Laurel Austin documented her son Jeremy’s first dosing of chlorine dioxide on YouTube. In the 30-second video, broadcast to 4,465 subscribers, Jeremy, 27, sits at a kitchen table as his mother narrates his mood. Then his arms seem to involuntarily twist around one another and he screams into his forearm before taking a bite of a banana.

“Here’s to hoping and praying,” she says.

Austin, 51, is a photographer in Lenexa, Kansas, and a mother of six, four of whom are adults with autism. According to her Facebook posts, she has tried almost every fad online “cure” for autism — a developmental disorder that has no known cure — including treatments for heavy metal poisoning, hormone therapies used in chemical castration and “natural” remedies such as cilantro and algae.

For the last year, according to her social media posts and documents from a police investigation, Laurel Austin has been giving two of her adult sons, Jeremy and Joshua, chlorine dioxide. The Food and Drug Administration warns the solution amounts to industrial bleach, and doctors say it can cause irreparable harm when ingested, including damage to the digestive system and kidneys.

Joshua, 28, is talkative and likes “The Simpsons” and playing retro Nintendo games, while Jeremy, 27, doesn’t speak and can go into rages during which he bites his arms, according to their father, Bradley Austin, who provided police investigation files to NBC News. Joshua and Jeremy live with Laurel Austin, who is their court-appointed guardian, charged with making medical and other decisions for them. Jeremy was living in a group home until his mother took him out to try chlorine dioxide, according to his father.

Since January, when Bradley Austin learned that his ex-wife was using chlorine dioxide on their sons, he’s been trying to stop her. (He’s also exploring fighting for guardianship of his sons.) But the local police, the state’s division of adult protective services and a medical doctor treating Jeremy have all declined to intervene. A police spokesman said there wasn’t enough evidence that chlorine dioxide was dangerous; a caseworker with the Kansas Adult Protective Services told police that she didn’t see the situation as serious enough for the state to take action.

The Austins’ case illustrates the ways in which online health misinformation can become so pervasive that it begins to sway not only those on the fringe who are seeking alternate treatments and explanations but also authorities, including doctors and the police, who are charged with protecting the most vulnerable.

“Health misinformation has started to infiltrate more mainstream,” said Dr. Brittany Seymour, an assistant professor at Harvard University’s School of Dental Medicine, who studies health misinformation online. “Historically we relied on the authority of paywalled scientific papers and there were naturally limiting factors that kept the spread of misinformation at bay, like geography and communication barriers. With the internet and social media, those barriers have been removed.”

Those roadblocks used to keep misinformation from scaling to a dangerous level, Seymour said.

“The voices sharing and spreading misinformation are still small, but we know it really just takes a few now and it can spread far. So the number may be small, but the impact is not.”

The Kansas authorities’ lack of responsiveness has baffled Bradley Austin, who feels he’s run out of options for protecting his sons from their mother’s “treatments.”

“I just want her to stop,” he told NBC News.

It is unclear whether there has been any harm caused to the sons by the bleach. Bradley Austin told police that Joshua’s blood tests in January came back with no abnormalities. In a video posted to YouTube, Laurel Austin said Jeremy refused to be tested.

Laurel Austin declined to be interviewed but said in response to emailed questions that NBC News was “being used as a shameful tool with incorrect information by an absentee father as means to lower or even eliminate his child support obligation to his autistic special needs sons.”

Bradley Austin denied this characterization. The Austins had a court date last year to renegotiate child support, but Bradley Austin said it was unrelated to his concerns about his ex-wife’s use of chlorine dioxide.

When asked additional questions, Laurel Austin replied, “I have nothing further to add.”

Misinformation goes mainstream

The chlorine dioxide Laurel Austin gives to her sons is made by mixing a sodium chlorite solution with an acid activator — both of which are available online for about $20. The solution was first promoted almost two decades ago by a former Scientologist, Jim Humble, as the “Miracle Mineral Solution,” or MMS for short, and sold as a cure for AIDS, cancer and almost every other disease known to humanity.

Doctors say chlorine dioxide’s only effects are harmful, warning that it can damage tissues in the digestive system, disrupt the functioning of red blood cells and lead to kidney failure.

