Abstract: Ultrasonic extraction was used in the study on the analysis of 1,2,4-trichlorobenzene. In the study, 1,2,4-TCB in water samples was extracted with n-hexane whereas that in soil and plant, with mixture of n-hexanc and acetone at 9: 1. In all experiment, extractant of 15-25ml and an extraction time of 2h were performed. The recoveries of 1,2,4-trichlorobenzene from water, soil and plant (tissue stem and foliage of alfalfa and rice grain) were found to be more than 85%, 65% and 62%, respectively. The method was simple, sensitive and reliable for the analysis of 1,2,4-TCB, which is a volatile chemical, with low reagent demand, and applicable in the analysis of other chlorobenzenes in environment.

Key words: Tongling, phytoplankton, community structure, heavy metal.