Landfills and waste water treatment plants as sources of ... - GKSS

INTRODUCTION
Mabury 2006). This increase is probably related to the withdrawal of PSOF-based products by
the 3M Company (Stock et al. 2004).
Since the 1960s, PBDEs are produced by bromination of diphenyl ether in the presence of an
Friedel-Craft catalyst in a solvent (Alaee et al. 2003). The bromination process is fairly
specific due to the directing oxygen atom and steric hindrance, resulting in a limited number
of PBDE congeners. Therefore, commercial formulations that are manufactured contain
specified congeners of brominated diphenyl ethers (BDEs) (Rahman et al. 2001). Commercial
pentaBDE mixture usually consists of BDE47 (24- 38 %), BDE82, BDE85, BDE99, BDE100
(50- 62 %), BDE153 and BDE154 (4-8 %). OctaBDE mixtures comprise congeners BDE153,
BDE154 (10-12 %), BDE183 (43-44 %), octaBDE (31-35 %) and nonaBDE (9-11 %) as well
as around 1 % of BDE209. In contrast, decaBDE is predominantly composed of BDE209 (97-
98 %) with small amounts of nonaBDE (Darnerud et al. 2001).
In general, the use of PBDEs as flame retardants is in relation to their bromination level.
PentaBDE mixtures are mainly added to polyurethane foams (PUF). PUF are applied to car
interiors, carpets, furniture and pillows (Prevedouros et al. 2004). Furthermore, small amounts
of pentaBDE have been applied to electronic housings, textiles and packaging. In contrast,
highly brominated mixtures such as octa- and decaBDE are almost entirely used in dense
thermoplastics, such as television and computer housings (Hale et al. 2002; Alaee et al. 2003).
The worldwide consumption of PBDEs in 2001 was 67000 t (Watanabe 2003). DecaBDE
accounted for 83 % whereas pentaBDE and octaBDE account for a smaller proportion with
12 % and 5 %, respectively (Watanabe 2003). In 2003, the production volume of decaBDE
mixture was estimated to be 56000 t (Christiansson et al. 2009). The usage of PBDE products
differ considerably between the continents. Compared to North America, Europe and Asia
have rather low consumption of penta- and octaBDE mixtures (Kierkegaard et al. 2009). In
contrast to PFCs, estimates on the historical production of PBDEs are very limited. However,
Prevedouros et al. (2004) calculated the European production and consumption of pentaBDE
from 1970 to 2000 between 3000 and 5000 t. Furthermore 9000 to10000 t were imported in
finished products. Starting in 1980, consumption of pentaBDE increased rather constantly to
1200 t in the mid of the 1990s. From thereon, a rapid decline to about 200 t in 2000 was
estimated. Overall, production in North America and Europe is about to decline, due to
voluntary and restrictive phase-outs (see section 1.4.6) of octa- and pentaBDE (and partly
decaBDE) (de Wit et al. 2009).
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