The Stanley Cup Lead Scare Is Not Something to Worry About, Experts Say

You might have heard of the Stanley tumbler, the hip, trendy water bottle that has people camping outside stores or getting into fights to get their hands on one.

They’ve become a fashion accessory, especially since Stanley has made use of influencer culture to target women and make sales of its tumblers skyrocket. The reach of the bottles has been amplified by social media users.

But social media giveth and social media taketh away. In recent weeks, several widely shared posts on TikTok, Instagram, Reddit and X have amplified concerns Stanley cups may contain lead, with one X user calling it “The Leadening.” YouTubers have also jumped into the fray. One TikTok video on the topic was viewed nearly seven million times.

Some Stanley owners, hoping to check the claims, started to use home lead-testing kits, which experts say are not reliable. A sendup of the Stanley cup phenomenon on “Saturday Night Live” over the weekend — a sketch called “Big Dumb Cups” — even mentioned the lead in passing.

The lead discussion has popped up on Facebook comment sections, as in one group with more than 61,0000 members called “Stanley Cup Hunters + Drops” — for “passionate Stanley Cup fanatics.”

One person wrote, “If we want to dress up our lead cups with a flower straw cover and a glitter boot and show them off, lets us be!! We know they have lead, you have told us. We don’t care!”

So you might be wondering: Do I have to throw my Stanley cup into the fireplace? (No. In fact, don’t throw anything into your fireplace.) We have some answers for those of you who really want to keep up with the times and drink water fashionably.

Yes, according to the company’s website. It says that its “vacuum insulation technology,” which keeps the cup’s contents at an ideal temperature, uses “an industry standard pellet to seal the vacuum insulation at the base of our products.” The sealing material, it says, “includes some lead.”

Once the bottle is sealed, Stanley said, the area is covered with a layer of stainless steel, which the company says makes the lead “inaccessible to consumers.”

No. Almost assuredly, no.

Jack Caravanos, a professor of public health at New York University who studies lead, tested three Stanley cup models of different sizes on Monday using an X-ray fluorescence detector, which determines the elements of a material.

“There’s a lot of places where lead can be on a cup like that,” Dr. Caravanos said. “It could be on the inside, the outside, the labels, decals. And, I did not find lead — sort of superficial lead on the surface — in any part of the cup.”

“I’m a global exposure expert,” he added. “I’ve done a lot of work in different products and countries. And the threat to human health is really negligible because you’re not going to really put your mouth anywhere near that surface, and it’s not going to readily dissolve into anything that can get into you.”

But what about the area underneath the stainless steel?

For that, Dr. Caravanos said he would have to deconstruct the cup itself — by no means an easy task.

“I tried repeatedly to pry open the bottom cap with various tools and failed,” he said. “Perhaps the lead is being used to seal the cap closed. In any case, it should further assure the public that lead material is very unlikely to ever be released from the cup and be made available for ingestion.”

Dr. Caravanos said that at-home lead tests on the market today are not considered reliable — and none of them available today are approved by the Environmental Protection Agency. Though on Tuesday morning, Dr. Caravanos tried an at-home test on a tumbler and still did not get a positive test.

That the cups use any sort of lead to begin with showed “poor thinking” on the part of the company, Dr. Caravanos said.

I’m really disheartened and sort of angry that a company like this uses a known toxic ingredient that is banned in many applications for a cup,” he said. “I mean, surely there could have been an alternative.”

A Stanley representative referred to the explanation on the company’s website describing the use of lead in the cups. But in a statement to NBC News, a representative said, “Our engineering and supply chain teams are making progress on innovative, alternative materials for use in the sealing process.”

Lead, which is regulated by the federal government, is still prevalent in the United States, particularly in paint, cookware and water that travels through lead pipes.

“There are many health effects associated with lead exposure, such as reproductive toxicity, cardiovascular disease,” said Maria Jose Talayero, a public health researcher at George Washington University. “And the one that I study the most is the damage to the nervous system, which results in a variety of neurological effects.”

She added, “But it’s a fact that other cups and other manufacturers do not use lead, so why have it in there in the first place?”