When it comes to fragrances, what's aromatically awesome to one person is absolutely awful to someone else. Scents can make many of us sick.
Smelly differences of opinion in recent years have spawned everything from workplace, hospital and school bans on perfume, body spray and deodorizers to lawsuits claiming scents created a hostile work environment.
Last month, a Bethlehem, Pa., high school asked students to cut back on using Axe Body Spray after one student had to be hospitalized from a reaction to the popular teen scent. In 2010, Detroit officials told city workers to curb use of perfumes and heavily scented deodorants after one employee claimed severe perfume sensitivity and won a $100,000 judgment in federal court.
For millions of people, the smell from a perfume, household cleaner, shower gel, body lotion or detergent can produce reactions ranging from sneezes and watery eyes to migraine headaches and difficulty breathing.
"Fragrance sensitivity is actually much more widespread than many people recognize," said Dr. Alan Hirsch, head of the Smell & Taste Treatment and Research Foundation in Chicago.
One analysis published by researchers at the University of West Georgia in 2009, based on surveys of more than 2,100 people between 2002 and 2006, found that 30 percent of respondents thought that scented products worn by others were irritating and 19 percent experienced adverse health effects from the exposure.
Results from a network of dermatologists in Europe, cited by the International Fragrance Association, indicate about 2 percent of the general population suffers from fragrance allergies on the skin.
Fragrance ingredients are largely unregulated and untested for most products. Researchers estimate 4,000 chemicals are used in giving odor to consumer goods, 95 percent of them derived from petroleum, according to a report from the National Academy of Sciences.
"The range of products with scents has certainly exploded over the past few decades, and for many people, that produces a real sensory overload," said Pamela Dalton, a psychologist and olfactory researcher at the Monell Chemical Senses Center in Philadelphia. "The trick is figuring out which of hundreds of chemicals in a fragrance or the product with the fragrance is responsible for our reaction."
Hirsch and others note that while people are exposed to more aromas, our sense of smell has also likely improved as secondhand smoke and many types of pollution have been curbed.
Dr. Jonathan Bernstein, a Cincinnati allergist, researcher and professor at the University of Cincinnati College of Medicine, said reactions to fragrances are "very common" for people in his clinic and seem to be becoming more prevalent.
"We treat a lot of patients with asthma and allergic rhinitis who are challenged by exposure to certain fragrances, but there's a larger group who have an array of nonspecific reactions that are poorly understood and more complex to treat. We don't understand why some are susceptible and others are not."
Dalton said many people may have a psychological reaction to a scent. "They don't like the way something smells and they resent the loss of control over their personal environment," she said. "Reactions to a scent may also be stronger if you don't like the person who's wearing it for other reasons," Hirsch added.
It's not clear whether what a person smells is actually responsible for symptoms. "A lot of products have ingredients like ammonia or alcohol that can cause reactions, but because we smell the fragrance, we assume that's the irritant causing us to sneeze and get watery eyes," Dalton said.
Many places have turned to blanket bans on personal scents because it's hard to set a threshold for what offends. Men generally have a poorer sense of smell than women; different ethnic groups may smell certain things differently; people tend to have a reduced sense of smell as they age.
Bernstein and Dalton agree that fragrance sensitivity may ramp up for people with seasonal allergies. "If you're already suffering from the pollen, you may be more sensitive to irritants indoors, too, things you might not notice other times of the year," Dalton said.
She added that it is impossible to eliminate or avoid all scents. "You need to do a little detective work and confirm what's really bothering you, what triggers you and when."
Hirsch noted, "Just because something smells bad to you doesn't mean it's dangerous. But if you're getting headaches, shortness of breath, rashes, then you should take it seriously and come up with a plan to avoid that product or products."