Estrogen-like endocrine disrupting compounds (EEDC) such as bisphenol A, nonylphenol, and phthalic acid esters are toxic compounds that may occur in both raw- and drinking water. The aim of this study was to combine chemical- and bioassay to evaluate the risk of EEDCs in the drinking water treatment plants (DWTPs). Fifty-six samples were collected from seven DWTPs located in northern-, central-, and southern Taiwan from 2011 to 2012 and subjected to chemical analyses and two bioassay methods for total estrogenic activity (E-Screen and T47D-KBluc assay). Among of the considered EEDCs, only dibutyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP) were detected in both drinking and raw water samples. DBP levels in drinking water ranged from
A green technique was designed for assessing toxic equivalence (TEQ) levels of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in sediments and soil from dioxin-contaminated areas. This technique combines a fast cleanup system with a dioxin-responsive-element (DRE)-driven luciferase bioassay. Samples from sediment (n = 10) and soil (n = 11) were analyzed with the technique; levels of PCDD/Fs ranged from 75.1 to 2,670 ng DRE-driven luciferase activity (DL)-TEQ/kg dry weight (d.w.). Significant correlations were found between DL-TEQs (by the bioassay) and PCDD/F WHO-TEQs (by HRGC/HRMS). DL-TEQs is significantly correlated with WHO-TEQs of 2,3,7,8-TCDD and 1,2,3,7,8-PeCDD using a multiple stepwise linear regression model (adjusted R(2) = 0.962, p < 0.001).
This study investigates the emissions of polycyclic aromatic hydrocarbons (PAHs) from a single hydrogen-oxygen proton exchange membrane (PEM) fuel cell (FC) under different flowrates, temperatures, sampling periods, and membrane-electrode assemblies (MEAs). The results show that Nap, PA, BeP, FL, Pyr, BbC, Ant, and Flu were dominant in anode and cathode emissions of the single PEMFC under different operating conditions. The emission concentrations of Total-PAHs and Total-BaP equivalent carcinogenic potency (BaP eq ) were lower from the anode than from the cathode emission. Moreover, the concentrations of molecular-weight (MW) classified PAHs were in the order low (L) MM-> high (H) MW-> middle (M) MW-PAHs. When the anode/cathode gas flowrates were greater or smaller than 52/35 sccm but at the same sampling volume, the emission concentrations of Total-PAHs and Total-BaP eq increased. The concentration of Total-PAHs decreased but the mass of Total-PAHs increased with the increase of sampling time. However, 64% and 82% of PAH mass were emitted within 12 and 24 h, respectively, based on 36 h sampling at anode/cathode gas flowrates = 52/35 sccm. The concentrations of Total-PAHs or Total-BaP eq of anode or cathode emission were slightly higher at 90°C than at 65°C.The performances of commercial MEAs were in the order SGL < E-TEK < GORE. Nevertheless, the concentrations of anode or cathode emission Total-PAHs or Total-BaP eq for the PEMFC using different MEAs followed the order GORE > E-TEK2 > E-TEK > SGL, while the sums of anode and cathode Total-PAHs emission factors varied with the order SGL > E-TEK > E-TEK2 > GORE (13.3 ± 0.55, 11.5 ± 0.21, 7.91 ± 0.47, and 3.17 ± 0.22 µg g -1 -MEA, respectively). When using the (lab-made) E-TEK2 as the MEA of PEMFC, the PAH profiles of anode and cathode emission gases were similar to those of some carbon materials.
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