A group calling itself Genesis II Church of Health and Healing plans to convene at a hotel resort in Washington state on Saturday to promote a “miracle cure” that claims to cure 95% of all diseases in the world by making adults and children, including infants, drink industrial bleach.

The group is inviting members of the public through Facebook to attend what they call their “effective alternative healing” at the Icicle Village Resort in Leavenworth on Saturday morning. The organizer of the event, Tom Merry, has publicized the event on his personal Facebook page by telling people that learning how to consume the bleach “could save your life, or the life of a loved one sent home to die”.

The “church” is asking attendants of the meeting to “donate” $450 each, or $800 per couple, in exchange for receiving membership to the organization as well as packages of the bleach, which they call “sacraments”. The chemical is referred to as MMS, or “miracle mineral solution or supplement”, and participants are promised they will acquire “the knowledge to help heal many people of this world’s terrible diseases”.

The ‘sacramental kit’ sold by Genesis II Church of Health and Healing is referred to as MMS, or ‘miracle mineral solution or supplement’. Photograph: https://g2sacraments.org/

In fact, MMS consists of chlorine dioxide, a powerful bleach that is used both on textiles and in the industrial treatment of water. It has been banned in several countries around the world for use as a medical treatment.

In the US, the chemical cannot be sold for human consumption. In 2010, the US Food and Drug Administration (FDA) put out a public warning after it was notified of many injuries to consumers from drinking the fluid, with symptoms that included nausea, vomiting, diarrhea, severe dehydration and one person who had a life-threatening reaction.

The FDA issued the blunt advice: “Consumers who have MMS should stop using it immediately and throw it away.”

A spokesman for the FDA told the Guardian that the agency could not comment on possible civil or criminal law enforcement actions, but added: “The FDA continues to advise consumers about the dangers of Miracle Mineral Solution and the agency has issued warnings to consumers over the past decade.”

The headline attraction of Saturday’s event in Leavenworth is Mark Grenon, a self-appointed “bishop” of the Genesis II Church. He is author of a book titled Imagine A World Without Dis-Ease: Is It Possible?

In a video posted on the “church’s” website, Grenon says that the “sacramental protocols” sold by the group can eliminate 95% of the world’s diseases, including malaria, ebola, dengue fever, all types of cancer, diabetes, autism, HIV and multiple sclerosis. It sells 4oz bottles of sodium chlorite as “sacramental cleansing water” for $15, giving instructions on how to mix it with citric acid to make chlorine dioxide.

The Guardian contacted Grenon to ask why he was peddling industrial bleach described by the FDA as potentially dangerous as a miracle cure, but he did not immediately respond.

As promotion for the event, Merry has posted on Facebook a link to a video which claims to show people with malaria being cured in two hours. The video shows a British advocate of MMS travelling to a village in Uganda where he arranges for several villagers to be given the “miracle cure”.

One of the victims shown in the film is an infant lying in his or her mother’s arms who is made to drink a cup of the bleach. The child screams as the fluid is swallowed.

The Guardian tried to contact both Merry and the Icicle Village Resort, but neither responded.

Fiona O’Leary, a campaigner against pseudo science whose work helped to get MMS banned in Ireland in 2016, said she was horrified that the Genesis II Church, which she called a “bleach cult”, was hosting a public event in Washington.

“This event is endangering people’s lives, especially children. We must protect vulnerable people from this dangerous quackery,” she said.

This is not the first time that Washington state has grappled with a group touting MMS. In 2015 Louis Smith from Spokane was convicted in the Eastern District of Washington for selling misbranded drugs and defrauding the US. He had sold MMS through a website called Project GreenLife, having obtained sodium chlorite fraudulently by creating a phony “water purification” business.

He was sentenced to four years in prison.