At present, the data of health effects of brominated flame retardants are mainly from animal experiments. In experimental animals, some flame retardants affect the liver, nerve, immune, endocrine system and so on. However, the dosage of these benefits is often much higher than the content of flame retardants in the environment. For the currently approved flame retardants, no obvious threat to human health has been found in the risk assessment of environmental exposure.
Green environmental protection
For tetrabromobisphenol A, the largest brominated flame retardant currently used, the European Chemicals Bureau pointed out in its assessment report that it had not been found to be harmful to human health. In 2011, the European Food Safety Authority (EFSA) assessed the risk of tetrabromobisphenol A entering food through the environment and concluded that there was no health risk from dietary exposure and that exposure to indoor dust was unlikely to cause concern. Similar conclusions have been reached in the evaluation of PBBs and PBDEs.
At present, only hexabromocyclododecane (HBCD) is recognized as persistent organic pollutants (POPs) by the United Nations Environment Programme (UNEP) in the market of brominated flame retardants, and will be phased out gradually. Other flame retardants identified as persistent organic pollutants (such as pentabromodiphenyl ether and octabromodiphenyl ether) have been discontinued earlier.
Considering environmental and health risks, the use of several brominated flame retardants has been limited by governments. In addition to hexabromocyclododecane, the RoHS Directive of the European Union limits the use of PBBs and PBDEs as brominated flame retardants in electronic appliances. The United States prohibits the use of PBBs. In China's Regulations on Pollution Control of Electronic Information Products, restrictions are also imposed on PBBs and PBDEs. However, it is noteworthy that no country supports the complete ban of brominated flame retardants. In addition to the above varieties, brominated flame retardants are still widely used in various countries in the world.
In addition, with the progress of technology, the emergence of new brominated flame retardants can further reduce the risk. For example, some companies have developed macromolecular polymeric brominated flame retardants to replace hexabromocyclododecane used in building thermal insulation materials. The polymer flame retardant has a large molecule and is difficult to penetrate the cell membrane, thus avoiding the influence of entering the organism.