KANSAS CITY, Mo. — Gladys McGlon is a retired nurse practitioner, so traveling to see her grand kids is one of her favorite pastimes. In April, she was on her way to do just that.

“I love those kids, I love going to Atlanta.”

But Gladys almost didn’t maker her flight. While going through security at KCI, she was randomly checked for traces of explosives. Boom. TSA had a “hit” and Gladys found herself pulled aside for the pat-down.

“What are you looking for?” she asked the agents. She said they couldn’t tell her other than, “the machine says you have trace evidence of an explosive.”

Reluctantly, and facing a deadline to board her flight, Gladys agreed to what she describes as a very aggressive pat down.

“I felt like I was a victim. I was guilty.”

When she got to Atlanta, she had a hunch. The trace had been picked up on her hands, and she had applied a hand lotion before leaving her Lee’s Summit home.

So she called the product maker, L’Oreal. Before she could finish her question, the woman at the consumer hotline had the answer.

“She knew right away and told me it’s the glycerin in the product.”

That’s right. Glycerin. The same compound used to make explosives is also a moisturizing agent, and in the CeraVe that she applied before flying.

“First time I’d ever heard of that,” she sighed.

She’s not alone. It was a first time for many of the passengers we talked to at KCI on a recent afternoon.

But the TSA said glycerin and nitrates are among the trace elements its indicators look for. The agency declined to name others, but admitted in rare instances, these items found in home products and fertilizers can trigger its equipment, requiring a secondary screening.

It has happened in other markets too. In fact in St. Louis last February, a woman visiting a farm exhibition had traces of explosives in an arm cast she was wearing, and was denied boarding until she had it removed and replaced. The Virginia woman eventually made it home, but only after returning to a hospital and having a new cast applied to remove the likely farm nitrates that triggered her screening.

Experts advise avoiding moisturizing products that contain glycerin, and avoid handling other products like baby wipes, some cosmetics, soaps, and even medications that can contain triggering ingredients.

In a statement, the TSA said the instances are rare, and that normally a quick pat down clears the passenger to fly.

Gladys did make her flight and enjoyed her time in Atlanta.

“I totally understand the political moment we are in right now in the world and country,” she said, but remains frustrated she wasn’t given much information about why she’d triggered the secondary screening.

In the future, she’ll stick with Vaseline to moisturize when she flies.

Probably a good idea, since in a statement, L’Oreal said it has no intention of reformulating its products using glycerin.