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ObjectiveTo establish a GC-MS method for the detection of 9 halogenated alkanes in toothpastes. MethodsVarious brands of toothpastes on the market were collected as the samples. Methanol was used as the extraction solution. After shaking， vortex and centrifugation， the supernatant was filtered by 0.45 μm microporous filter membrane. The content of 9 halogenated alkanes including chloromethane， dichloromethane， chloroform， 1，1，1-trichloroethane， carbon tetrachloride， 1，2-dichloroethane， 1，1，2-trichloroethane， 1，2-dibromoethane， 1，2，3-trichloropropane in the filtrate were determined by GC-MS. ResultsThe 9 halogenated alkanes showed a good linear relationship in the concentration range of 0.03‒1.00 μg·mL-1. The correlation coefficient was ≥0.998 7 with the detection limits of 0.015‒0.056 mg·kg-1. The spiked recoveries were 83.2%‒108.9% with the RSD of 2.0%‒9.8%. In the actual sample analysis， 1，1，2-trichloroethane and 1，2，3-trichloropropane were respectively detected in 6 toothpaste samples from 5 brands. ConclusionThe method is simple， sensitive， accurate， and has good spiked recoveries. It can be used for the determination of halogenated alkanes in toothpastes.
RESUMO
Objective To establish a method to determine halogenated alkane hydrocarbon in drinking water with headspace gas chromatography. Methods Halogenated alkane hydrocarbon in the water were extracted by headspace technology, then analyzed with DB-5 capillary column, in the same time, they were determined with GC by controlling the temperature and the speed of nitrogen. The retention time of the peaks was used for qualitative analysis, while external standard method was used for quantitative analysis. Results The linear ranges for dichloromethane, trichloromethane, 1, 1, 1-trichloroethane, 1, 2-dichloroethane, carbon tetrachloride, trichloroethylene, bromodichloromomethane, 1, 1, 2-trichloroethane, dibromochloromethane, tetrachloroethylene, tribromomethane were 0.8-4 024.0, 0.007-33.5, 0.004-19.2, 1.4-6 821.0, 0.002-10.0, 0.005-25.6, 0.002-12.1, 0.1-717.8, 0.005-23.5, 0.002-8.1 and 0.02-87.7 ?g/L. The lowest determination limit were 0.01- 4.1 ?g/L, the rate of recovery were 89.7%-110.0% and RSDs were 2.8%-9.0%. Conclusion This method can efficiently separate and accurately determine 11 kinds of halogenated alkane hydrocarbon in drinking water. It is simple, rapid and sensitive.
RESUMO
Objective To establish a test method of dichloromethane,1,1-dichloroethylene,1,2-dichloroethylene,1,2-dichloroethane in drinking water with headspace gas chromatography.Methods Halogenated alkane hydrocarbon in the water was extracted by headspace technique,then analyzed with DB-624 capillary column.In the same time,determined with GC by controlling the temperature.Retention time of the peaks was used for qualitative analysis,while external standard method was used for quantitative analysis.Results The linear ranges for dichloromethane,1,1-dichloroethylene,1,2-dichloroethylene,trans-1,2-dichloroethylene,1,2-dichloroethane were 0.85-168,0.07-12.1,0.40-77.8,0.53-119 and 1.2-265 ?g/L respectively,the determination limits were 0.83,0.07,0.40,0.53 and 1.10?g/L respectively,r≥0.999 5,the rate of recovery were 102.5%-113.8%,and RSDs were 5.5%-11.8%.Conclusion This method is simple,rapid and sensitive,can efficiently separate and accurately determine 5 kinds of halogenated alkane hydrocarbon in the water and only takes 5.2 minutes.
RESUMO
Objective To develop a method of determining benzene hydrocarbon and halogenated alkane hydrocarbon in the air of workplaces with the capillary gas chromatography of carbon disulphide desorption. Methods Benzene hydrocarbon and halogenated alkane hydrocarbon in the air of workplace were collected by active carbon sampling cuvette, then separated by hydrogen flames detector gas chromatography machine after carbon disulphide desorption. Benzene hydrocarbon and halogenated alkane hydrocarbon were determined quantitively by retention time and quantitatively by apex area. Results The linear ranges of benzene, toluene, p-xylene, m-xylene, o-xylene, ethyl benzene, styenl, chlorobenzene, acetone, carbontetrachloride, dichloromethanl, trichloromethane, 1, 2-dichloroethane, naphth alene were 0.019-81.600, 0.018-91.200, 0.018-88.800, 0.018-56.8, 0.011-92.000, 0.012-63.200, 0.018-93.200, 0.449-2298.400, 0.252-1287.000 and 0.076-390.000 mg/m3 respectively. The recovery rates were 88.4%-98.6% and RSD were 1.0%-6.0%. Conclusion This method can separate efficiently and determine accurately benzene hydrocarbon and halogenated alkane hydrocarbon in the air with a good precision. It is suitable for the determination of the toxicants in the air.