HRGC/HRMS analysis of mirex in soil of Liyang and preliminary assessment of mirex pollution in China.

China is a country with the most severe termite damage in the world. Mirex is one of the two effective orgochlorine pesticides used in China for termite control. A high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) was employed for mirex analysis in soil samples from Liyang city, which once was an important mirex production base in China. The detected mirex levels in soil in Liyang were 2.9-4300pgg(-1)dw (dry weight), with the geometric mean 26.83pgg(-1)dw and the geometric standard deviation 5.02. The highest level occurred at the site near the Liyang Guanghua Chemical Factory. It implies the contribution of industrial activities to the mirex pollution in the surrounding environment. However, the factory only influenced very limited adjacent areas. A Level III fugacity model was developed to study the mirex pollution in Chinese provinces. The results show that the highest concentration occurred in Jiangxi Province, which has the largest consumption of mirex among Chinese provinces. On a regional scale, the calculated concentrations of mirex in the environment are generally so low that it indicates no harm to human and organisms. The total amount of mirex in the environment in China was estimated to be about 25.12tons, most of which exists in soil.