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Scents and Sensibilities

By Jeffrey Kluger
Jun 1, 1996 5:00 AMNov 12, 2019 6:38 AM


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I don’t know if my friend Dan Curry is still making his garlic meatballs, but I hope he isn’t--and I’m sure the Environmental Protection Agency feels the same way. It’s not as if I didn’t enjoy Dan’s garlic meatballs; the problem was, Dan’s garlic meatballs weren’t garlic meatballs at all but something closer to vaguely meat-flavored garlic balls, with each ball made up of approximately three molecules of meat and the rest pure garlic. Dan didn’t whip up his signature dish any old time, but generally saved it for especially important Sunday afternoons when he and a few friends would get together to watch an especially important sporting event on TV. Of course, Dan’s definition of an especially important sporting event was a bit looser than most people’s, including everything from Super Bowls and World Series to hockey playoffs, luge finals, tractor pulls, taffy pulls, and round-robin quilting.

For a time I participated enthusiastically in these gatherings, but after a while I began to wonder if they were such a good idea. On the Monday after a meatball Sunday, I found that I often had something of a breath problem. And I don’t mean the kind of problem that responds readily to a swish of mouthwash. I mean the kind of problem that threatens to strip paint, defoliate parks, and cause canaries in the vicinity to request work in the nearest coal mine. Worse, the condition tended to linger--six months later complete strangers would still be coming up to me on the street and asking, You been watching luge finals with Dan Curry or something? Dan’s meatballs, I began to realize, had less a shelf life than a half-life, and if I hoped to have a social life, I knew I’d better cut down.

Eating garlic meatballs, of course, is not the only way the usually scentless can suddenly begin knocking their friends senseless. There are countless things--from alcohol to the common cold to more serious problems like kidney disease--that can turn even the fairest breath foul. Just what causes your own personal air quality index to move into the red zone is your business; moving it back into the green is Dr. Jon Richter’s.

Richter is a periodontist in central Philadelphia who, besides such comparatively safe D.D.S. practices as cavity filling and tooth drilling, specializes in the somewhat riskier business of breath freshening. Head of the straightforwardly named Richter Center for the Treatment of Breath Disorders, Richter has established himself as one of the country’s leading experts on breath, acting as a sort of court of last resort for people whose breath problem is severe enough to have defied traditional remedies. Interested in seeing how so unlikely a specialist plies his trade--and more than a little concerned that after years of meatball abuse I might be in need of his services myself--I decided to pay the clinic a visit.

The first thing I learned about making an appointment with a breath specialist was that it is not something to be undertaken lightly. When I got Richter on the phone, he warned me that for his breath- assessment tests to be as accurate as possible, he preferred to examine mouths in as pristine a state as possible. Pristine, in this case, means unbrushed, and in the case of most mouths I’m familiar with, that means trouble.

In an animal kingdom in which creatures have developed everything from fangs to claws to quills with which to protect themselves, there may be no more effective natural defense than morning breath. Most predators given a choice between attacking, say, an enraged boar in the middle of a charge or an early hominid in the middle of a nap would not hesitate to give the protohuman a protopass. For most modern people, the idea of leaving the house in the morning without a vigorous toothbrushing is all but unthinkable--at least not without applying for a relaxation of federal emissions standards--but this was exactly what Richter was suggesting I do. Despite this, there were a few unanticipated advantages to this plan, notably that the train I planned to take from New York to Philadelphia was usually a crowded one; under the circumstances, I suspected I’d have the entire car--if not the entire northeast corridor--largely to myself.

Happily, I found the journey uneventful, and when I arrived in the waiting room of Richter’s office, things seemed similarly unremarkable. Despite the presence of three other patients also presumably waiting for breath assessment, I noticed nothing untoward: a chance yawn did not seem to trigger building-wide sprinkler systems; hygienists were not dressed less for dental work than for Three Mile Island exposed-core cleanup. Things changed, however, when the receptionist handed me a form that she requested I fill out. Labeled Halitosis Psychological Impact Questionnaire, the survey, part of a study being conducted by Richter and the psychiatry department at the University of Pennsylvania, was intended to pinpoint where I fell on Richter’s own Richter scale, and the questions were unflinchingly candid.

