Costco sued over protein powder, plaintiffs allege no warning about presence of toxic heavy metals

The plaintiffs allege they purchased the product believing it was a healthy, high-quality supplement based on its labeling and marketing.

WASHINGTON — Wholesale retailer Costco is facing a proposed class-action lawsuit alleging the retailer misled consumers by selling protein powder without disclosing potentially harmful levels of toxic heavy metals. 

Costco Wholesale Corp. is being sued over sales of Orgain Organic Protein Powder,  in a lawsuit filed Tuesday in federal court in Washington. 

The suit, which names several plaintiffs, claims Costco violated consumer protection and false advertising laws by failing to warn customers that the protein powder contains lead, cadmium and arsenic.

Seven of the plaintiffs allege they purchased the product believing it was a healthy, high-quality supplement based on its labeling and marketing. 

“Though represented to have ‘quality ingredients and higher standards,’ and to provide ‘good clean fuel,’ and that Orgain is ‘relentless about quality,’ the contaminated products’ representation is not true and is misleading,” the lawsuit alleges, “as the contaminated products are tainted with heavy metals which include lead, cadmium, and arsenic.”

According to the 87-page complaint, consumers could not reasonably determine whether the protein powder contained heavy metals because doing so requires specialized laboratory testing.

“Reasonable consumers … could not learn of the inclusion of heavy metals in the contaminated products unless Costco included a proper disclosure because identifying the presence of heavy metals requires expensive and sophisticated laboratory testing,” the lawsuit reads. “But Costco failed to perform or require any heavy metal testing, or to disclose the presence of heavy metals.”

The lawsuit cites testing conducted by Consumer Reports in October 2025, which found that Orgain’s Vanilla Bean Organic Protein Powder exceeded the publication’s “level of concern” for lead, measuring at 143% of that threshold. Consumer Reports categorized the product as one that is “okay to eat occasionally.”

The plaintiffs argue that Costco’s marketing created the impression the product was free from harmful contaminants. In addition to displaying the USDA Organic seal, the product’s online listing describes the protein powder as “relentless about quality” and references the manufacturer’s mission to help people live healthier lives through “good, clean nutrition.”

The lawsuit contends those statements are deceptive because foods containing elevated levels of toxic heavy metals “are neither nutritious nor healthy.”

“Many consumers who buy and use protein powder do so routinely as part of a continuing focus on their fitness and health,” Steve Berman, managing partner and co-founder of Hagens Berman, which represents the plaintiffs, said in a statement. “These same health-conscious consumers have unknowingly ingested alarming levels of toxic heavy metals — lead, cadmium and arsenic — again and again, trusting that Costco’s quality assurance would not allow something like this to happen.”

The lawsuit also points to what the plaintiffs describe as a regulatory gap. Unlike prescription drugs, protein powder supplements are not reviewed, approved or routinely tested by the Food and Drug Administration before they are sold, making consumers more reliant on manufacturers’ and retailers’ representations about product quality and safety.

The plaintiffs allege Costco concealed information about the alleged presence of heavy metals and argue they either would not have purchased the protein powder or would have paid less for it had they known about the contaminants.

“Consumers nationwide trust Costco,” Berman said. “Based on our investigation and product testing, we believe Costco knew or should have known that its Orgain protein powder failed to live up to its promises of safety and quality.”

The proposed class-action seeks to represent consumers in Washington, California, Illinois, Minnesota, Ohio and Texas. The plaintiffs are asking the court to require Costco to disclose the presence and levels of heavy metals in the protein powder and to stop selling the product until those disclosures are made.

The plaintiffs are asking for a jury trial in the case. 

Costco has not publicly responded to the lawsuit. A request for comment was sent to Costco, and this story will be updated if and when Costco responds.