For years, Sen. Ron Johnson has been spreading conspiracy theories and misinformation about COVID-19 and the safety of vaccines.

He’s promoted disproven treatments for COVID-19 and claimed, without evidence, that athletes are “dropping dead on the field” after getting the COVID-19 vaccination. Now the Wisconsin politician is endorsing a book by a discredited doctor promoting an unproven and dangerous treatment for autism and a host of ailments: chlorine dioxide, a chemical used for disinfecting and bleaching. 

The book is “The War on Chlorine Dioxide: The Medicine that Could End Medicine” by Dr. Pierre Kory, a critical care specialist who practiced in Wisconsin hospitals before losing his medical certification for statements advocating using an antiparasite medication to treat COVID-19. The action, he’s said, makes him unemployable, even though he still has a license.

Kory has said there’s a globally coordinated campaign by public health agencies, the drug industry and the media to suppress evidence of the medicinal wonders of chlorine dioxide. His book, according to its website, contends that the “remarkable molecule” works “to treat everything from cancer and malaria to autism and COVID.”

The book jacket features a prominent blurb from Johnson calling the doctor’s treatise: “A gripping tale of corruption and courage that will open eyes and prompt serious questions.” 

Chlorine dioxide is a chemical compound that has a range of applications, including as a disinfectant and deodorizer. Food processing plants apply it to sanitize surfaces and equipment. Hospitals use it to sterilize medical devices, and some municipalities use low levels to treat public water supplies. Paper mills rely on it to whiten wood pulp. Safety experts advise those who handle it to work in well-ventilated spaces and to wear protective gloves.

Concentrations in drinking water systems higher than 0.8 milligrams per liter can be harmful, especially to infants, young children and fetuses, according to the Environmental Protection Agency. 

Still, for many years people in online discussion groups have been promoting the use of chlorine dioxide in a mixture that they call a “miracle mineral solution,” ingested to rid people of a host of maladies. The Food and Drug Administration has warned that drinking these chlorine dioxide mixtures can cause injury and even death. 

It is not medicinal, despite Kory’s contention. “It is all lunacy. Absolutely, it’s 100% nonsense,” said Joe Schwarcz, director of McGill University’s Office for Science and Society in Montreal and an expert on the threat of pseudoscience. Schwarcz has written articles about the so-called miracle mineral solution, calling it “a poison” when it’s in high concentrations. 

Kory’s book, set to be released to the public in January, argues that word of chlorine dioxide’s effectiveness has been suppressed by government and medical forces that need people to remain perpetually ill to generate large profits. The use of the word “war” in the title is fitting, Kory said in a recent online video on his co-author’s Substack. “In the book I detail many, many assassination attempts of doctors who try to bring out knowledge around chlorine dioxide,” he said.

Johnson confirmed to ProPublica in an email that he authorized the statement on the cover. “After reading the entire book, yes I provided and approved that blurb,” he said. “Have you read the book?”

ProPublica asked Kory and his co-author, Jenna McCarthy, to provide an advance copy, an interview and responses to written questions. Kory did not respond. McCarthy wrote in an email to ProPublica that she was addressing some of the questions on her Substack. (She did not send a book or agree to an interview.)

The book “is a comprehensive examination of the existing evidence and a plea for open-minded inquiry and rigorous research,” she wrote on Substack. She dismissed warnings about chlorine dioxide’s toxicity in high concentrations, writing: “Everything has a toxic dose — including nutmeg, spinach, and tap water.” 

She said that chlorine dioxide is being studied in controlled settings by researchers in the United States and Latin America and that “the real debate is how it should be used, at what dose, and in which clinical contexts.”

Her Substack post was signed “Jenna (& Pierre).”

Johnson did not agree to an interview and did not answer questions emailed to his office by ProPublica, including whether he views chlorine dioxide as a world-changing medical treatment and whether he believes the FDA warnings are false. 

“It’s Called Snake Oil”

Johnson has been an advocate of Kory’s for years, calling the doctor as an expert witness in two 2020 Senate hearings. In one, Kory championed taking the drug ivermectin, an antiparasite medicine, to treat COVID-19. 

In 2021, an analysis of data from clinical trials concluded that ivermectin could reduce deaths from COVID-19 and may produce other positive effects. McCarthy cited that analysis in her Substack response.

