California is the first state in the nation to require testing and public disclosure of toxic heavy metals in prenatal vitamins. Governor Newsom signed Senate Bill 646 into law on October 11, 2025, establishing a framework that mirrors the testing and transparency requirements California already set for baby food under Assembly Bill 899.
Classified as dietary supplements, prenatal vitamins have largely evaded regulatory oversight. The U.S. Food and Drug Administration (FDA) does not require pre-market approval or final product testing for dietary supplements, which means consumers had no way to know what contaminants might be in the products they take during one of the most vulnerable periods of their lives.
But the new law changes things.
Beginning January 1, 2027, manufacturers of prenatal vitamins sold in California must test a representative sample of each lot of their finished product for arsenic, cadmium, lead, and mercury—and publicly disclose the results, including the name and level of each heavy metal detected.
SB 646 was prompted by research that found widespread heavy metal contamination in commercially available prenatal supplements. A peer-reviewed study published in Environmental Research by researchers at the University of Miami, Clean Label Project, and Ellipse Analytics analyzed 156 over-the-counter prenatal vitamins and nine prescription prenatal supplements. The results were alarming: 83% of commercially available samples had quantifiable levels of lead, and 73% contained quantifiable cadmium. Fifteen percent of the products exceeded California’s Proposition 65 safety threshold of 0.5 micrograms of lead per serving. Prescription prenatal vitamins were not exempt—one-third of those tested also exceeded the Prop 65 threshold for lead.
These findings echoed a 2023 Government Accountability Office report that found lead in half of the prenatal vitamins sampled and cadmium in several others. Advocacy organizations, including the Environmental Working Group and Unleaded Kids, pushed for legislative action in response to the mounting evidence. Senator Dr. Akilah Weber Pierson, a board-certified OB-GYN, introduced SB 646 in February 2025.
SB 646 was introduced against a backdrop of growing legislative concern over heavy metal exposure during pregnancy and early childhood. In 2021, a Congressional investigation found significant heavy metal contamination in baby food products from major manufacturers. The Subcommittee on Economic and Consumer Policy concluded that the presence of arsenic, lead, cadmium, and mercury in those products posed risks to infant neurological development. That investigation led California to pass AB 899 in 2023, requiring baby food manufacturers to test and disclose heavy metal levels.
Senator Weber Pierson, in introducing SB 646, cited research indicating that heavy metals can cross the placental barrier during pregnancy. The bill’s legislative findings reference studies linking prenatal and early childhood heavy metal exposure to adverse developmental outcomes.
A 2023 meta-analysis published in Frontiers in Pediatrics, which reviewed 53 studies involving over 5,000 children, was among the research cited by advocacy groups supporting the legislation. Co-sponsors of the bill included the Environmental Working Group, the American College of Obstetricians and Gynecologists, and Unleaded Kids.
The legislature’s rationale was straightforward: if California requires transparency about what’s in baby food, the same standard should apply to the supplements taken during pregnancy.
The law applies to any bulk or packaged prenatal vitamin sold, manufactured, delivered, or offered for sale in California. Starting January 1, 2027, manufacturers must test a representative sample of each lot of their finished product at a proficient, ISO-accredited laboratory for arsenic, cadmium, lead, and mercury.
Test results must be posted on the manufacturer’s website and made available to the public without requiring a UPC number, lot number, or proof of purchase. Product packaging must include a QR code linking consumers directly to the testing results, along with a statement directing them to the information. The law also requires manufacturers to provide test results to any authorized agent of the California Department of Public Health upon request.
Prenatal vitamins that fail to meet the requirements are prohibited from sale in California, and violations are punishable as a misdemeanor under the Sherman Food, Drug, and Cosmetic Law.
California has a track record of setting standards that ripple outward. Consumer advocates hope that AB 899’s disclosure requirements for baby food will reshape manufacturer behavior, and preliminary data from Unleaded Kids suggests that some companies have reduced heavy metal levels in their baby food products.
SB 646 could potentially drive positive changes in the prenatal supplement industry. Because California is such a large consumer market, manufacturers who adjust their testing and formulation practices to comply with the law are likely to apply those standards nationally rather than maintain separate product lines. The legislation may also set a precedent for extending testing and disclosure requirements to related product categories.
Wisner Baum is pursuing claims on behalf of thousands of families alleging their children were harmed by heavy metals in baby food. The cases are for children diagnosed with autism and ADHD, disorders that research has linked to heavy metal exposure.
If your child suffered developmental delays or neurological harm that may be connected to heavy metals in baby food, you may be eligible for a legal case. Contact Wisner Baum today to schedule a free, confidential consultation.
SB 646 covers bulk and packaged prenatal multivitamins sold, manufactured, delivered, or offered for sale in California. This includes national brands that sell into the state.
The testing and disclosure requirements take effect January 1, 2027. Products shipped to retailers or consumers on or after that date must comply with the labeling requirements, including the QR code linking to test results.
Prenatal vitamins are classified as dietary supplements under federal law. Unlike pharmaceuticals, the FDA does not require pre-market approval, pre-market testing, or final product testing for dietary supplements. There is currently no federal requirement to test prenatal vitamins for heavy metals or to disclose results to consumers.
The Environmental Research study found that the vast majority of prenatal vitamins tested contained quantifiable levels of lead and cadmium. According to the study’s authors, heavy metals can cross the placental barrier, and the researchers called for enforceable regulations to address contamination in prenatal supplements. The California legislature cited these concerns in passing SB 646.
Prenatal vitamins that do not meet SB 646’s testing and disclosure requirements are prohibited from sale in California. Violations are punishable as a misdemeanor under the Sherman Food, Drug, and Cosmetic Law.
