Are Stanley Cups Potentially Harmful Due to Lead Content?

The Stanley tumbler range is making headlines, not for its popularity on social media but for the nominal amount of lead present in the cups.

TikTok users have been revealing that Stanley tumblers contain lead using lead test kits, causing anxiety amongst numerous individuals who drink out of these widely-used cups.

Although it is correct that Stanley tumblers have a small proportion of lead, the manufacturers assure that these cups are secure and neither the consumers nor the drinks ever interact with the lead.

"On the surface of any Stanley product that interacts with the consumer or the product's contents, there is no lead," Stanley asserted on its website. "Stanley guarantees that all its goods meet all USA regulatory standards." Stanley and its parent company, PMI, were contacted by Health for additional comments, but there was no response at the time of publication.

Regardless, the thought of drinking from an object containing lead on a daily basis can be disconcerting. Here’s more information about the lead in Stanley tumblers, the consequences of lead poisoning, and things to consider if you're considering a new water bottle.

In brief, yes. As revealed in a statement on Stanley’s website, the lead is involved in the cup's vacuum insulation technology, which keeps the beverages at the perfect temperature.

"A industrial standard pellet is used in our manufacturing process to seal the vacuum insulation at the product base; the sealing material includes some lead," the company explained. "Once sealed, this area is covered with a strong stainless steel layer, making it inaccessible to consumers."

Yet, Stanley cups are not the only items that include trace amounts of lead.

"We are aware that other brand products using the same lead vacuum seal have been recalled in the past—some as recently as November 2022 because the lead solder at the cup bottoms became accessible," highlighted Olga Naidenko, PhD, VP for science investigations, research, and development at the Environmental Working Group, a nonprofit that investigates pollutants and chemicals in consumer goods.

The revelation has also led to other tumbler and water bottle makers speaking out against the use of lead in products.

Hydro Flask, a water bottle maker shared on Instagram "A lot of conversation is happening as of now about lead. We assure you that Hydro Flask does not use lead in our vacuum sealing method. In fact, more than 10 years ago, we pioneered a new process that sealed our bottles without using lead."

Though lead is naturally occurring, it can be toxic to both humans and animals. Lead exposure at any level is harmful, and children are particularly susceptible to the harmful effects of lead, as they absorb more lead than adults when exposed, Naidenko states.

Calello, MD, executive and medical director of the New Jersey Poison Control Center at Rutgers New Jersey Medical School, revealed to Health that "Lead exposure during childhood can result in academic, behavioral issues for children as it impacts the developing brain. Generally, this is a result of deteriorating paint in their homes over a long duration."

Naidenko further states that homes constructed before 1978 may still contain lead paint and lead was more commonly utilized in children's toys- though the Conservation Product Safety Improvement Act of 2008 has tightened government regulation of lead in toys and other products. Vintage or foreign toys may still contain lead.

Adults too can be exposed to lead via occupational and environmental situations- for example, people can inhale lead particles when lead-containing materials are burnt during smelting or ingest lead-contaminated dust or consume water from lead pipes.

Products found to contain unsafe lead amounts are usually recalled. Like the recent recall of some cinnamon apple sauce products by the Food and Drug Administration(FDA) as they were found to contain lead. Lead exposure can lead to serious health problems such as increased blood pressure and issues with brain, kidney, and reproductive health.

Lastly, as long as the cup is not damaged and used as recommended, the lead in the cup presents no risk.

“It’s not immediately dangerous to life and health, just being in the vicinity [of lead],” said Calello. “If the cup is used properly, it should not pose a lead hazard.”

Stanley maintains this as well, assuring customers in their public statement that lead isn’t present on the surface of any Stanley cups and that it never comes into contact with the consumer or anything they may ingest.

To that end, the company said that the base cap of a product ever does come off—potentially making lead exposure possible by exposing the seal—the cup is eligible for a Lifetime Warranty to be replaced.

But some experts say young children may want to opt for other drinking vessels.

“When it comes to products that are used for or around young children, it is not worth taking chances with lead because it’s so toxic,” said Naidenko.

While you can drink out of your intact Stanley tumbler safely and without worry of lead poisoning, if you’re in the market for another, some experts recommend looking for an option that doesn’t use lead in its manufacturing process.

“We recommend that consumers look for water bottle options that don’t use lead in their products,” said Naidenko. “It’s unacceptable that people, especially young children, may be exposed to lead—a powerful neurotoxin—because of using a cup or any other consumer products, [and] we know the use of lead is avoidable based on…statements from manufacturers who find alternatives to lead for vacuum sealing their products.”