In 2022, however, the American Journal of Therapeutics, which had published the study, warned that suspicious data “appears to invalidate the findings” regarding ivermectin’s potential to decrease deaths. 

Later clinical trials have found no beneficial effect of ivermectin for COVID-19, and the FDA has warned that taking large doses can be dangerous. The drug’s manufacturer has said it hadn’t found any scientific basis for the idea that ivermectin can effectively treat COVID-19. Kory, though, continued advocating for ivermectin.

In 2024 the American Board of Internal Medicine, which credentials physicians in certain specialties, revoked Kory’s certifications in internal medicine, pulmonary disease and critical care for making false and misleading public statements about the ability of ivermectin to treat COVID-19. Hospitals and many insurance networks typically require doctors to be board certified.

Kory vigorously fought the disciplinary action, arguing to the ABIM that he provided substantial medical and scientific evidence to support his recommendations for addressing COVID-19, though not the “consensus-driven” approach. He also sued the board in federal court, citing his free speech rights in a case that is still progressing in the 5th U.S. Circuit Court of Appeals. On Substack, McCarthy excoriated the ABIM, saying it “bullies physicians” and “enforces ideological conformity.”

In 2022, Johnson and Kory penned a Fox News op-ed opposing a California bill that would strip doctors’ licenses for espousing misinformation about COVID-19. The bill became law but was repealed after a court fight. A federal judge found the statute’s definition of misinformation to be too vague, which could infringe on doctors’ right to free speech.

Johnson, who has been in Congress since 2011, has a history of advocating for experimental treatments and viewing the government as an impediment. Dr. Peter Lurie, president and executive director of the Center for Science in the Public Interest, a public health advocacy group, said that among members of Congress, Johnson was “an early adopter of anti-science ideas.” 

Lurie said that Johnson is no longer an outlier in Washington, which now has many more elected lawmakers whom he considers anti-science. “What may have started off as the cutting edge of an anti-science movement has now turned into a much more broader-based movement that is supported by millions of people,” he said.

Earlier this year, Johnson held a hearing highlighting a flawed study claiming that vaccinated children had an increased rate of serious chronic diseases when compared to children who were not vaccinated. The conclusion questions the scientific consensus that vaccines are safe. The study’s researchers chose not to publish it because of problems they found in their data and methodology.

In November, Johnson and Kory were listed among the speakers at a conference of the Children’s Health Defense, a nonprofit that stirs anti-vaccine sentiment. It was launched in 2018 by Health and Human Services Secretary Robert F. Kennedy Jr., whose FDA is considering new ways to more closely scrutinize vaccine safety. 

HHS did not respond to requests from ProPublica about Kennedy’s views on chlorine dioxide. At his confirmation hearing, Kennedy praised President Donald Trump for his wide search for a COVID-19 remedy in his first term, which Kennedy said included vaccines, various drugs, “even chlorine dioxide.”

Kory’s publisher is listed as Bella Luna Press, which has issued at least two other titles by McCarthy. “Thanks to the Censorship Industrial Complex, you won’t find The War on Chlorine Dioxide on Amazon or at Barnes & Noble. We had to design and build this website, figure out formatting and printing and shipping, and manage every aspect of order processing ourselves,” the book’s website states. (A representative for Bella Luna could not be reached for comment.)

As this new book is released, the autism community is also grappling with another controversy: the unsubstantiated assertion by Kennedy that Tylenol use by pregnant women poses an increased risk of autism. In addition, under Kennedy, the Centers for Disease Control and Prevention revised its website in November to cast doubt on the long-held scientific conclusion that childhood vaccines do not cause autism.

Some parents of children with autism, desperate for a remedy, have long reached for dubious and at times dangerous panaceas, including hyperbaric oxygen chambers and chelation therapy, used for the treatment of heavy metal poisoning. Neither method has been proven effective.

Helen Tager-Flusberg, director of the Center for Autism Research Excellence at Boston University, said Johnson has “acted extremely irresponsibly” in lending his name to a book making claims about chlorine dioxide treating autism.

“Wisconsin is filled with experts — clinical experts, medical experts, scientists — who understand and have studied autism and treatments for autism for many many years,” she said. “He’s chosen to completely ignore the clinical and the scientific community.”

