Texas AG Launches Protein Powder Investigation Over Heavy Metal Contamination Concerns

Texas Attorney General Ken Paxton announced an industry-wide investigation into protein powder manufacturers, citing independent testing that identified elevated concentrations of lead, cadmium, and inorganic arsenic in widely sold products.¹ The probe targets potential violations of the Texas Deceptive Trade Practices Act, specifically whether companies misrepresented the safety of their products or failed to disclose known contamination to consumers.

No specific brands or manufacturers have been named. For finished product manufacturers, the investigation arrives during a period of sustained scrutiny over heavy metal content in plant-based and blended protein supplements, and raises compliance questions that extend beyond Texas.

"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," said Paxton. "Far too many corporations have snuck harmful ingredients in their products, and I am committed to doing everything I can to help Make America Healthy Again."

What Testing Triggered the Texas Attorney General's Investigation Into Protein Powders?

The investigation draws on 2 rounds of independent third-party testing. Consumer Reports tested 23 protein products and found that lead levels in plant-based protein powders were, on average, 9 times higher than those made with dairy proteins such as whey and twice as high as beef-based products.

Three products also exceeded Consumer Reports' level of concern for cadmium and inorganic arsenic. Separately, the Clean Label Project tested 160 protein powder products and reported that 47% exceeded California Proposition 65 limits for toxic heavy metals in a single serving.

The attorney general's office cited the FDA’s position that there is no known safe level of lead exposure, and noted that children, pregnant women, and older adults face the greatest risk from chronic heavy metal exposure. Chronic lead exposure has been associated with immune suppression, reproductive problems, kidney damage, and elevated blood pressure in adults.

Is the Underlying Science Behind These Heavy Metal Findings Disputed?

The industry's response to the testing that prompted the investigation has been pointed and consistent. Back in October 2025, the Natural Products Association (NPA) previously challenged² both Consumer Reports and the Clean Label Project on methodological grounds when similar reports surfaced, and those objections remain central to how the supplement industry is framing its response.

The NPA had argued at the time that modern analytical testing is sensitive enough to detect trace amounts of naturally occurring heavy metals—lead, cadmium, arsenic—that are present broadly in soil, water, and plant-based raw materials, and that detection at parts-per-billion concentrations does not in itself constitute a public health risk. The organization also raised concerns about the Clean Label Project's refusal to disclose its full testing methodology and funding sources, an issue it raised formally and received no response to.

A 2025 peer-reviewed cross-sectional study published in the Journal of Nutritional Science,³ which tested 22 commercially available protein powders using validated analytical methods, found that concentrations of toxic elements including arsenic, cadmium, mercury, and lead were low or undetectable across the samples tested.

The authors nonetheless cautioned that the findings cannot be generalized as a safety guarantee given the supplement industry's reliance on voluntary regulatory compliance, and called for ongoing monitoring, particularly of grey market products.

That context does not resolve the investigation's legal questions, which turn not on whether the detected metals pose a health risk per se, but on whether manufacturers accurately disclosed what was in their products.

Fast forward to present day, the NPA revealed on LinkedIn⁴ that that it has requested a meeting with Paxton, noting that “the third-party testing data cited by your office … does not account for the robust safeguard our members implement throughout their manufacturing process, nor does it reflect the scientific consensus of the federal agencies that Congress has charged with regulating dietary supplements.”

What Are the Regulatory Standards Governing Heavy Metals in Protein Supplements?

There is no single federal heavy metal limit specifically applicable to protein powder dietary supplements. The FDA has established action levels for lead in food products intended for infants and young children under its Closer to Zero initiative, but these do not directly govern adult supplement products.⁵ California Proposition 65 thresholds, which the Clean Label Project used as benchmarks, are among the most stringent in the country and are not equivalent to FDA safety standards, a distinction the industry has repeatedly emphasized. Supplement manufacturers are required under federal Good Manufacturing Practices to test for contaminants and ensure compliance with federal standards, but those standards leave meaningful interpretive latitude on heavy metals.

This regulatory gap is relevant to manufacturers operating across multiple states. A product that complies with federal current Good Manufacturing Practice requirements may nonetheless exceed Proposition 65 thresholds, creating legal exposure in California or, as the current case illustrates, serving as the evidentiary basis for a state-level consumer protection investigation.

References

1. Office of the Attorney General of Texas. Attorney General Ken Paxton launches industry-wide investigation into protein powder manufacturers to protect Texans from heavy metals, including lead and cadmium, found in popular protein powders. June 8, 2026. Accessed June 10, 2026. https://www.texasattorneygeneral.gov/news/releases/attorney-general-ken-paxton-launches-industry-wide-investigation-protein-powder-manufacturers

2. Natural Products Association. NPA slams Consumer Reports' misleading report on protein powder: science, not scare tactics, should guide public health. October 15, 2025. Accessed June 10, 2026. https://www.npanational.org/news/npa-slams-consumer-reports-misleading-report-on-protein-powder-science-not-scare-tactics-should-guide-public-health/

3. Horváth IL, Kajner G, Galbács G, Csupor D. Analysis of heavy metal content in protein powders available on the Hungarian market: a reassuring snapshot, but not a reassuring quality guarantee. J Nutr Sci. 2025;14:e49. doi:10.1017/jns.2025.10024

4. Natural Products Association. LinkedIn post from the NPA containing its request for a meeting with Texas Attorney General Ken Paxton. June 9, 2026. Accessed June 10, 2026. https://www.linkedin.com/feed/update/urn:li:activity:7470192542664400896/

5. US Food and Drug Administration. Closer to Zero: Reducing childhood exposure to contaminants from foods. FDA.gov. Updated January 6, 2025. Accessed June 10, 2026. https://www.fda.gov/food/environmental-contaminants-food/closer-zero-reducing-childhood-exposure-contaminants-foods