If you closely examine your living room couch, your favorite easy chair or your child’s car seat, the odds are strong that you will find upholstery that is filled with polyurethane foam treated with a chemical flame retardant. Some may find that comforting: Isn’t it desirable to hold an accidental fire at bay, one caused by, say, a burning cigarette or faulty electrical wiring? But studies show that many flame-resistant chemicals loom as potential health menaces, associated with cancers, memory loss, lower I.Q.s and impaired motor skills in children, to name a few woes. Isn’t it just as desirable, some would also say, to keep such substances out of people’s lives?

On the surface, this may seem like a struggle between worthy goals of equal merit: forestalling household fires on one hand, preventing toxic contamination on the other. But this new installment of Retro Report, a series of video documentaries examining major news stories of the past and their consequences, suggests that the surface impression presents a false equivalence. Health risks linked to some of these chemical compounds have been growing while their fire-deterring value has been called into serious doubt.

To frame the issue, the video goes back to the early 1970s and a controversy that older Americans may recognize from a single word: Tris. Chemists know it as Tris(2,3-dibromopropyl) phosphate. Under the shorter sobriquet, it gained national fame as a flame retardant in children’s pajamas. Its purpose was to buy precious seconds that, in a fire, might spell the difference between survival and death.

But fame turned to notoriety later that decade when research by two scientists, Arlene Blum and Bruce N. Ames, concluded that Tris is a mutagen, a gene-altering agent. The federal Consumer Product Safety Commission, a new agency in the ’70s, promptly prohibited its use in the sleepwear. Even though the courts then struck down the ban, children’s clothing manufacturers in effect enforced it by agreeing to keep that form of Tris out of their products. They then did the same with a new version of the compound, chlorinated Tris. But chlorinated Tris itself was never banned. As time passed, it made its way, along with an array of other chlorinated and brominated flame retardants, into the furniture found in most American homes.