Stanley Quencher cups are a viral sensation, becoming a must-have staple amongst social media influencers. The reusable 40 oz tumblers are hailed as environmentally-friendly and stylish. According to Stanley’s website, they can keep hot drinks warm for at least seven hours, and cold drinks cool for at least 11 hours. In 2023, as the product grew in popularity, the company made $750 million in revenue, ten times the $75 million revenue it made in 2022.
But all that attention has also brought more scrutiny to the product. TikTok users and other social media influencers have been testing the tumblers for lead, with some claiming that the results showed lead was present in the cups.
Lead can be harmful if ingested, particularly in children younger than six, notes the Centers for Disease Control and Prevention (CDC), adding that "the effects of lead poisoning can be permanent and disabling."
In response to the concern, Stanley told NBC News that while they do use a lead pellet in the manufacturing process, in order to help insulate drinks from outside temperatures, it is covered by stainless steel and would not be able to contaminate drinks unless the stainless steel barrier was removed, which the Stanley spokesperson told NBC was possible but “rare.”
“Our engineering and supply chain teams are making progress on innovative, alternative materials for use in the sealing process,” the spokesperson said. Stanley also reiterated that it follows all FDA guidelines and requirements during the manufacturing process.
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TIME reached out to Stanley for further information regarding its use of lead and plans for future alternatives.
The concern surrounding the materials used by Stanley comes after limited-edition tumblers caused a frenzy at Target, with crowds of people rushing to buy the Cosmo Pink and Target Red cups, released on Dec. 31, as part of a “Galentine’s Collection.”
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