In recent years, some of these compounds were shown to have harmful effects on the environment, causing them to be replaced by more eco-friendly alternatives.

However, a new study in ACS' journal Environmental Science & Technology, indicates that heat or ultraviolet light could break down a "safe" flame retardant into potentially harmful compounds.

Some brominated flame retardants, such as hexabromocyclododecane (HBCD), persist and bioaccumulate in the environment, potentially having toxic effects on organisms.

A replacement for HBCD, polymeric flame retardant (polyFR) is a large polymer that it is much less likely to enter cells or accumulate in the food chain.

Although polyFR is considered a more environmentally friendly flame retardant, the long-term behavior of the chemical is unknown.

So Christoph Koch, Bernd Sures and colleagues examined whether heat or ultraviolet light -- which could be encountered during the product's use as insulation in a hot attic or after its disposal in an open landfill -- could break down polyFR into smaller, potentially more harmful substances.

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