Buyer Beware Toxicity: FitOldDog Advises, “Don’t Apply Zinc Anywhere Near Your Nose”

I don’t think that it is wise to spray olfactory (sense of smell) poisons anywhere near your nose. Do you? Photo by FitOldDog

These beautiful flowers in our yard smelled so good! Imagine not being able to enjoy their perfume. Photo by FitOldDog.

Zinc has a long and tortured history, as a treatment for the common cold.

“Under the terms of the agreement, 95 percent of eligible plaintiffs must accept the Arizona settlement; the average payment after legal fees would be about $21,000. Zimmerman, who called the settlement “very fair and appropriate,” said the amount would vary depending on the extent of injury determined by medical tests. The settlement does not cover about two dozen claims involving Zicam nasal swabs, which also contain zinc gluconate, or 32 lawsuits outside Arizona. Plaintiffs who reject the settlement are free to pursue their lawsuits, but are likely to have trouble finding a lawyer to represent them.” Paying Through The Nose, Sandra G. Boodman, 2006

Very fair and appropriate? Really? Zinc had been known to be an olfactory toxin for about 60 years!

“Buyer Beware Toxicity: Always read the package insert and, if in doubt, don’t spray anything near your nose.” Nasal Toxicology Expert, FitOldDog.

Jack’s lovely meal of egg plant, chicken gizzards and hearts, squash, shrimp, duck, and rice (not shown). Yummy! Smelt so good. Imagine not being able to smell your food!

Many years ago, as a result of my publication record, I was invited to speak at a pathology meeting on sensory toxicity, concerning poisons of our various detection systems, including the sense of smell (olfaction). It was a morning symposium, with four one-hour lectures, each addressing a different major sensory system, including vision, hearing, and touch, plus my lecture, the sense of smell. I can’t recall if gustation (sense of taste) was addressed, but I do remember the response I received, from an audience of about 500 toxicologic pathologists of all ages, male and female, to the following questions that I posed at the beginning of my lecture:

How many of you have had your eyes tested? All hands raised.

How many of you have had your hearing tested? All hands raised.

How many of you have had your sense of smell tested? One hand raised, by an older guy, in the far left corner of the room. I doubt the numbers would be much increased today.

If you lose your vision or hearing, the effect is immediately obvious. With the sense of smell, it is less obvious, but there is still impairment of your quality of life, with respect to the enjoyment of cuisine and perfumes, and safety when it comes to detecting noxious gases or food that is spoiled. But we are not routinely tested for dysmosmia (impaired sense of smell) or anosmia (loss of the sense of smell). Layer on top of this the considerable variance of people’s odorant ‘rainbow.’ Some individuals can detect ketones, as in your breath when sick, remarkably effectively, but are almost blind to indoles, as in dog feces (e.g. FitOldDog), whilst other people can have exactly the reverse sensitivity spectrum (e.g. Deb). It is not so easy to test your sense of smell reliably, because one odorant is not suitable for all, though systems do exist.

Radium treatment in 1940, reproduced with acceptance of the open use license, at this link.

The evening following the lecture, I was enjoying a beer in a bar and happened to sit next to the very same guy who raised his hand. I didn’t recognize him, but he recognized me, so I asked him his story. He explained that he was a pilot in World War II, but he had a badly stuffed up nose at the time, which could be a problem with air pressure changes in the cockpit. So, they inserted a lump of radium up his nose, and after that he could breathe fine. The radiation killed a bunch of cells up his nose, making more room for airflow, but it also killed most of his olfactory neurons (nerve cells responsible for the sense of smell). His sense of smell was completely, and permanently, destroyed by the radium treatment, he said.

Well, it turns out that zinc is an equally dangerous olfactory toxin.

When I saw an over the counter product in the grocery store today, Cold-Eeze, containing zinc gluconate, designed to be sprayed in your mouth, that is, near your nose, for cold relief, I was immediately concerned.

Quote by Matrixx, justifying a new product, based on expected intra-nasal disposition of a modified formula. Oh! Boy! Did they understand nasal airflow, and local shear forces near the valve?

This compound, zinc gluconate, can ruin people’s sense of smell. So I researched it, and found that there were, in fact, a number of old lawsuits addressing this very issue, and then I found the quote in the adjacent image, related to a modified version of the product, implying that this removed the safety concerns for the intra-nasal product.

I thought, “That’s not going to work, what with the shear forces in and adjacent to the nasal valve, they must be joking.”

Finally, I was pleased to find that the nasal spray had been withdrawn from the market, but does that mean we are safe from zinc as an oral spray?

I’m not so sure!

If you inhale through your mouth, and don’t hold your nose closed, you are actually breathing oronasally, with about half of the air going through your nose.

An excellent book, though very dark, that gives you a chance to think about a world seen through the sense of smell (like our dog, Willbe).

If you simultaneously spray a mist into your mouth, I suspect that a significant amount of the spray could enter the nose, putting the olfactory mucosa at risk. That is my concern with this Cold-Eeze. Even if you instruct people to clamp the nose shut when they inhale the spray, how many are actually going to do it. Furthermore, some people might spray the stuff up their nose, anyway.

Surely there are better ways to approach the common cold than with inhaled zinc?

Anyway, about two weeks after the lecture a surprise package arrived at our home. It was a kind gift from one of the other lecturers in the session, Dr. Phemister, I think, and it contained a sinister novel, all about the sense of smell, Perfume, The Story of a Murderer, by Patrick Süskind. What a kind thought, I thought.

See, scientists are people, too!

Your nose is an important and delicate piece of machinery, upon which your full enjoyment of life very much depends, so look after it, and think before you spray.

Kevin T. Morgan (aka FitOldDog), BVSc, PhD, Diplomate ACVP, Nasal Toxicology and Pathology Expert of many years, with considerable knowledge of nasal biology, including nasal airflow – I put that in there to try to convince you that I know what I’m talking about.

PS Our yellow lab, Willbe, says that he is very concerned about zinc out there in the world, as he loves to sniff!