title: Screening of transformation products in soils contaminated with unsymmetrical dimethylhydrazine using headspace SPME and GC-MS.
abstract: The paper describes a novel SPME-based approach for sampling and analysis of transformation products of highly reactive and toxic unsymmetrical dimethylhydrazine (UDMH) which is used as a fuel in many Russian, European, Indian, and Chinese heavy cargo carrier rockets. The effects of several parameters were studied to optimize analyte recovery. It was found that the 85 microm Carboxen/polydimethylsiloxane fiber coating provides the highest selectivity for selected UDMH transformation products. Optimal sampling/sample preparation parameters were determined to be 1-h soil headspace sampling time at 40 degrees C. The GC inlet temperature was optimized to 170 degrees C held for 0.1 min, then 1 degrees C s(-1) ramp to 250 degrees C where it was held for 40 min. Temperature programming resulted in a fast desorption along with minimal chemical transformation in the GC inlet. SPME was very effective extracting UDMH transformation products from soil samples contaminated with rocket fuel. The use of SPME resulted in high sensitivity, speed, small labor consumption due to an automation and simplicity of use. It was shown that water addition to soil leads to a significant decrease of recovery of almost all target transformation products of UDMH. The use of SPME for sampling and sample preparation resulted in detection of the total of 21 new compounds that are relevant to the UDMH transformation in soils. In addition, the number of confirmed transformation products of UDMH increased from 15 to 27. This sampling/sample preparation approach can be recommended for environmental assessment of soil samples from areas affected by space rocket activity.
authors.affiliation: Center of Physicochemical Methods of Research and Analysis, al-Farabi Kazakh National University, 050012 Almaty, 95a Karassai batyr Str., Kazakhstan. bkenesov@gmail.com
authors.forename: Bulat N
authors.initials: BN
authors.lastname: Kenessov
authors.forename: Jacek A
authors.initials: JA
authors.lastname: Koziel
authors.forename: Tim
authors.initials: T
authors.lastname: Grotenhuis
authors.forename: Lars
authors.initials: L
authors.lastname: Carlsen
mesh_terms: D004127:Dimethylhydrazines / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D012989:Soil Pollutants / Q000032:analysis*; D052617:Solid Phase Microextraction / Q000379:methods*; D013696:Temperature
chemical_list: D004127:Dimethylhydrazines; D012989:Soil Pollutants