YouTube has reportedly taken down hundreds of videos which contain false claims drinking industrial-strength bleach can cure autism.
Millions of people had watched the clips, Business Insider reports, which also claim sodium chlorite can cure malaria, cancer and even AIDS.
But it can also kill.
"People who were just looking for broad information on autism or malaria were being pushed these videos," Business Insider reporter Tom Porter told BBC News.
Many of the videos were created by former Scientologist Jim Humble and others linked to his group Genesis II, which claims to be a "church of health and healing".
Since the 1990s, Humble has been promoting sodium chlorite under the name 'Miracle Mineral Solution' (MMS). When added to citric acid, it creates chlorine dioxide - a strong bleach and effective pathogen killer, but also a deadly poison.
New Zealand's MedSafe agency issued a warning against using MMS in 2010, calling it "a potent bleach used for stripping textiles and industrial water treatment", and warned anyone intending to ingest it to immediately throw away their supplies.
"High oral doses of this bleach, such as those recommended in the labelling, can cause nausea, vomiting, diarrhoea and symptoms of severe dehydration."
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Porter said it was "shocking" to find so much dangerous misinformation on the world's most popular video site.
YouTube told Business Insider it removes harmful content when users report it.
"Misinformation is a difficult challenge and any misinformation on medical topics is especially concerning," the site, owned by Google, said in a statement.
"We've taken a number of steps to address this including surfacing more authoritative content across our site for people searching for related topics on YouTube.
"However, our Community Guidelines prohibit content intended to encourage dangerous activities that have an inherent risk of physical harm, and we work to quickly remove flagged videos that violate these policies."
Despite the crackdown, Newshub was able to find videos on YouTube praising the substance - some even recommending it be inserted anally for the best results.
"Autistic children have to drink this up to 16 times a day then are subjected to six enemas of this bleach product daily, and the side effects are horrific," autistic rights campaigner Fiona O'Leary told Business Insider.
Posts on closed Facebook groups Business Insider got access to back that up. Parents asking other members why their children are coming out in rashes, vomiting and having seizures are told by moderators they're all part of the detoxing process. In some cases parents are reportedly told to up the dosage.
Bishop Roger Blake of Genesis II's New Zealand branch said there had been no studies showing chlorine dioxide to be harmful.
"Those attacks are unfair but they're not unexpected when the media is owned by a corrupt, criminal organisation that have got a lot of unhuman things in mind," he told Newshub.
He went on to claim vaccines cause autism and accuse Newshub of airing "several fake news items every night".