Kerri Rivera, a former Chicago real estate agent who is not a doctor, latched onto the so-called cure and began suggesting it to parents of autistic children around 2012, writing a book and appearing at seminars and on popular conspiracy theorists’ YouTube channels at a time when autism diagnoses were skyrocketing. Rivera declined to comment.

Kerri Rivera is interviewed by NBC Chicago via Skype at her home in Puerto Vallarta, Mexico, in 2015. NBC Chicago

Even as the FDA issued warnings about chlorine dioxide — saying it can cause “severe nausea, vomiting and life-threatening low blood pressure from dehydration” — and the Justice Department prosecuted several sellers who marketed the chemical as a miracle cure, proponents including Rivera built a following online.

Rivera claims to have sold tens of thousands of copies of her book outlining the chlorine dioxide protocol before Amazon banned the title in April. Facebook and YouTube followed suit, deleting accounts and videos promoting chlorine dioxide with thousands of subscribers and millions of views after facing pressure from lawmakers and public health advocates to take responsibility for the spread of health misinformation on their platforms.

Such containment, experts say, is effective when dealing with anti-vaccine and false-cure misinformation, and it’s especially important during health crises, such as the current national resurgence of measles. But true believers — including some parents desperate for a cure for their autistic children — will still find a way to access false information.

"Content moderation can really help curb what informs the decisions that people make," said Nat Gyenes, a program lead at the social technology firm Meedan, who also studies technology and health at Harvard's Berkman Klein Center for Internet & Society. “But at the same time, people who want or are determined to look for other misinformation will find it on the internet.”

Laurel Austin is so determined. In her spare time, she dabbles in conspiracy theories, co-hosting or appearing in anti-vaccination radio programs and videos — several with Rivera herself. According to her social media posts, Austin is also a “flat-earther” and attends annual conferences with other enthusiasts of the unscientific idea that the world is not a globe.

The anatomy of an investigation

Joshua was visiting his dad overnight in January when his stepmother, retired registered nurse Kerrie Austin, opened the bottle his mother had sent along with directions for him to take a shot glass full of the solution every two hours, from 7 a.m. to 9 p.m.

The smell of chlorine “almost knocked me off my feet,” Kerrie Austin said.

Bradley Austin called poison control, then took the solution to the Lenexa police department and Joshua to the hospital for blood tests, which came back normal. In the police investigation notes that Bradley Austin shared with NBC News and that were confirmed by a police spokesman, the Lenexa police officer wrote that he “could smell the overwhelming odor of bleach.” Another officer wrote that the bottle was “off-gassing.” “The gassing smelled like chlorine and was very potent.”

As part of their investigation, a police officer called Kansas’ poison control center and spoke to a pharmacist, who said that he was familiar with the chlorine dioxide solution and advised the officer that it was unsafe to consume, according to investigation notes.

That awareness likely came from experience. Over the last five years, poison control centers have managed 16,521 cases nationwide dealing with chlorine dioxide, according to data provided by the American Association of Poison Control Centers. At least 50 of the cases were considered life-threatening, and eight people died. It’s not clear how many of the cases involved people with autism.

According to the investigation notes, after speaking to Bradley Austin, the officers went to Laurel Austin’s home. She told the officers that she was following Rivera’s chlorine dioxide protocol and said she’d seen improvement in her sons’ behavior since she began giving them the solution. The police observed both Joshua and Jeremy and determined they seemed to be happy and in good health and neither appeared to be in pain.

Laurel Austin showed the police online articles about chlorine dioxide, including one from the Autism Research Institute, one of the first and most vocal organizations to push the discredited theory that vaccines cause autism. That 2015 article claimed the solution had the potential to heal, but ultimately advised against its use, according to investigation notes. “This legitimizes the claim by Laurel of her use of MMS CLO2 as a holistic treatment approach,” the officer wrote. Laurel Austin followed up with the officer by sending a link to a YouTube video of Rivera explaining the chlorine dioxide protocol.

According to the notes, the officers were also convinced by a document labeled “Jeremy Austin’s Daily List of Supplements.” One line of the document read: “MMS Chlorine Dioxide (CD/MMS) drops 16 doses a day every hour.” The list was stamped and signed by Dr. Sarita Singh, a primary care physician at Kansas University’s MedWest Family Medicine Clinic.

