Determination and comparison of polybrominated diphenyl ethers in primary, secondary, and tertiary wastewater treatment plants

Abstract

A concurrent comparison of the concentration, occurrence, and removal efficiency of polybrominated diphenyl ethers (PBDEs) in wastewater from primary, secondary and tertiary wastewater treatment plants was examined. The study area was composed of all three types of wastewater treatment plants in two countries, the United States of America and Mexico. Nineteen PBDEs were analyzed by an environmentally friendly technique, Stir Bar Sorptive Extraction coupled with thermal desorption and gas chromatography and mass spectrometry. This method required no organic solvent and was proven to be effective and sensitive. The most detected PBDEs found in wastewater influent and effluent were BDE-47, BDE-99, BDE-100 and BDE-119. The total concentration of PBDEs (∑BDE47,99,100,119) in the influents ranged from 115.3 to 595.0 ng L−1, and from below method detection limit to 388.2 ng L−1 in the effluent. It was observed that tertiary treatment was the most effective process to remove BDE-47, 99, and 100, while the primary treatment only rendered an average of 27% removal of total PBDEs. Owing to the incomplete removal in wastewater processes, PBDEs are constantly released into the environment, which implies possible hazardous effects on the environment and human health.