Environmental health in Montana
Local exposures worth knowing about
Where you live shapes what you’re exposed to. These are well-documented environmental health issues in Montana, from official public-health sources, with context from integrative medicine societies on Lyme disease.
The former aluminum smelter in Columbia Falls
The Columbia Falls Aluminum Company plant on the Flathead River made aluminum from 1955 to 2009. Its waste, called spent potliner, was stored in unlined landfills, and arsenic, cyanide and fluoride leached from it into the groundwater. Other parts of the site were contaminated with PAHs from the smelting process. It is a federal Superfund site, and EPA and Montana DEQ are overseeing the cleanup under a 2026 agreement.
Source: US EPA: Columbia Falls Aluminum Company agrees to $57 million cleanup of former smelter site
Asbestos in Libby vermiculite
A mine near Libby supplied over 70 percent of all vermiculite sold in the United States from 1919 to 1990, and that vermiculite was contaminated with asbestos. It was used in most US vermiculite attic and wall insulation. If your home, cabin or outbuilding has vermiculite insulation, EPA advises assuming it contains asbestos and not disturbing it.
Source: US EPA: Protect your family from asbestos-contaminated vermiculite insulation
Smelting legacy in Anaconda
More than a century of milling and smelting near Anaconda produced high concentrations of arsenic, lead, copper, cadmium and zinc, which contaminated soil, groundwater and surface water. EPA placed the Anaconda Co. Smelter site on the Superfund National Priorities List in 1983, and cleanup continues under an $83 million agreement.
Source: US EPA: Landmark agreement entered for the Anaconda Smelter Superfund site
Ticks and Lyme disease
Ticks live across Montana, at every elevation. They’re most active from April through July, with the most encounters in May, though they can be active whenever it’s above freezing. Ticks here can carry Rocky Mountain spotted fever, Colorado tick fever and tularemia. Lyme disease is the most common tickborne illness among Montana residents, but the state reports that those cases were picked up out of state. In 2024, blacklegged (deer) ticks, which can carry Lyme, were found in Montana for the first time, in two eastern counties; the ones tested carried no disease. Check yourself, your kids and your pets for ticks after time outdoors. Integrative medicine groups add context. ILADS (the International Lyme and Associated Diseases Society) notes that fewer than 30% of US patients with Lyme remember a tick bite and fewer than 20% of Lyme rashes look like a classic bull’s-eye, that the standard two-step blood test misses a significant number of infections, and that diagnosis must be made on a clinical basis. One tick bite can pass on more than one infection, and ILADS advises considering co-infections such as Babesia, Anaplasma and Ehrlichia, and Bartonella (whose spread by ticks is still debated), especially when symptoms persist after treatment. ISEAI (the International Society for Environmentally Acquired Illness) counts persistent Lyme, Bartonella and Babesia among environmentally acquired illnesses and notes that people with chronic Lyme are likely to become more sensitive to mold in water-damaged buildings.
Sources: Montana DPHHS: Tickborne illnesses; Montana DPHHS Health Alert Network: Blacklegged ticks identified in Montana (May 2025); ILADS: Lyme disease basics for providers; ISEAI: About environmentally acquired illness
West Nile virus
West Nile virus is the only mosquito-borne illness considered established in Montana. It was first found here in 2002, larger outbreaks come every few years (most recently in 2023), and it was detected again in the 2026 season. About 4 in 5 infected people have no symptoms. About 1 in 5 get a fever, rash, aches and headache, and many have long-lasting fatigue afterward. About 1 in 150 develop a serious illness affecting the brain and nerves. Preventing mosquito bites in summer is the best protection.
Source: Montana DPHHS: West Nile virus
Radon
Radon is a natural radioactive gas from rock and soil. It’s found in every state, and Montana’s geology means many homes test above the EPA’s action level. It causes no immediate symptoms, but long-term exposure is a leading cause of lung cancer, so testing is the only way to know. Inexpensive test kits are widely available.
Source: Montana DEQ: Radon
Arsenic and metals in well water
Many Montanans rely on private wells, which the state does not regulate. Arsenic and manganese occur naturally in some Montana groundwater, and MSU Extension reports finding them above health thresholds in about 10 percent of the wells tested through its program. Testing your well, including for metals, is the owner’s responsibility.
Source: MSU Extension: Testing private well water quality
Living near a former mining, smelting or Superfund site, in a home with water damage or old vermiculite insulation, or with a history of tick bites, Lyme disease or co-infections such as Babesia or Bartonella doesn’t mean you’ll get sick. But these exposures can add to your body’s overall toxic and inflammatory burden, and they may be part of the picture behind chronic fatigue, brain fog, aches, headaches and new sensitivities that routine labs often miss. If you live in Montana and these symptoms sound familiar, your symptoms are real, and Dr. Madeira can help you look at your full exposure history and build a step-by-step, integrative plan with you.
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