Supercritical Fluid Extraction of Atrazine and Other Triazine Herbicides from Fortified and Incurred Eggs

Triazines are a class of important pre-emergent weed herbicides. Some members of this class of herbicides exhibit carcinogenic and immunotoxicity properties, which make their use controversial in areas where animal feed crops are grown. It is therefore important to determine if triazine residues are transported to animal food products in order to ascertain the extent of human exposure. Most of the current herbicide residue extraction methods are time-consuming and solvent intensive. Supercritical fluid extraction (SFE) using CO(2) has been used as a alternative for other residue extraction methods as a replacement for hazardous organic solvents. In this study, 10 triazines were extracted from eggs fortified at 100 ppb using unmodified supercritical CO(2) at a pressure of 10000 psi and a temperature of 50 degrees C with off-line collection on a solid phase extraction cartridge containing Florisil. Atrazine recovery averaged 90.4% with an RSD of 3.3%. The other triazines were recovered at mean levels >73%. In a separate feeding study, atrazine and two of its dealkyl metabolites were detected in the egg. The results indicate that SFE is a viable technique for isolating triazine residues from eggs, requiring only 8 mL of solvent for each analysis.