Background and aims
Hexabromocyclododecane (HBCD) is a brominated flame retardant used mainly in polystyrene foam as well as in textile applications. In recent years, measures were taken to reduce HBCD emissions during its production and use. To evaluate the efficacy of these measures, a monitoring project was initiated with fish as bioaccumulation indicators.
Since 2007 bream was sampled annually at several European freshwater sites applying standardized methods. Muscle samples were analyzed by a validated liquid chromatography–tandem mass spectrometry (LC-MS/MS) method which allows the quantification of a-, ß-, and ?-diastereomers of HBCD.
In most samples, a-HBCD was predominant. The lowest HBCD levels (11 µg/kg lipid weight (lw), sum of three HBCD diastereomers) were detected in bream sampled in 2009 from Lake Belau which is situated in a rural area of Northern Germany. During the 4-year study period, statistical significant decreases of HBCD concentrations were detected in bream from the rivers Rhone (France; -85%, level 2010, 205 µg/kg lw) and Western Scheldt (the Netherlands; -60%, level 2010, 36 µg/kg lw). High HBCD concentrations (9,480–14,500 µg/kg lw) without a clear time trend were observed in bream from the river Tees (UK). These high levels are in line with published data for fish from contaminated regions.
Overall, the results indicate that environmental burdens of HBCD are decreasing at those locations where point sources and more diffuse emissions are expected.