Concentrations and sources of an emerging pollutant, decabromodiphenylethane (DBDPE), in sewage sludge for land application

The presence of an emerging brominated flame retardant, decabromodiphenylethane (DBDPE), has been confirmed in Spanish sewage sludge. Thirty one samples from different urban wastewater treatment plants (WWTPs) were analyzed for this brominated flame retardant. DBDPE was positively identified and quantified in all samples at lower concentrations (47.0 ± 29.7 ng/g dry weight (dw); mean ± SD) than those obtained for decabromodiphenyl ether (BDE-209) (290 ± 236 ng/g dw; mean ± SD) in a previous study. Influence of the WWTP characteristics in the pollutant levels was evaluated. No significant correlations were obtained between DBDPE concentrations and the population or sewage sludge production rate associated with the plants, neither wastewater treatment method. Sources of DBDPE in the sludge were also evaluated. Data indicate a common origin for DBDPE and BDE-209, which may be related to leaching processes during the use and disposal of consumer products containing these chemicals. Nevertheless, DBDPE contents are not influenced by industrial activities, which suggests that the infusion of DBDPE commercial mixture is not a source of this chemical into the environment, and indicates that the use of DBDPE in the Spanish industry is still low compared to deca-BDE.