| In this study, on the basis of reviewing the pretreated method and separation instrument method of the trace odorous compounds such as 2-methylisobomeol (2-MIB) and trans-1,10-dimethyl-trans-9-decalol (Geosmin) and the trace antibiotic residues in the source of drinking water, a rapid, accurate and high-efficiency method for determination of odorous compounds such as 2-methylisobomeol (2-MIB) and trans-1,10-dimethyl-trans-9-decalol (Geosmin) in the source of drinking water was developed by solid-phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) and determination of antibiotic residues in the source of drinking water was developed by solid-phase extraction (SPE) followed by rapid separation liquid chromatography-tandem mass spectrometry (RSLC-MS2). The established analysis methods were successfully applied to the most representative source of drinking water such as the raw water of Yuqing waterworks and Quehua waterworks in Jinan. For the first time, the seasonal variation of the trace organic compounds’ concentration in the source of drinking water in Jinan was obtained and the removal efficiency of the trace organic compounds in the source of drinking water was discussed using the established method. This dissertation included the following contents and conclusions:(1)Study on analysis method of the trace odorous compounds such as 2-MIB and GSM by SPME-GC/MS in the source of drinking waterSPME was selected to extract the two odorous compounds such as 2-MIB and GSM in the source of drinking water. The optimized conditions of SPME was followed:DVB/CAR/PDMS fiber was found to possess the best extraction efficiency for the odorous compounds in water. SPME was carried out by using 25mL samples, addition of 6g NaCl, stirring at 1150 rpm and temperature at 80℃for 15 min to enrich the target analytes. After that, the fiber was desorbed at 250℃for 2min and determined by GC-MS. The column temperature was held at 80℃for 2 min, increased to 165℃at 15℃/min, then increased to 170℃at 2℃/min with a 5min hold. For selected ion monitoring (SIM) mode, six qualitative ions were monitored (m/z 95,107,108 for 2-MIB; m/z 111,112,125 for GSM) and two quantitative ions were monitored (m/z 95, for 2-MIB; m/z 112, for GSM). The quality control and the quality assurance showed that the opt-imized method has been proved with excellent linearity and precision. Using this method, the calibration curves of 2-MIB and GSM were linear in the range of 10～500 ng/L, and the correl-ation coefficients were both above 0.999. The average recovery rates of 2-MIB and GSM in samples were 99.43% and 97.37%, and the RSD were in range of 1.6%～5.9%. The detection limits (S/N=3) of 2-MIB and GSM were 1.2 and 0.9 ng/L, respectively. The optimized SPME-GC/MS was proved to be a rapid, accurate and sensitive method for determination of the trace odorous compounds such as 2-MIB and GSM in the source of drinking water and applied with satisfactory results.(2) Study on analysis method of the trace antibiotic residues by SPE-RSLC/MS2 in the source of drinking waterSPE was selected to extract the six antibiotic residues in the source of drinking water. The optimized conditions of SPE was followed:Oasis HLB (200 mg/6cc) extraction cartridge was found to possess the best extraction efficiency for antibiotic residues in water. SPE was carried out by using 500mL samples, addition of 500μL Na2EDTA solution with the concentration of 2μg/mL and pH was adjusted to 2.8. The samples were loaded onto the cartridge at a flow rate of 8mL/min. After that, the cartridge must be dry thoroughly and rinsed with 9mL methanol to a 10mL centrifugal tube with cork. Using rapid separation liquid-triple LC/MS2, the optimized separation instrument conditions were listed as followed:The gradient elution program used was: from 85% to80% A(for 5min) in 1min, then to 75% A in 1min, to 20%A(for 3min) in 3min, return to 85%A in 5min and the six antibiotic residues were separated within 18 min. Data acquisition for quantification and confirmation was performed in the multiple reaction monitoring (MRM) mode. The quality control and the quality assurance showed that the optimized method has been proved with excellent linearity and precision. Using this method, the calibration curves of the six antibiotic residues were linear in the range of 5～4000 ng/L, and the correlation coefficients were in the range of 0.9922～0.9999. The average recovery rates of them in samples were in range of 85.1%～106.2%, and the RSD were in range of 1.6%～11.5%. The detection limits (S/N=3) were in range of 0.8～3.2ng/L. The optimized analysis method was proved to be a very practical method for detennination of the six antibiotic residues in the source of drinking water and applied with satisfactory results.(3) The analysis methods for determing the trace organic compounds in the source of drink-ing water were applied to study on the distribution variation and the treatment process.The most representative source of drinking water such as the raw water of Yuqing waterworks and Quehua waterworks in Jinan were determined by the established method. April 2011 to March 2012 was selected as a survey period. The results showed that there was obviously seasonal variation of the trace organic compounds’concentration in the source of drinking water in Jinan. The concentration of the trace odorous compounds such as 2-MIB and GSM would reach the peak value in August and September of every year because of the exuberant algae propagation. To the contrary, the concentration of the trace the six antibiotic residues was higher relatively in the season of less rainfall and frequent illnesses, especially the spring and the winter. Compared to Quehua waterworks, the concentration of the trace odorous compounds in the raw water of Yuqing waterworks was lower, but the antibiotics’was higher because of the differences of the dominant species and the sewage discharge in the Quehua reservoir and the Yuqinghu reservoir. The samples collected from April 2011 to March 2012 in the water treatment system of Yuqing waterworks and Quehua waterworks were determined by the established method. The results showed that the removal efficiency of the trace organic compounds using the common technologies was unsatisfactory. With the increase of the depth treatment technology such as ozone-activated carbon the removal efficiency of the odorous compounds increased to more than 90% and the six antibiotics increased to more than 70%. The application showed that the established method in this study applied with satisfactory results for the routine monitoring and the research work. |
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