Are you sitting down? Before you do, think about your couch, because it could be killing you.

Since 1975, in an effort to curb the number of lives lost in house fires, all furniture has been required to contain flame retardants. But these toxic substances — among the 84,000 chemicals in our products that are untested and unregulated — are dangerous to human health, causing an increased risk of cancer, mental problems and birth defects. This point is chillingly driven home in the documentary “Toxic Hot Seat,” which will premiere on HBO on Nov. 25.

Filmmakers James Redford and Kirby Walker interviewed chemists, journalists, firefighters, politicians, and activists to uncover the truth behind this issue and how chemical companies and their lobbyists have spent millions to cover it up.

Initially, “We really thought it was going to be a story about legislation, how we could follow that and demonstrate whether there was progress and if not, why,” said Redford (the son of actor and environmental activist Robert Redford). “That approach crashed and burned rapidly,” when they discovered three months into the project that the Chicago Tribune was working on a five-part series about the issue called “Playing With Fire,” and the journalists behind it agreed to be part of the documentary. “It required a lot of steps to get permission, but it really changed the complexion of the film.”

Walker added that when they’d first heard stories about the chemical company cover-ups involving “front” groups and the tobacco industry, it smacked too much of conspiracy theory to be true. “We thought, ‘it can’t be this bad.’ But the Tribune found that it was indeed that bad, and we did include it. A democracy can’t function if the people who live in it don’t know the truth. Because of investigative journalism, we’re told what is happening and can advocate for ourselves. That really resonated with us.”

The film depicts the impact these chemicals have had on firefighters, who have unusually high rates of cancer due to toxic chemical exposure, and via experiments, demonstrates the ineffectiveness of fire retardants. Dr. Vytenis Babrauskas, who published a study on the subject in 1987, asserted in the Tribune article that the amount of retardants in a typical home’s furniture provides “little to no fire protection.”

No wonder a large portion of the film focuses on efforts to change laws. Many states are considering legislation now, and in January, a new regulation will take effect that makes fire retardants no longer mandatory. Manufacturers don’t have to include the chemicals, but still can, so the onus is on the consumer to ask questions and buy accordingly.

“We want people to demand change and reform.  If enough people see this we can demand change in Washington,” Walker said. Added Redford, “My hope is everybody talks about it, gets on social media. If we speak up we can get these chemicals out of our lives. We can’t get rid of these couches with chemicals in them overnight, but it’s really about thinking ahead for our children. We act with our pocketbooks and it can really make a difference.”

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