Determination of some polybrominated flame retardants in biota, sediment and sewage sludge

Detta är en avhandling från Stockholm : Stockholm University

Sammanfattning: Brominated flame retardants (BFRs) are mainly used in different polymers, and can be released to the environment during industrial processes, during the entire life-time of the flame-retarded product and after disposal. The aim of the present study was to gain knowledge about occurrence and concentrations of some BFRs in the environment, to search for sources for these chemicals and to investigate changes in concentrations over time. The emphasis was on the polybrominated diphenyl ethers (PBDE), but hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA) were also studied to some extent.The analytical method used was mass spectrometry run in the electron capture negative ionisation (ECNI) mode. The formation of bromide ions was utilised as a sensitive and selective detection method for the brominated compounds.BFRs seem to be ubiquitous contaminants in the environment. Long range transport in air may explain the contamination of PBDE in whitefish from the pristine mountain lake Storvindeln. The highest concentrations are found in samples collected in the vicinity of industrial (textile and polymer) activities, where they are/have been used. Samples from heavily populated areas contain higher concentrations of PBDE than samples from remote areas, which results in a south-north geographical trend in concentrations. Generally the concentrations are higher in aquatic organisms than in those from terrestrial environments. Municipal sewage sludge, which reflects the current use of chemicals in society, contains all the BFRs covered in this thesis.DecaBDE was only indicated in biota, but was found in high concentrations in sediment. Higher concentrations of tetra- and pentaBDE in piscivorous birds and mammals compared to the fish they eat indicate biomagnification of these substances. HBCD was found in both fish and sediment from the Rivers Viskan/Häggån, where it has been used to some extent as a substitute for decaBDE in the textile industry. HBCD was also detected in guillemot eggs from a background area in the Baltic Sea.Increasing concentrations over time of tetra- and pentaBDE was first indicated in a sediment core from the Baltic Sea, sampled in 1987. This increase was later confirmed in guillemot eggs from the island Stora Karlsö in the Baltic, but from the mid-late 1980s, the concentrations started to decrease in this species. This decrease is not in agreement with the results from other studies, indicating different sources of contamination.

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