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.

Quantification and kinetic study in plasma and tissues of (E)-1,1,4,4-tetramethyl-2-tetrazene, a liquid propellant and a transformation product of 1,1-dimethyl hydrazine

“…For TMTZ, the limit of quantification in the water sample was 9 and 90 ng/mL using an amperometric and spectrophotometric detector, respectively [8]. Another study based on headspace SPME-GC-MS apparatus was developed for the screening of transformation products from soil and water samples [7,11]. The present assay is the first one describing the quantification of TMTZ in biological media.…”

Determination of 1-methyl-1H-1,2,4-triazole in soils contaminated by rocket fuel using solid-phase microextraction, isotope dilution and gas chromatography–mass spectrometry

“…1). Increase of water content in soil leads to the decrease of peak areas of UDMH transformation products, due to their high polarity and affinity to water [15]. Other important parameters affecting SPME effectiveness are mechanical composition [21] and organic carbon content [20,22].…”

“…Recently a new method based on headspace solid-phase microextraction (SPME) and GC-MS was developed for screening of UDMH transformation products in soil samples [15]. The method is based on extraction of analytes by a thin polymer coating from headspace of soil or soil-water mixture in a closed vial followed by thermal desorption in a heated GC injection port (Fig.…”

“…Addition of excess water leads to the increase of detection limits for polar analytes [15,31] and inaccurate results due to formation of complexes [20]. Pre-SPME extraction by organic solvent and cold fiber SPME significantly increase complexity of analysis and lead to additional expenses.…”

“…GC-MS Screening, n/a [15] MTA Injection of 10 mL of MTA-d3 (24 mg L À 1 ). Equilibration during 5 h at 80°С, headspace SPME by 85 μm Car/PDMS, extraction time 1 min, temperature 80°С…”