California State Senator Steve Padilla introduced a bill to the state senate, which would require protein powder manufacturers to publicly disclose heavy metal testing results for their products. The bill, SB 1033, is co-sponsored by Consumer Reports and the Environmental Working Group.

“The rapidly expanding protein industry is putting untested and, in some cases, unsafe products onto store shelves,” said Padilla. “We need to put common sense guardrails in place to hold manufacturers accountable, require proper testing, and ensure families can trust that the products they buy won’t put their health at risk.”

The FDA requires that manufacturers ensure dietary supplements are not contaminated with heavy metals, under current Good Manufacturing Practices (cGMP) requirements, though it doesn’t set specific numerical limits

Another California law, enacted last year, requires that manufacturers of dietary supplements and baby foods intended for children under the age of 2 test for heavy metals and publicly disclose the results. Similarly, a California state law, SB 646, will require prenatal manufacturers to publicly disclose heavy metal testing results starting on Jan 1, 2027.

Consumer Reports’ Study

In October 2025, Consumer Reports tested 23 popular protein powders, and found that two-thirds of tested products contained levels of lead that were above what the organization reports is safe to consume in a day, above the threshold of 0.5 micrograms.

The organization noted that plant-based products, on average, had nine times the amount of lead found in dairy proteins, and twice as much as that found in beef-based proteins.

Trade associations representing the supplements industry noted that Consumer Reports’ threshold in determining whether a product was acceptable, based on California’s Prop 65, is substantially more protective than standards used by other regulatory agencies. They also noted that the lead concentrations in the protein products were comparable to certain foods.

“Our tests have found that toxic heavy metal contamination in protein powders is widespread and has gotten worse since we first analyzed these products 15 years ago,” said Brian Ronholm, director of food policy at Consumer Reports. “No one should have to worry that their protein shake could expose them to dangerous levels of lead and other heavy metal contaminants. This bill will help Californians make healthier buying decisions and create a strong incentive for protein powder manufacturers to get lead and other dangerous heavy metals out of their products.”

“Once companies are required to show their data, contamination drops; it’s that simple,” said Bernadette Del Chiaro, senior vice president for California at Environmental Working Group, pointing to similar public disclosure requirements for baby foods and prenatals. “This bill forces the industry to clean up its act and gives Californians the power to see exactly what they’re being asked to swallow.”

Consumer Reports noted that no amount of lead exposure is considered safe, but the greatest danger comes from repeated or continuous exposure, which is associated with blood pressure issues, immune suppression, reproductive problems, and kidney damage.

In January, Consumer Reports published another round of testing on chocolate protein powders, requested by its members. All tests came back safe for daily or near-daily consumption by the nonprofit’s standards, with lower levels of lead and arsenic than what was found in previous testing, “demonstrating that safer manufacturing is possible,” Consumer Reports said.