People with autism may take medication to reduce anxiety, address attention problems, or reduce severe irritability. Many benefit from behavioral interventions and special education services to help with learning and functional abilities. But there is no cure, said Tager-Flusberg.

Referring to chlorine dioxide, she said: “We have had examples of this probably throughout the history of medicine. There’s a word for this, it’s called snake oil.”

In her response on Substack to ProPublica, McCarthy wrote that “chlorine dioxide is being used to treat (nobody said ‘cure’) autism with life-changing results.”

The Search for Miracle Cures

The mother of an autistic son, Melissa Eaton of North Carolina, heard Kory reference his book in early November on The HighWire, an internet talk show hosted by Del Bigtree, a prominent vaccine skeptic and former communications director for Kennedy’s 2024 presidential campaign. She then looked up the book online and noticed Johnson’s endorsement.

Eaton for many years has worked to expose people who peddle chlorine dioxide and to report apparent injuries to authorities. She monitors social media forums where parents discuss giving it to their children orally or via enemas. Sometimes the families reveal that their children are sick. “They’re throwing up and vomiting and having diarrhea and rashes,” Eaton said.

Some adherents advise parents that the disturbing effects indicate that the treatment is working, ridding the body of impurities, or that the parents should alter the dosage. 

“Most of these kids are nonverbal,” Eaton said. “They’re not able to say what’s hurting them or what’s happening to them. The parents feel they’re doing the right thing. That’s how they view this: They’re helping to cure autism.”

The idea that chlorine dioxide can be a miracle cure began to spread about 20 years ago when a gold prospector, Jim Humble, wrote a book claiming his team in Guyana fell ill with malaria and recovered after drinking safe amounts of chlorine dioxide. 

Humble later co-founded a “health and healing” church in Florida with a man named Mark Grenon, who called himself an archbishop and sold a chlorine dioxide solution as a cure for COVID-19. They described it as a “miracle mineral solution,” or MMS.

Grenon went to prison in 2023 for conspiring to defraud the United States by distributing an unapproved and misbranded drug. The scheme took in more than $1 million, according to prosecutors.

An affidavit in the case filed by a special agent with the FDA Office of Criminal Investigations noted: “FDA has received numerous reports of adverse reactions to MMS. These adverse reactions include hospitalizations, life-threatening conditions, and death.”

Grenon, who is now out of prison, told ProPublica that he too is writing a book about chlorine dioxide. “My book will tell the truth.” He declined further comment. 

Chlorine dioxide is currently used in many ways that are not harmful. It is found in some consumer products like mouthwashes, but it is not meant to be swallowed in those instances. (One popular mouthwash warns to “keep out of reach of children.”) It’s also available to consumers in do-it-yourself packages where they combine drops from two bottles of different compounds — commonly sodium chlorite and hydrochloric acid — and add it to water. Hikers often carry the drops, or tablets, using small amounts to make quarts of fresh water potable.

But numerous online shoppers post product reviews that go further, referring to it as a tonic. Various online guides, some aimed at parents of autistic children, recommend a shot-glass-size dose, sometimes given multiple times a day and even hourly. That can far exceed the threshold the EPA considers safe.

McCarthy, addressing ProPublica on Substack, wrote: “You point to various online guides that offer what could be considered dangerous dosing instructions. We agree, the internet is a terrifying wasteland of misinformation and disinformation.”

In the Substack video, Kory said he felt compelled to spread the word about chlorine dioxide much as he did about ivermectin, even though it cost him professionally. 

He no longer has a valid medical license in Wisconsin or California, where he did not renew them, according to the Substack post. His medical licenses in New York and Michigan are active.

“I like to say I was excommunicated from the church of the medical establishment,” he said in the Substack video. As a result, he said, he turned to telehealth and started a practice. 

In the Nov. 6 HighWire episode hosted by Bigtree, the discussion included talk not just of chlorine dioxide’s medicinal potential but also of how cheap and easy it is to obtain. 

“On Amazon, it’s literally, you get two bottles, well, it comes in two,” Kory started to explain, before stopping that train of thought. 

“I wouldn’t know how to make it,” he said.