Environmental chemical detection systems have been subjected to extensive development to give sensitive, specific and in time detection of the potentially hazardous chemical compounds mostly is a highly toxic liquid of vesicant action in addition to other severe physiological symptoms. This paper attempts to outline its detection via gas chromatograph-mass spectrometer combined technique. The fragmentation pattern of the mentioned contaminants in the mass spectrometer by electronic impact is proposed and discussed. The relative abundance of unique ions expected to be formed from the chemical pollutant of interest are given and explained. These ions can be used to program a mobile mass spectrometer for the analysis of the contaminant. The technique is characterized by high sensitivity and can be adapted to monitor the contamination in both vapor and liquid forms.