The Research On Detection Method Of Toxaphene Residue In Soil And Water

As one of the most important group of Persistent Organic Pollutants (POPs), Toxaphene, with intense toxicity, high residuary, hardness of being metabolized, easier to be enriched by biology and with long-range transportability, so that ,it have stirred interest in the study of Environment Science. Up to now, Toxaphene has become main object in environment investigation. The complexity of the toxaphene mixture has intrigued and challenged analytical chemists for decades, and it is still difficult to quantitative analysis. The present thesis studied systematism the process of detection toxaphene, and covered toxaphene extraction, cleanup and detection technique. Moreover, the method of toxaphene analysis in soil by ASE - NCI/ MS, and analysis the object in water by solid-phase disk extraction (SPE) - NCI/MS were developed. These methods are convenient, fast, environmental protection, high sensitivity, accuracy, good relative standard deviation and content with Green Analytical Chemistry's requirement.Comparative study of using GC-NCI/MS, GC-EI/MS, GC-ECD to detecting toxaphene was conducted, the GC-NCI/MS technique has few applications in china. The equipment detection limit was 0.1ng/mL,5ng/mL,0.4ng/mL. The accurate qualitative and quantitative of tocxaphene can't be achieved by GC-ECD,the GC-EI/MS can't detect trace samples, but GC-NCI/MS method not only has a very low detection limit, but also have a very strong qualitative capacity, which is showed to be the best detection method.The co-cleanup techniques of solid phase extraction with florisil column, silica gel column, alunima column and Cleanert PestiCarb which were used to eliminate the recoveries of toxaphene. The average recoveries of the co-cleanup technique by Cleanert PestiCarb and Florisil column was the best, the recoveries of toxaphene was ranged from 87.5% to 97.9%, the relative standard deviation was in range of 5.05% to 12.25%.The ASE and MAE were modern pre-treatment technology of solid sample. The power, solvent, pressure, temperature, and times were optimized. The average recoveries of two optimized mothods were 102.5% and 95.2%, they were significantly higher than 79.6% of the SE method. Two methods can be used in soil sample's extraction, MAE can deal with twenty-four samples at the same time, but it need more solvent, more steps and not safe than ASE. In the optimized conditions of ASE, the average recovery was 92.2%- 105.6%, the MRL were 0.1-3.0ng/g,the precision is 2.97%-12.35% (n=7),so it was suitable to be used in laboratory.Three methods of liquid - liquid extraction (LLE), solid-phase column extraction (SPE column) and solid-phase disk extraction (SPE disk) were used in pre-treatment of water samples. In SPE methods we selected Empore^TM-C18 DISK membrane and GDX-502 resin which made in china was used to the enrichment of phenolic compound. Some factors influencing the extraction efficiency of SPE method, such as pH value of water sample, extraction pressure and elution solution were studied. The result indicated that the average recovery of the LLE, the column SPE and the disk SPE were 66.7%-86.7%,78.4%-95.3% and 90.5%-103.1%, respectively, but the efficiency of the disk SPE was three times than the column SPE. The MRL of the SPE disk was 0.5-30ng/L, the precision is 3.64%-10.16% (n=7). This SPE disk method has fast flow, high, absorbability, lower counter pressure, so it has been used more widely in domestic and abroad these years.Finally, the established pretreatment and detection method were applied successfully to soil and water samples obtained from different regions for the determination of toxaphene residue. The results showed that most of samples had been polluted in different levels. The method has been proved to be credible.