How much have problems with your breath interfered with your ability to function at work? one asked. How much have problems with your breath interfered with your social life? Some questions had special relevance for me, given how I felt about my own breath at that moment. What makes you think you have a breath odor problem right now? asked one particularly apt one. (You mean apart from the fact that the receptionist used fireplace tongs to hand me this form?)

Once I had completed the questionnaire, I and my breath were handed off to a dental assistant--an apparently fearless woman named Khempeth Chanthavanh. Ordinarily, I would try to initiate conversation with someone whom I’d be working with in such close medical quarters. But with Chanthavanh’s name such a polysyllabic mouthful, and my mouth such an unpleasant place to be at the moment, I simply nodded and let her show me to an examining room. There, she got straight to work, uncovering a small machine known, appropriately enough, as a Halimeter. The Halimeter could have been mistaken for a lie detector except that it had what appeared to be a flexible drinking straw protruding from the front.

This machine is designed to measure volatile sulfur compounds, Chanthavanh explained, since sulfur compounds are almost entirely responsible for the odor associated with bad breath. I need you to keep your mouth closed and breathe only through your nose for three minutes. Then slip this straw into your mouth and hold your breath.

I did as Chanthavanh requested and watched the Halimeter pump the accumulated air from my mouth, curious whether the needle would jump off the scale. To my surprise it barely moved. Either my unbrushed breath wasn’t nearly as bad as I thought it was, or the machine was still calibrated for the previous patient and that patient had been Puff the Magic Dragon. Chanthavanh, however, seemed unmoved, made a few notes in my chart, and gave me my next instructions. This time the Halimeter was replaced by a deflated plastic bag with an attached straw. Okay, Chanthavanh said. I want you to insert this straw in one nostril, cover the other nostril with your finger, and exhale.

Now, I admit I’m not trained in these matters, but if I had a halitosis problem so severe that my nose had acquired my mouth’s breath, don’t you think I would have known by now? Besides, even if that were the case, what could be done about it? I don’t care how experienced the folks in Richter’s office are, sticking two breath mints up my nostrils before social engagements was not the kind of prescription I came here to get. But again I suppressed my doubts. After I’d exhaled, Chanthavanh attached the bag and straw to the Halimeter, and again the machine registered unremarkable results.

The rest of the exam proceeded undramatically, with Chanthavanh requesting a few more Halimeter readings, taking a couple of tooth and jaw X-rays, and actually asking to smell my breath herself (Open your mouth and say ‘Ahh,’ she said, moving in for a whiff as I waited to see if she would open her eyes and say Oy!). Only after this last test did Richter himself finally appear. His belated arrival took me a bit aback. No rule says that the boss has to assume all the workplace risks, but when your clientele consists of people who could legally be forbidden to exhale in the state of California for fear of breaking catalytic converter laws, it seems unchivalrous to make your employees meet them first. Richter, however, appeared less concerned with workplace etiquette than he did with the business at hand, and after introducing himself and glancing at my chart, he started right in.

There are two things that can cause bad breath, he explained, systemic problems and localized bacterial infections of the airways. Systemic problems are less common and more serious and involve any disorders that cause certain volatile substances to accumulate in the bloodstream. These then pass through the lung wall and are expelled into the air when the person exhales.

A number of disorders can lead to this phenomenon, and among them are kidney and liver diseases. These illnesses compromise the body’s ability to rid itself of hydrogen sulfide and methylmercaptan. As chemists know, both of these compounds include generous amounts of sulfur; and as chefs know--or at least chefs who have inadvertently cracked open a rotten egg--the smell of hydrogen sulfide is not a pretty thing.

Excess sulfur compounds have to go somewhere, Richter said, and where they go is the blood first, the lungs second, and the air last. If the problem is coming from your lungs, the only real solution is to treat the illness that’s causing sulfur compounds to build up.

It’s not only disease, though, that can cause chemical levels in blood to rise and local atmospheric conditions to fall. As it turns out, alcohol can, too--a fact that is painfully obvious if you and a friend have ever had a few too many drinks and then leaned in close for an intimate conversation (It’s quarter to three; there’s a reason there’s no one in the place except you and me). And if alcohol can linger in the blood, garlic--whether in a meatball matrix or not--moves in, sets up house, and signs a long-term lease.

In the case of garlic, Richter explained, the problem is caused by several mercaptans that enter your bloodstream as the garlic is digested. In the case of alcohol, it’s straight ethanol that’s responsible. Both substances are highly volatile and carry distinctive smells.

