Qualitative and quantitative analysis of selected brominated flame retardants in plastics of the building and construction sector

Abstract

Brominated flame retardants (BFRs) have been used in plastics since the 1960s. Several are listed as persistent organic pollutants (POPs) under the Stockholm Convention due to their persistence, toxicity, bioaccumulation and/or mobility. Owing to long service lifetimes, substantial stocks of POP-BFRs, such as polybrominated diphenyl ethers (PBDEs), are still in use, yet construction plastics have rarely been systematically screened for these compounds. Around 1200 construction plastic waste samples from twelve product categories were screened by X-ray fluorescence spectroscopy. From these, 15 mixed samples derived from 118 bromine-rich samples (≥0.5 wt%) were analysed by liquid and gas chromatography–mass spectrometry to identify regulated and emerging BFRs and to assess their contribution to total bromine content. In total, 19 flame retardants were targeted, including 3 PBDE technical mixtures, Dechlorane Plus, and 15 additional BFRs. PBDEs and the POP candidates decabromo-diphenyl ethane (DBDPE) and bis(2-ethylhexyl) tetrabromophthalate were detected. Elevated PBDE concentrations (2.3-2.6 wt%) occurred in only two samples, whereas DBDPE was found in 11 of 15 samples across four product categories. As DBDPE was introduced during the 1990s as a substitute for commercial decaBDE, these materials likely represent more recent stocks and resulting waste streams. Given that construction plastics typically remain in use for half a century, large volumes of materials containing PBDE and DBDPE remain in use. As DBDPE continues to be incorporated into new products, stock levels are consistently rising. The findings demonstrate that both legacy POPs and emerging replacement BFRs persist in construction plastics, complicating waste management and plastic recycling.