Smell, most intimate of senses

Press, 10 January 1987, Page 24

Smell, most intimate of senses

Washington! "Odours reach into our emotional life, drawing from the deepest caves m our minds," Boyd Gibbons wrote in the September issue of the magazine, "National Geographic.” Of all the five senses,, smell. is the most Intimate, the most underrated, and the least understood. "We think our lives are dominated by ottr visual sense,” says Gordon Shepherd, a Yale neuroscientist, "but the closer you get to dinner, the more you realise how much your real pleasure in life is tied to smell. It taps into all our emotions. It sets the patterns of behaviour, makes life pleasant and dis-, gusting, as well as nutritious.’” Gibbons recounts the stirring of vivid memories of his late grandfather, evoked' solely from an impulsive, sniff of the man's old deerskin hunting vest. "Such is the involuntary power of the. sense of smell, my boyhood was recalling me,” he writes. NUANCES OF SNIFFING All nuances of flavour come from sniffing aromas* < or exhaling them as we .drink or chew food. “Most of the identification of wine is in the nose, and the taste is only confirmation,” a French vineyard owner told Gibbons. To enjoy its full benefits, he slurped and gurgled it, sending its aroma up the back channel to his nose. Over millennia dating back at least to the ancient

St. Helena, scented smoke from burning pellets suffused his room. Today, only a few of the old Paris perfume houses still make their own perfumes. More common than the classical independent perfumers are chemical wizards such as Bernard Chant, chief perfumer for Inter- . national Flavours and Fra- , grances of New York City, the world’s largest company of its kind.

Egyptians, people have used perfumes to improve the way they and their environment smell. The Egyptians 4500 years ago sniffed aromatic smoke from frankincense and myrrh. They burned Incense to please their gods. Their pharaohs* bodies were embalmed with fragrant spices. At early Roman banquets and orgies, the fluttering of perfumed white doves scented the air. Rose water helped raise the Roman bath to its apogee of sensuality. With the rise of Christianity, the church banned public baths. Yet even in the Middle Ages the rich'wanted their perfumes, if only to obliterate odours of the lower classes. Perfumery gradually rose to new heights of sophistication. Napoleon drenched himself with eau de Cologne. As he lay dying on the island of

The company creates everything from perfumes to flavourings for taco chips. On any day, Chant may be working on fragrances for clients’ products as diverse as shampoos, colognes, or plastic trash bags. SHOPPING BY SCENT Large soap companies are the biggest users of fragrance; one brand uses more than 2 million pounds of scent each year. “Fragrance is the strongest drive in consumer soap preferences,’’ an executive of a major soap company told Gibbons. “Among all the attributes, I would probably rank performance at the bottom.** Men and women alike spend a great deal of time and money suppressing body odours, which are the smell of acids produced by bac-, teria metabolising skin secretions. The most repellent odours come from the apocrine glands, associated with underarm and genital hair and activated when people are frightened, excited, or aroused. In the days before modern medicine, physicians de-, pended on their noses to help diagnose illness. Typhoid smelled like baking bread, German measles like plucked feathers, scrofula like stale beer, yellow fever like a butcher shop. Some 2 million Americans suffer from anosmias, disorders of smell, .but medical textbooks offer little guidance for treatment. Some anosmias are genetic, but most result from head injuries, viral infections, allergies, ageing, or nasal obstructions.

Most animals have far more sensitive noses than do humans. They put them to good use. Because they have to protect themselves against' being poisoned, animals' rarely touch food that smells like something that once made them sick. Natural odours that induce all manner of psychological or behavioural changes in a species are called pheromones. Nowhere do pheromones have a more profound effect than among insects, who use the odours to organise . their complex societies. Salmon may roam thousands of miles at sea, then return to the river of their birth and swim upstream, following an odour imprinted years earlier. TERRITORIAL ODOURS By defecating, urinating, and marking with scent glands, mammals maintain their territories and identify each other. They use odours to give alarm, to select food, and as an integral part of mating. Beavers keep strange beavers out of their neighbourhoods by strategically depositing smears of a substance called castoreum. Thomson’s gazelles mark their territory by depositing tarry stuff from glands beneath their eyes. Reindeer have scent glands behind their hind toes. Rabbits

mark with chin glands. Cats rub against people with their eyebrow and rump glands. Dogs’ acute sense of smell ■ makes them useful for sniffing out everything from

drugs and bombs to termites and iron ore. Or tracking down fugithe thrill of hunting a man, Lanson Newsome, warden of the Georgia State Prison,

told Gibbons. “I’ve pulled a dog off a scent, thinking the man went this way or that, the - 8 was almost always right. —Copyright National Geographic News Service.

Allofthe nearly 11 million members of the National Geographic Society have a chance to participate in a scientific scratch-and-sniff survey. . The smell survey, described by Wilbur E. Garrett, editor of “National Geographic” magazine, as “the world’s largest scientific test ever conducted,** took 18 months to prepare. The work was done in cooperation with the Monell Chemical Senses Center of Philadelphia, whose scientists will help evaluate the results. The survey is printed infoldout brochures inserted in the magazine’s September issue. Each brochure contains six scented panels. The carefully chosen scents were donated by two major fragrance companies, Firmenich SA of Geneva, Switzerland, and International Flavors and Fragrances of New York City. Garrett sees the survey as an opportunity to make a significant scientific contribution to the understanding of smell. “It’s the least-understood of our senses, and one of the most critical,” he says. One specialist told Garrett that as many people suffer from smelling deficiencies as wear glasses. “You may have a 20-20 nose or you may have a blind nose, but there are no simple ground rules for testing,” Garrett says. “There is no equivalent of the eve chart for the nose.” In preparation for the survey, says Robert W. Hernandez, director of the project, consumer panels at shopping malls around the country tested prospective odors. The survey accompanies a 38-page article, “The Intimate Sense of Smell,” by Boyd Gibbons of the National Geographic staff.

'Fragrance is the strongest drive in soap preferences*