Flame retardants (FRs) are used in everyday products such as furniture and electronics to provide fire protection. The intensive use of FRs has led to their wide spread in the environment. Many chemicals have been found to have bioaccumulative, persistent and toxic properties which have led to a ban of some of these FR compounds based on international agreements. For example, Penta- and octa-polybrominated diphenyl ethers (BDEs) have been included in the Stockholm Convention. However, most FRs are not restricted, and in many cases it is not known to which extent they are used or to which degree they are polluting the environment. The aim of this study was to provide a snapshot of the current FR pollution in Swedish rivers and streams. In total, 25 rivers and streams were sampled along the east coast of Sweden from north to south. The sampling was done in October 2013 and results from this pre-study were presented previously (Ahrens et al. 2014). Since then, the analytical method for FRs has been improved, and here we report on the re-analysis of the extracts from the previous study.
In total 61 (including 7 PBDEs, 35 AFRs, 19 OPFRs), mainly novel FRs, were included in the analytical method. The highest number of FRs was detected in Nyköpingsån (22) and Indalsälven (16). The most frequently detected FRs were ∑tris(1,3-dichloroisopropyl) phosphate/tris(2-ethylhexyl) phosphate) (ΣTDCIPP/TEHP, quantified as the sum of both) detected in all 25 samples from north to south, followed by tris(2-chloroethyl) phosphate (TCEP) (detected in 15 samples) and tetrabromobisphenol-A (TBBPA) (detected in 11 samples). The highest FR concentrations were observed in Nyköpingsån, Fyrisån and Indalsälven with ∑FR concentrations of 240, 230 and 140 ng L-1, respectively. It is evident that FR concentrations in general are higher in the south than in the north, likely explained by the higher population density in the south. Daily loads of ∑FRs transported from Swedish rivers into the Baltic Sea were estimated to be in total 15 kg/day. Indalsälven and Nyköpingsån showed highest total daily loads with 5.2 and 4.9 kg/day, respectively. The composition profiles of these two rivers showed a similar pattern with 3,4,5,6-Tetrabromophthalic anhydride (TEBP-Anh, ~30% of the ∑FR), Tetrachlorobisphenol-A (TCBPA, ~23% of the ∑FR) and TBBPA (~30% of the ∑FR) as the major FRs indicating that these are the three main FRs transported into the Baltic Sea from Swedish rivers.
Since this study only provides a snapshot of current conditions, care needs to be taken in the interpretation of the results. This type of screening study is, however, useful for getting a general idea on pollution levels and revealing of tentative hot spots. For better insight into the pollution situation, another sampling strategy is neded, e.g. covering longer time periods (and different seasons) and using more frequent sampling or time/flow-proportional sampling.
Products Used in this Publication
PBCH
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