Costco Sued Over Protein Powder with Lead and Arsenic

Costco Wholesale Corporation is facing a proposed class-action lawsuit alleging that Orgain Organic Protein Powders sold in its stores contain dangerous levels of toxic heavy metals — including lead, arsenic, and cadmium — without adequate warning to consumers. The lawsuit, filed July 7 in the U.S. District Court for the Western District of Washington, was brought by seven plaintiffs from across the United States who argue that the retailer marketed the products as safe and healthy while allegedly failing to disclose the presence of hazardous contaminants.

Background: A Growing Concern Over Heavy Metals in Protein Powders

The lawsuit is the latest development in a controversy that has been building since early 2025. The Clean Label Project, a nonprofit focused on consumer product safety, published a study in January 2025 testing 160 protein powder products from 70 leading brands. The study found that 47% exceeded California’s Proposition 65 safety thresholds for toxic heavy metals in a single serving, with organic and plant-based products showing higher contamination levels.

Several months later, Consumer Reports published its own investigation in October 2025, testing 23 protein powders and ready-to-drink shakes. The organization found that more than two-thirds of the products contained more lead in a single serving than its food safety experts consider safe to consume in a day. Consumer Reports flagged Orgain’s Vanilla Bean flavor specifically, noting it contained lead at 143% of the organization’s level of concern.

The Lawsuit: What the Plaintiffs Allege

According to the complaint, independent testing commissioned by the plaintiffs found that Orgain’s Vanilla Bean flavor contained lead levels exceeding California’s Proposition 65 limits by more than 600%. The lawsuit alleges violations of the Washington Consumer Protection Act, false advertising, and failure to disclose material risks.

Steve Berman, managing partner of the law firm Hagens Berman representing the plaintiffs, said: “Many consumers who buy and use protein powder do so routinely as part of a continuing focus on their fitness and health. 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 specifically targets two varieties of Orgain Organic Protein Powder — Vanilla Bean and Creamy Chocolate Fudge — which are marketed as providing “good, clean nutrition.” The plaintiffs argue that Costco, as a major national retailer with sophisticated supply-chain management, “knew or should have known” about the presence of heavy metals in the products it sells.

Orgain’s Response

Orgain pushed back on the allegations in a statement provided to USA Today on July 9. “Orgain products are safe to consume,” the company said. “While trace amounts of substances that occur in the environment can be present in plant-based ingredients, our products comply with applicable food safety standards and guidance. We stand behind the safety and quality of our products.”

Costco’s product pages for the Orgain powders include a disclaimer stating that “product details have been supplied by the manufacturer and are hosted by a third party.” However, the plaintiffs argue that Costco controls what appears on its website and in stores, making the retailer responsible for the information presented to consumers.

Regulatory and Industry Response

The issue has drawn attention from state regulators. In June 2026, Texas Attorney General Ken Paxton announced an industry-wide investigation into protein powder manufacturers over concerns about heavy metal contamination. “Protein is a vital macronutrient for human health, and Texans deserve clean protein powders without having to worry whether the products contain heavy metals or other harmful chemicals,” Paxton said.

California lawmakers also introduced a bill in February 2026 requiring mandatory testing and public disclosure of heavy metals in protein products — a direct response to the Clean Label Project and Consumer Reports findings.

Why Plant-Based Protein Powders May Carry Higher Risk

Experts have noted that plant-based protein powders — particularly those derived from peas, rice, and hemp — may absorb heavy metals from soil more readily than animal-based sources. Consumer Reports found that lead levels in plant-based protein powders were on average nine times higher than dairy-based products and twice as high as beef-based alternatives. Organic farming practices, while avoiding synthetic pesticides, do not necessarily prevent heavy metal contamination from soil and water, creating a paradox for health-conscious consumers.

What’s Next

The lawsuit seeks class-action status and asks the court to require Costco to disclose the presence and levels of heavy metals in the products it sells or to stop selling them without adequate warnings. Costco’s stock (COST) fell 4.21% ($40.16) to $912.97 on the day the news broke, though broader market factors may have contributed to the decline.

As the case progresses, it could set a significant precedent for retailer responsibility in supplement safety, potentially forcing major retailers to implement more rigorous testing and disclosure requirements for heavy metals in dietary supplements.