Assessment of the estrogenic effects of zearalenone after treatment with ozone utilizing the mouse uterine weight bioassay

The ability of ozone gas (O3) to detoxify zearalenone (ZEN), a commonly occurring estrogenic mycotoxin, was assessed utilizing the mouse uterine weight bioassay. Solutions containing 12 ppm ZEN in water were ozonated for varying time periods (0, 0.5, and 5 min), then extracted with chloroform and evaporated to dryness. The residue was redissolved in acetonitrile and analyzed for ZEN. High-performance liquid chromatography (HPLC) analysis of aliquots indicated a rapid degradation and decline in parent ZEN level with increasing time of ozone treatment. The acetonitrile solution containing the degraded ZEN residue was added to a known volume of corn oil and evapo rated under nitrogen to eliminate the acetonitrile in the oil. Eighteen-day-old prepubertal female mice (B6C3F1 strain) were gavaged daily with the test chemicals in 50 mul of corn oil between d 18 and 23. Initial dose-response studies showed that a concentration of 60 mug ZEN/mouse/d produced uterine weights that were significantly higher than the ...