HHS Urges States to End Medicaid Coverage for Mercury Amalgam Fillings; 43 Countries Already Ban Them

HHS and the Centers for Medicare and Medicaid Services (CMS) announced an effort to encourage states Medicaid directors to phase out coverage of mercury-containing dental amalgam fillings out of concern for detrimental health effects, especially for pregnant women and their babies, women trying to become pregnant, children under the age of six, people with neurological diseases or impaired kidney function, and individuals with mercury allergies or sensitivities.

Dental amalgam is approximately 50% mercury by weight and is mixed with other metals such as silver, tin, and copper. The material poses health and environmental risks, and mercury-free alternatives are widely available.

“Mercury has no place in the mouths of our children or in modern American health care,” said HHS Secretary Robert F. Kennedy Jr. “For decades, we have relied on a material that contains one of the world’s most toxic heavy metals when safe, effective mercury-free alternatives are widely available. The Make America Healthy Again agenda means confronting outdated practices that needlessly expose Americans to toxic substances. Taxpayer dollars should support the safest care available—not yesterday’s materials. It’s time to turn the page on dental amalgam and help every state move toward safer, mercury-free care.”

A 2020 research paper published in the journal Neurotoxicology said mercury is a “highly potent cell toxin” and that mercury vapor released from dental amalgams “is the predominant source of mercury in the human adult and fetal central nervous systems in populations of developed countries.” Researcher Berlin Maths explained that only small populations that consume large amounts of methylmercury-containing fish can exceed the mercury exposure from dental amalgam fillings.

The FDA and EPA issued guidelines in 2004 that recommend people eat no more than 12 oz of shrimp, canned light tuna, salmon, pollock, and/or catfish. That equates to approximately two serving sizes per week. The average person has 14 dental amalgam surfaces and would have the same amount of mercury exposure as approximately 3.5 servings per week, according to an analysis by Mark Richardson. The risk analysis compared elemental vapor exposure from dental amalgams to methyl-mercury exposure from fish.

The World Health Organization (WHO) lists mercury as one of the top ten chemicals of major public health concern. According to the WHO, it can affect the nervous, digestive, immune, and respiratory systems, as well as the kidneys, skin, and eyes.

Sweden began phasing out mercury dental amalgams in the 1990s to early 2000s, while Norway enacted a full prohibition around 2008-2011. As of 2025, at least 43 countries have imposed legal bans on the use of mercury-containing dental amalgam; some have limited medical-necessity exceptions. Other nations have effectively eliminated it through public-program withdrawals, import/manufacturing bans, or declarations of non-use. Well over 60 countries have substantially restricted the use of mercury dental amalgams.

The use of mercury dental amalgams has declined substantially in the US due to the listed health concerns. Dental amalgams accounted for 8% of all dental restorative procedures in the US in 2022, according to data from the Transformed Medicaid Statistical Information System. An American Dental Association study of data from 2015 and 2016 found 51.5% of all restored teeth in the US contained amalgam. Dentists have been slowly moving away from amalgam fillings since the turn of the century, but that accelerated after 2013 when the US joined the Minamata Convention on Mercury. That is an agreement to limit mercury emissions, including a phasedown of dental amalgam.

Still, the latest effort by Secretary Kennedy and CMS Administrator Dr. Oz will not require states to change their Medicaid policies to prevent reimbursement for mercury-based dental amalgams. The American Dental Association supports the phasing out of the dental amalgams, but calls upon the states to give dentists the option to “retain the ability to select the most appropriate evidence-based treatment for each individual patient.”

The ADA says it supports a phase-down process of mercury for environmental reasons, but believes it can be the best treatment option under some circumstances. The ADA also points to the 2025 Minamata Convention on Mercury, which states that the manufacture, import, and export of dental amalgam should be phased out globally by 2034, except “when its use is considered necessary by the dental practitioner based on the needs of the patient.”

The ADA made a similar statement in February, following the Indian Health Service’s announcement that dental amalgams will be phased out by 2027. The ADA also stated that “no properly designed scientific study has demonstrated that dental amalgam causes any long-term health effects or disease. The removal of clinically serviceable amalgam restorations solely to substitute a material that does not contain mercury is unwarranted and violates the ADA Principles of Ethics and Code of Professional Conduct.”

The ADA has also continued to support water fluoridation despite a landmark court decision finding that recommended water fluoridation levels pose an “unreasonable risk to human health.” The HighWire has reported on partnership programs with pharmaceutical companies that grant a “seal of approval” to dental products. Many of these dental hygiene products with a seal of approval include fluoride as a main ingredient.

Dr. Oz and Secretary Kennedy disagree with the ADA’s position that mercury fillings should remain available under certain circumstances, and they are encouraging state Medicaid directors to take action.

“Americans should feel confident that the health care they receive is always working in their best interest,” CMS Administrator Dr. Oz said. “That’s why we’re urging state Medicaid programs to end the use of mercury-containing dental fillings. This is a straightforward and meaningful step that reflects our shared commitment to safe, higher quality care for all Americans and supports the Trump Administration’s broader goal to Make America Healthy Again.”