Chromato-mass-spectrometric identification of asymmetric dimethylhydrazine and N-nitrosodimethylamine

Introduction. Environmental safety is one of the main priorities of state policy. It ensures the legal regulation of relations in space activities to strengthen the defense and security of the Russian Federation and further extension of the international cooperation of the Russian Federation. Material and methods. In the fall areas of the stages of the booster rockets, screening studies were carried out to identify the propellant component 1.1-unsymmetrical dimethylhydrazine in atmospheric air (n=14) and drinking water (n=23), determine its metabolite N-nitrosodimethylamine quantitatively in the residents’ blood (n = 90) living in the surveyed areas before the rocket launch (n = 45) and after the launch (n = 45). Also quantitative determination of the N-nitrosodimethylamine metabolite in the residents’ urine in the observation group (n = 108) was performed. For comparison, there was selected a group of residents not related to rocket and space activities (n = 13). Identification and analysis of samples of atmospheric air, drinking water, and biological media (blood, urine) was performed using Agilent 7890A gas chromatograph (USA) with a 5975C quadrupole mass spectrometric detector (MCD) and a capillary column of the HP-FFAP 30m • 0.25mm • 0.25µm series. Results. The study revealed the absence of asymmetric 1.1-dimethylhydrazine in 100% of analyzed atmospheric air samples. During the observation period, the concentrations of N-nitrosodimethylamine in the range of 0.00039 to 0.001 mg/dm3 were found in drinking water samples that did not exceed the hygienic standard (LOCNDMA 0.01 mg/dm3). N-nitrosodimethylamine in a concentration range of 0.00095-0.346 mg/dm3 was determined in the blood samples of the population. The studies revealed that after the rocket launch, the N-NDMA concentration in the blood was 1.8 times higher than the concentration registered before the rocket launch. In the urine sample of the resident living in the surveyed area, N-nitrosodimethylamine was detected with a high degree of reliability according to the essential ion with mass 74 m/z and confirmatory ion of 42 m/z, and the concentration was quantitatively calculated at a level of C N-DMA = 0.23 μg/ml. The detection of N-nitrosodimethylamine in blood and urine, even in trace amounts, indicates the possibility of exposure. Conclusion. Performed comprehensive studies made it possible to prove the relative safety of the ecological situation in the fall areas of the booster rockets that are located close to settlements when considering the environmental pollution with unsymmetrical dimethylhydrazine and can be used for systematic monitoring.