PNNL

Abstract

A new method was developed for rapid and direct measurement of aqueous polybrominated diphenyl ethers (PBDEs) using fluorescence spectroscopy. The fluorescence spectra of aqueous tri- to deca-BDE (BDE28, 47, 99, 153, 190 and 209) that are commonly found in environment were determined at variable emission and excitation wavelengths. The results revealed that the PBDEs have distinct fluorescence spectral profiles and peak positions that can be exploited to identify these species and determine their concentrations in aqueous solutions. The detection limits as determined in deionized water spiked with PBDEs are 1.71-5.82 ng/L for BDE28, BDE47, BDE190 and BDE209, and 45.55-69.95 ng/L for BDE99 and BDE153. The effects of environmental variables including pH, humic substance, and groundwater chemical composition on PBDEs measurements were also investigated. These environmental variables affected fluorescence intensity, but their effect can be corrected through linear additivity and separation of spectral signal contribution. Compared with conventional GC-based analytical methods, the fluorescence spectroscopy method is more efficient as it only uses a small amount of samples (4 ml), avoids lengthy complicated concentration and extraction steps, and has a low detection limit of a few ng/L.