Officers spoke to Singh, who confirmed she had approved the list of supplements, including the chlorine dioxide. After a follow-up visit with Laurel Austin and Joshua, Singh sent a letter to police stating the chlorine dioxide was “benign and not toxic,” according to the investigation notes.

Singh is currently on maternity leave and did not respond to requests for comment. Jill Chadwick, director of media relations for the University of Kansas Health System, which oversees Singh’s practice, cited privacy laws in an email declining comment.

“But even if you called the mom and got her to sign a waiver enabling us to talk,” Chadwick wrote, “We have nothing to add to this story at this time.”

In a YouTube video posted in March, Laurel explained how she found medical doctors willing to sign off on the chlorine dioxide protocol. “Actually, I have found several doctors. Just by going to the Institute for Functional Medicine website and you put in your area, and they can bring up doctors that you didn't even know were there.”

The Institute for Functional Medicine is a professional association focused on alternative medicine, which it describes as “an individualized, patient-centered, science-based approach that empowers patients and practitioners to work together to address the underlying causes of disease and promote optimal wellness.” It operates as a nonprofit and brought in $16 million in revenue in 2017.

Doctors have criticized the organization’s promotion of vitamins, probiotics and parasite cleanses in treatments for various illnesses without scientific evidence that they work. The founder of the institute has bucked medical consensus with the claim that autism is caused by toxins in the environment and can be cured with changes to diet and supplemental nutrition.

“IFM does not support the use of chlorine dioxide nor do we include that biochemistry in our programs,” Institute for Functional Medicine CEO Amy Mack wrote in an email to NBC News. “We have concerns regarding potential side effects.”

There are 12 practitioners listed in the IFM database in Laurel Austin’s area, according to a search on the association’s website. Singh is not among them.

“I have so far found three doctors that will sign off on this,” Laurel Austin said in the video. “And to say that they use it, too.”

‘No evidence of a crime’

Bradley Austin’s call wasn’t the first time someone had reported Laurel Austin’s treatment of her sons to the police. Last November, a staff member at Options Services, a day program for people with developmental disabilities in Merriam, Kansas, called police to report that Laurel Austin had given Jeremy chlorine dioxide in the parking lot after staff members refused to do so. Laurel Austin described that incident to police as part of the January investigation.

Laurel Austin responded by leaving a negative review in April on the organization’s Google page. In the review, she wrote that she was “blindsided” by the center calling the police when she had a doctor’s note supporting the use of chlorine dioxide. But, she continued, “All the stress and anxiety finally ended today when 5 months later I have 2 more doctors signing off on this protocol AS SAFE.”

The owner of Options Services did not return a phone call requesting comment, but did respond to the Google review.

“I'm sorry you are unhappy that we contacted the police as directed to by Poison Control for forcing your son to drink bleach,” the owner replied in April, adding that Jeremy had been vomiting and the smell of the solution was making employees sick. “What you force your son to do on your time is most certainly your business but we will not be put in a position of contributing harm to anyone.”

Options Services’ report triggered an investigation by Kansas Adult Protective Services, according to the police records. A caseworker visited Laurel Austin’s home, looked at the chlorine dioxide bottle and the doctor’s note and made contact with Jeremy, noting that he didn’t appear to be presenting any negative side effects. “Although the MMS protocol is controversial, it did not meet the threshold to remove” Laurel Austin’s sons, the caseworker found, according to the police report.

A representative for Kansas Adult Protective Services declined to comment, citing privacy laws.

After talking with Poison Control, Adult Protective Services and the doctor, the Lenexa police closed their investigation. “There was no legal standing to feel they were in any immediate danger,” the report found.

“We concluded our case with no evidence of a crime,” Danny Chavez, Lenexa Police Department’s public information officer, said.

Chavez said police hypothetically could have brought charges if Laurel Austin had been feeding her sons something like gasoline, but when it comes to chlorine dioxide, “we don't have evidence that it is a super dangerous poison.”

“Ultimately what we have to look at is, is there the intention to commit a crime? Whether something is a good practice and whether something rises to the level of a crime are two separate things.”

Bradley and Kerrie Austin do not speak to Laurel Austin and have not seen or heard from Jeremy or Joshua since the police closed the case in January. Although they pay child support, they have no legal rights to the young men because they are not listed as guardians.