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Water solubility enhancements by two types of dissolved organic matter (DOM) extracted from a local wastewater treatment plant and by a commercial humic acid (HA) have been studied for tetrabromobisphenol A (TBBPA) using batch equilibrium technique, and the characteristics of DOM were studied with the aid of infrared and ultraviolet absorbance, elemental analysis, dialysis membranes and scanning electron microscope (SEM). The results showed that the effectiveness of DOM in enhancing solute solubility appeared to be controlled by the structure and molecular size of DOM, the ionic strength of solution and the dissociation ratio of TBBPA. Langmuir Equation could fit the isotherms of the total influent DOM and effluent DOM, and their binding coefficients (Kdoc) are 1.19 x 10(5) L x kg(-1) and 1.27 x 10(5) L x kg(-1), respectively. The interaction of TBBPA with DOM (relative molecular weight > 1000) can be explained by partition according to the linear isotherms, while the nonideal binding behavior of the total DOM was caused by DOM (relative molecular weight < 1000) which contributed about 75 % to 80% of the total water solubility enhancement effect and had higher binding coefficients to TBBPA, about 55%, than those of DOM (relative molecular weight > 1000). The capability of solubility enhancements by the influent DOM and effluent DOM was greater than that of HA in which the high molecular weight DOM controlled the effect of solubility enhancement. In addition, it was also found that the capability of solubility enhancements was affected by the ionic strength of solutions. The capability of solubility enhancements was increased when the ionic strength was low, while it was decreased at higher ionic strength due to the aggregation and flocculation of DOM.

Sorption and desorption behaviors of tetrabromobisphenol A (TBBPA) on fluvo-aquic soil were investigated using batch equilibrium experiments, and the effects of pH and ionic strength on the sorption were also evaluated. The results showed that the sorption process could be divided into the rapid sorption (0-24 h) and the slow sorption (24-48 h). The rapid sorption played the main role in the sorption of TBBPA and the sorption approached equilibrium at about 48 h. The nonlinear isotherm of TBBPA on the soil was observed, and the sorption behavior could be described by Freundlich model well. The amount of TBBPA sorption decreased with the increase in solution pH within the range of pH 6.0-8.0, and did not change significantly with the increase in solution pH when pH value was greater than 8.0. The amount of TBBPA sorption increased with the increase in ionic strength. In addition, the result of sorption-desorption revealed that desorption hysteresis of TBBPA, which suggested that the fluvo-aquic soil had high affinity with TBBPA.

Acute toxicity of BPA and TBBPA to Daphnia magna, zebrafish (Brachydanio rerio) and development effects of zebrafish embryo and zebrafish. The tested chemicals remarkably restrained the were studied, and safety assessment was also made to Daphnia magna mobilization of Daphnia magna, which may cause them death. 48 h EC50 values for D. magna were 8.91 and 0.69 mg x L(-1) respectively. In addition, the chemicals showed the toxicity effects on zebrafish, and 96 h LC50 values were 9.06 and 1.78 mg x L(-1) respectively. BPA and TBBPA remarkably retarded the development of zebrafish embryos, which may cause embryo abnormality and death. And the most sensitive toxicological endpoints to BPA and TBBPA were found, 72 h EC50 (malformation and embryo do not hatch) values were 2.90 and 0.14 mg x L(-1) respectively. The results showed that zebrafish embryo should be the most sensitive to the tested chemicals. The results indicated that BPA and TBBPA were the pollutants with high toxicity, in which TBBPA had the higher toxicity. BPA is a potential teratogen to zebrafish embryos, while TBBPA restrains embryo from hatch.

The aim of this study is to build a method of determining PBDEs in biota, and to gain the optimum condition of preparation of samples, and the best condition of Gas Chromatography (GC) and Mass Spectrometer (MS). Also, the requirements of quality, quantity and experimental condition were assessed. According to the validation of the quality control (QC), the results proved that the analytical method satisfied the requirements of the determination of PBDEs in biota. The recoveries were between 50.5% and 112.3%, of which the relative standard deviations were between 5.3% and 9.9% , and the limits of detection were between 7.1 and 161.8 pg/g. Based on the determination method, several bred and wild fishes were analyzed. The concentration of PBDEs in the wild Chinese perch and crucian carp and 2 bred weevers were 1.53, 1.11, 5.31, 6.15 ng/g(dry weight), respectively, and the most congener was BDE47.