| Alkylphenols are the stable degradation products of the ionic surfactant alkylphenol ethoxylates. They are toxic, bioaccumulative, persistent and estrogenic therefore recognized as a typical group of environmental endocrine disrupting chemicals. Much concern has been focused on their occurrence and environmental behavior and their ecological risk assessment is of urgent need.I. A sensitive and fast analytical method which can simultaneously determinates 11 phenolic compounds including alkylphenols, chlorophenols and bisphenol A by gas chromatography- mass spectrometry (GC-MS) in environmental samples was established. Using nonpolar dichloromethane as the extraction solvent, the water samples was extracted by liquid-liquid extraction with the spiked recoveries and relative standard deviations were 72.0-94.7% and 2.4-13.4% respectively; the solid phase samples (sediment /sludge) were directly extracted without drying after digested with HCl, and the spiked recoveries and relative standard deviations were 72.0-94.7% and 2.4-13.4% respectively; then the analytes were derivatized with an excess amount of bis(trimethylsilyl)trifluoroacetaminde (BSTFA) and finally the silyl derivetized products were determined by GC-MS. Under the selected chromatographic conditions, the various phenolic target compounds can get baseline separation and the linear correlations were good in the range of 0-3000ng/ml with the aberrance coefficients between 0.9927-0.9998. The detection limits for water and solid phase samples were below 2ng/l and 2ng/g dry weight respectively. The analytical method mentioned above is highly sensitive and selective for phenolic compounds as well as labour-saving and needless of extra expensive equipments, and can realize routine analysis in regular laboratories.Base on the established analytical method, the distribution characteristics and environmental behavior of the target phenolic compounds in various environmental matrices of Jiouzhou Bay and its adjacent rivers,Yangtze River and Yellow River Estuaries were systematically studied for the first time, and the main results are as follows:(1) The spatial distribution characteristics and seasonal variations of phenolic compounds in water,suspended particulates and surface sediments in Jiaozhou Bay and its adjacent rivers were studied. The results show that nonylphenol was the predominant phenolic pollutants in Jiaozhou Bay , with the next important pollutants in the sequence of bisphenol A, octylphenol, butylphenol, and 2,4-dichlorophenol; nonylphenol concentrations in surface water,suspended particulates and surface sediments were 20.2-268.7ng/l,17.1-77.5 ng/l and 3.6-299.3 ng/g dw respectively, and nonylphenol concentrations 90.6-28656ng/l,52.5-27760ng/l和23.8-29723ng/g dw; Moshui River was the most polluted one followed by Haipo River, and the nonylphenol concentrations in rivers were much higher that in Jiaozhou Bay indicating the inflowing rivers were the main source of alkylphenols to Jiaozhou bay;Nonylphenol concentrations in dissolve portion of water and suspended particulates showed similar seasonal variation with higher concentrations in warmer season, and temperature was recognized as the main influence factor; Sediment concentrations of NP in Jiaozhou Bay did not show obvious seasonal variation due to the low sedimentary rate of suspended particulates; Concerning the spatial distribution characteristics, the level of phenolic compounds in the northeast of part of Jiaozhou Bay were much higher than the other parts ,and this distribution pattern was affected by the pollutant sources, circulation system and water exchange conditions together;Nonylphenol concentrations in dissolved portion of water and the suspended particulates were positively correlated and the sediment was the main fate of NP. The contamination level of NP in Jiaozhou Bay and its adjacent rivers was among the highest concentrations of the world;(2) The concentrations of nonylphenol determined in dissolved portion of water, suspended solids and surface sediment in Yangtze River Estuary and its adjacent area ranged between 14.09-173.09 ng/L, 7.35-72.02ng/L and 0.73-11.45 ng/g dw, respectively;The high concentration zone in surface water was located along the direction of Yangtze River freshwater plume with the maximum concentration recorded at the rim of the Maximum Turbidity Zone. The high concentration zone in surface sediment was located in the muddy area to the southeast of Yangtze Estuary and in the coast of Zhejing province, coincided with the direction of suspended solid transportation. Freshwater and suspended solids of Yangtze River were the main sources of nonylphenol in the study area. The distribution pattern of nonylphenol was influenced by hydrodynamic conditions, suspended solid transportation and microbial activity. Compared with other estuarine areas of the world, nonylphenol concentration in surface water of this study is in moderate pollution level.