SUPERCRITICAL-FLUID EXTRACTION OF TRIAZINE HERBICIDES FROM SOIL MATRICES

A method of supercritical fluid extraction (SFE) of triazine herbicide s from soil has been developed. The recoveries of triazine herbicides increased with increase in both extraction pressure and temperature wh en supercritical carbon dioxide was used as the extraction medium alon e. Because the recovery by SFE was influenced by the concentration of triazine herbicides in the soil matrix, the addition of methanol to ca rbon dioxide as a polar modifier was required for the satisfactory ext raction of trace levels of the content of the herbicides. The moisture content of the soil also affected the recoveries by SFE. SFE was appl ied to the analysis of real samples. The results by SFE were almost th e same as those from soxhlet extraction.