New study shows that replacement chemicals for banned flame retardants are not proven safe
A number of halogenated flame retardants are no longer manufactured or used because they present a hazard to human and environmental health. In some cases, non-halogenated chemicals promoted as safer alternatives are used as replacements. But according to a new study, the non-halogenated alternatives may not be much of an improvement.
The study considered 13 non-halogenated chemicals of the following types:
- Inorganic (6)
- Organophosphorus (5)
- Nitrogen-based (1)
- Intumescent system (1)
The authors evaluated available data on three widely accepted criteria used to judge if a chemical is safe: Persistence in the environment, ability to Bioaccumulate (build up in animals), and Toxicity. These are known as the PBT criteria.
Only one of the chemicals, the organophosphorus compound triphenyl phosphate (TPP), had enough studies to draw conclusions and the news isn’t good. TPP is persistent, bioaccumulative, and toxic. It’s been found in air, water, soil, and animals and its breakdown product has been detected in human urine. It is labeled “dangerous to the environment” by the European Chemicals Agency (ECHA) due to its aquatic toxicity.
TPP is one of the ingredients in Firemaster 550, a new flame retardant mixture whose use has increased greatly since 2005. Exposure to Firemaster 550 was linked to obesity and anxiety in one study on rats.
The devil you know for the one you don’t
All of the other chemicals are so poorly studied that the authors couldn’t draw definite conclusions. On the bright side, several of the inorganic compounds appeared promising as safer replacements. In contrast, all of the organophosphorous compounds warrant concern based on the known data. Indeed, the U.S. National Toxicology Program currently has a number of chemicals in this class under study due to their structural similarities to known toxicants and the high risk of exposure to children.
Unfortunately, many of these replacement chemicals are in widespread use, despite the known toxicity in the case of TPP and the large data gaps in safety information for the others. This study highlights the problems with our current system of chemical regulation that allows substitution of one harmful chemical with another, without demonstration that the replacement is better.