(3)The concentration of nonylphenol in the Yellow River Estuary ranged between 15.7-148.6 ng/l, with the average conctentrations in the surface and bottom water was 45.8 ng/l and 31.0 ng/l respectively; NP was detected in all the sediment samples with the range of 2.3-5.0 ng/g dw;The industry and municipal wastewater carried by Yellow River was the main source of contamination but the produced water from the proximal oil field might be another source too; Seawater dilution and the granularity of the sediment were the dominant factors influencing the distribution of NP in water and the surface sediment respectively; the contamination level of NP was slightly below moderate in water and low in sediment;II. Based on the occurrence study of nonylphenol mentioned above , a primary ecological risk assessment of NP in Jiaozhou Bay, Yangtze River Estuary and Yellow River estuary was attempted by the calculation of risk quotients.(1) The value of RQwater and RQsediment in the water and sediment of Jiaozhou Bay was calculated as 0.12-1.05 and 0.19-7.67 respectively. The risk of NP in sediment was higher than that in water. Harmful biological effects especially endocrine disrupting effects might happen to some invertebrates particularly the benthos. The influence was most seriously in the northeast part of the bay and the NP concentrations had not reached the threshold level of biological effects for fish. The values of RQ in the inflowing rivers were much higher than the PNECwater and PNECsediment of NP except the Baisha River, the biota were seriously threatened by the phenolic compounds, and measures must be taken immediately to mitigate the risk potential. The NP contents in organisms of Jiaozhou Bay were estimated by the BCFs published as 0.08-0.74 mg/kg which were far below the PNECoral(10mg/kg)of NP . Daily ingest of NP through seafood was estimated as 9.20μg/d and 7.04μg/d in winter and summer respectively.(2) The value of RQwater and RQsediment in the water and sediment of Yangtze River Eatuary was calculated as 0.08-0.56和0.02-0.29 respectively whereas the water possessed the higer risk. The sensitive species such as oysters and barnacles may face more potential. Concerns should be paid to the risk potential of NP in the muddy area;(3) The value of RQwater and RQsediment in the water and sediment of Yellow River Eatuary was calculated as 0.05-0.31和0.06-0.13 respectively with the water possessed the higer risk. The sensitive species such as oysters and barnacles may face more potential. The risk potential of NP in the sediment was low. IV.In comparison to the alkylphenols levels in offshore areas, alkylphenols concentrations were investigated in the remote an rural area of Xiling Gorge in Yangtze River where not affected much by sewages.The main pollutants were nonylphenol and bisphenol A with the concentration ranges of 24.2-167.6ng/l and 9.3-99.4ng/l, respectively. The concentrations of nonylphenol at most sampling sites have exceeded the threshold level for undesirable effects to non-target organisms. The organcia pollution status in this area was not optimistic due to the self-purification capacity of the waterbody decreased significantly since the water was impounded by the Three Gorges Project. V.The effluent from sewage treatment plants(STPs) was a main exposure source of nonylphenol in the environment. The removal efficiency of NP and the NP distribution during the process of the wastewater in two STPs in Qingdao employing different techniques were studied as well. The results showed:①The NP concentrations in the influent and effluent of Haipo River STP was 0.94 and 0.25μg/l respectively while the value was 0.12 and 0.29μg/l respectively in Tuandao STP; the concentration of NP in the digested sluge were 84.6 and 2.96μg/g dw in the two STPs respectively;②The transfer and transform of NP during wastewater treatment process was controlled by physical-chemical sorption and microbial biodegradation together, further treatment did not increase the NP removal efficiency obviously; NP accumulated mainly in the anaerobic digestion and the sludge was the fate of NP ;③The removal efficiency of NP was different depending on the treatment processes and the biodegradation of NP was influenced by many factors such as temperature ,hydraulic retention time, diversity of microbes and the initialized concentrations of NP. Which kind of treatment process is more efficient in removing of NP remains further investigation.
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