While systemic breath problems take time to resolve, not all halitosis is so hard to treat. Far more responsive to quick fixes is bad breath whose source is the mouth itself. More than 90 percent of cases of bad breath originate in the mouth, Richter said, and practically all are caused by bacteria.

The human body is home to thousands of species of bacterial life, the majority of which are known as aerobic bacteria. For most people the term aerobic bacteria conjures up a not entirely scientific image of millions of microbes attractively outfitted in tiny leotards and pseudosneakers for their pseudopods (Feel the burn, bacilli!). The aerobic label, however, describes not how microbes exercise but how they metabolize. Aerobic bacteria, Richter explained, process energy much the way humans do, by using oxygen to break down carbohydrates, which provide energy to cells and release carbon dioxide and water.

Slightly less numerous than aerobic bacteria are anaerobic bacteria, which break down their food without the assistance of oxygen and prefer a menu made up of proteins rather than carbohydrates. Proteins are chains of amino acids, some of which contain sulfur--with its highly unwelcome tendency to form volatile, and hence smelly, compounds with other elements. As some anaerobic bacteria metabolize a meal, they release copious amounts of sulfur compounds as waste. When that release takes place in your mouth, it’s not long before the world learns about it.

What you’re smelling when you smell someone’s bad breath, said Richter, is usually nothing more than the waste product of certain communities of bacteria that make the mouth their home.

I was not pleased to learn this fact. If my body is going to be serving as communal housing for millions of microbial tenants, I’ll determine where the rest rooms are, thank you very much--and the place they picked ain’t it. I’ve long accepted that sailors are merely using a figure of speech when they say they have to go to the head, but suddenly I find that when it comes to bacteria, the head they’re talking about is mine. The problem, Richter explained, is that the mouth--with its warm, moist, protein-rich environment--is such a hospitable breeding ground for anaerobic bacteria, and almost everything we do seems to make it more so.

When you keep your lips closed and breathe only through your nose, Richter said, you lower the oxygen level in your mouth, encouraging the growth of organisms that need no oxygen in the first place. Conversely, if your nose is congested and you breathe only through your mouth, oxygen levels rise and it is the aerobic bacteria that bloom. As soon as you lay down a plaque of aerobics, however, anaerobics take hold in the oxygen-poor region just beneath them.

There are a lot of places in the mouth that anaerobic bacteria like to homestead, including tiny gaps between teeth that may show up only on X-rays, and, especially, the back of the tongue. If there’s a gold coast in the real estate market of the mouth, the back of the tongue is it, so it’s here that Richter looks first when he’s on the trail of a breath problem. I asked Richter how my tongue looked, and with some relief I learned that the Halimeter readings and a simple visual exam revealed neither the bacteria’s telltale odor nor their telltale coating. But what if I hadn’t come up so clean?

For patients with a heavy load of anaerobic bacteria, Richter said, we recommend a two-step procedure known as oral debridement, which includes irrigation. Debriding involves mechanically removing the anaerobic plaque from the mouth with a tool that gently scrapes the tongue. Irrigating involves the use of a high-pressure stream of a chemical irrigator containing chlorine dioxide and water. The irrigator dissolves the sulfur compounds produced by the anaerobic bacteria, destroys the proteins they feed on, and increases overall oxidation potential, making the environment inhospitable for more of the bacteria to grow. For most high-fragrance patients, only one or two office visits are necessary to get the initial breath-freshening work done, after which they can handle the job on their own with a simple plastic scraper and a few bottles of the deodorant mouthwash.

Fortunately for the majority of people, even these relatively benign measures are not usually necessary. Simply by brushing the teeth and the back of the tongue twice a day, flossing regularly, and using over-the- counter mouthwashes, one can keep most oral effluvia under control. Indeed, Richter informed me that this was probably all the attention my own breath needed--though with the morning almost gone and my teeth still untouched since the night before, we both agreed it needed it bad. Even after a vigorous brushing, however, I realized that my worries were not permanently over. Knowing what I now knew about the chemistry of breath, I understood that try as I might, nothing would help the next time I found myself with a craving for something like garlic meatballs. On those occasions, I would have a choice between resisting the urge and yielding to it, understanding that for at least 24 hours I could have either my meatballs or my loved ones, but I couldn’t have both.

Anyone know what time the next tractor pull is on?

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