台灣地區河川環境水體、底泥及魚體中壬基酚和雙酚A流布及Fugacity model模擬應用

Abstract

Nonylphenol (NP) and Bisphenol A (BPA) are widely used in industrial and household applications. These chemicals may discharge into the environment with industrial and domestic wastewater. Numerous studies have found that NP and BPA widely existed in the environment and biota. Due to NP and BPA are endocrine disruptors able to disrupt reproductive system, it is important to investigate the occurrence of NP and BPA in the environment. The occurrence of toxic substance in the environment can be used to assess exposure risk. Furthermore, it will be as a reference for the management, exposure risk assessment and reduction strategies development of toxic substance. Monitoring of occurrence of toxic substances need lots of manpower and budget, and is difficult to perform due to both temporal and spatial sampling restricts. How to select media which toxic substances will be accumulated to implement the environmental monitoring is the major topic to concern. The fugacity model is one of the multimedia dispersion models and widely used to provide an efficient way to predict the occurrence of contaminants in the environment, and was used as multimedia dispersion models in present study. The objectives of this study are:(1) to investigate the concentrations of nonylphenol and bisphenol A in water, sediment and fishes from principal rivers in Taiwan; (2) to collect and integrate the parameters which is needed for multimedia dispersion simulation and to discuss the integrity and precision,then using fugacity model to predict the concentrations of nonylphenol and bisphenol A in different environmental media of rivers in Taiwan; (3) to estimate organic carbon-water partition coefficient (log Koc), biota-sediment accumulation factor (BSAF) and bioconcentration factor (BCF) using the measured concentrations of nonylphenol and bisphenol A in environmental media. In present study, water, sediment and fish samples in 10 major rivers were sampled in 2012, NP and BPA concentration of those media were measured. The measured NP and BPA concentrations of river water, sediment and fish from twenty one principal rivers in Taiwan during 2009-2011 were collected and integrated to compare with simulative data from fugacity model. The result showed that the mean (range) concentrations of NP in river water, sediment and fish were 1.02 (0.01-10.02) μg/L, 1663.47 (1.98-19624.13) μg/kg dw and 358.79 (11.79-3213.86) μg/kg dw, respectively. The mean (range) concentrations of BPA in river water, sediment and fish were 0.94 (0.01-33.36) μg/L, 26.97 (0.07-471.33) μg/kg dw and 10.58（0.22-145.62）μg/kg dw, respectively. The physical and chemical properties of NP and BPA, environmental parameters of sampling sites and emissions quantities of NP and BPA were collected to simulate the concentrations of NP and BPA in river water and sediment using fugacity model. The simulative concentrations of NP in water and sediment were performed according to four scenarios based on the rationality of release and operation pattern. The mean simulative levels are 7.015, 1.874, 0.200 and 6.257μg/L in water and 1789.007, 545.684, 62.274 and 1400.899μg/kg dw in sediment, respectively. The simulations of BPA concentration in water and sediment were performed according to ten scenarios based on the rationality of release and operation pattern.The mean of simulative levels are 0.276, 0.003, 0.179, 0.002, 0.372, 0.004, 0.370, 0.134, 0.047 and 0.236 μg/L in water and 4.544, 0.039, 1.996, 0.019, 4.152, 0.040, 7.226, 3.215, 1.032 and 3.476 μg/kg dw in sediment, respectively. Comparing the measured and simulative concentrations of NP and BPA, the ratio of measurement and simulation in water are 290 and 1.14, then in sediment are 28 and 2.68 for reasonable scenario which consider specific usage, release ratio and wastewater treatment efficacy. Relatively, the ratio of measured and simulative concentrations in water are 6 and 0.88, and 0.6 and 0.84 in sediment for the scenario only population density of watershed was considered. The results shows that the emission quantities of NP and BPA contributed the great impact to simulative levels, the integrity and precision of emission quantities of NP and BPA should be identified. Finally, the measured concentrations of NP and BPA in the media were used to calculate the log Koc, BSAF and BCF. The log Koc of NP and BPA are varied from 3.42-6.62 and 2.29-4.62, respectively. The BSAF of NP and BPA in different fishes are varied from 0.003-245.598 and 0.003-188.889, respectively. The BCF of NP and BPA in different fishes are varied from 3.18-25991.89 and 1.04-1182.92, respectively. Furthermore, we found log Koc are positively associated with the concentrations of NP and BPA in sediment according to the Spearman correlation analysis. On the other hand, the BSAF of NP and BPA in pelagic fish are negatively associated with log Koc. According to the result, feeding habits in fish may be the important parameter. Compared with pelagic fish, demersal fish live and feed near sediment, the accumulation of NP and BPA in demersal fish may be higher than pelagic fish.