Occurrence and distribution of tetrabromobisphenol A and its derivative in river sediments from Vaal River Catchment,South Africa

Brominated flame retardants(BFRs)compounds have been widely added in a number of products to reduce their flammability.In the present study,the concentrations and distribution of tetrabromobisphenol A(TBBPA)and its derivatives,i.e.tribromophenol dibromopropyl ether(TBPDBPE),tetrabromobisphenol A bis-dibromopropyl ether(TBBPA BDBPE),tetrabromobisphenol A bis-allyl ether(TBBPA BAE)were investigated in sediment samples collected from the Vaal River catchment,South Africa.The results showed that all these pollutants were detected in sediments with TBBPA BAE being the most abundant contaminant.The TBBPA BAE concentrations ranged from 3.5 to 44.4 ng/g(mean 16 ng/g)while the concentration ranged from not detected(nd)to 2.4 ng/g(mean 0.6 ng/g),nd-21.0 ng/g(mean 6 ng/g)and nd-2.0 ng/g(mean 0.2 ng/g)for TBPDBPE,TBBPA and TBBPA BDBPE;respectively.Higher concentrations of these pollutants were found in sampling sites receiving effluents of wastewater treatment works(WWTWs)treating some industrial wastewater suggesting effluents might play an important role in the contamination of BFRs in the environment.Negative correlation between TBBPA and TBBPA BAE was observed implying different sources or environmental fates between these pollutants.Overall,the results showed a need for further studies to be undertaken in investigating the presence,fate and sources of alternative halogenated flame retardants in the environment.