in it.\"