BERKELEY, CALIF. (Nov. 26, 10:50 a.m. ET) — U.S. researchers are calling for U.S. building codes to be changed, following a study that claims to show that mandatory flame retardants routinely added to foam insulation are not only harmful to human health and the environment, but also make no difference to the prevention of fire in buildings where a fire-safe thermal barrier already exists, reports Science Daily.

Science Daily says the researchers, from centers including the University of California and the Lawrence Berkeley National Laboratory, have assessed fire safety literature since the mid-1970s.

They conclude, according to the report, that the addition of halogenated organic compounds to plastic insulation materials such as polystyrene, polyisocyanurate and polyurethane is costly, ineffective and environmentally damaging.

These conclusions are published in the latest issue of the journal Building Research and Information.