Jansen EHJMvan den Ham WAde Fluiter Pvan Leeuwen FXR2014-01-171993-06-30In a study in which male rats have been exposed to 0, 200, 600, 2000, 6000 and 20000 mg diethylphthalate (DEP)/kg diet for 2 weeks, body weight and liver weight and a number of enzyme parameters which are related with peroxisome proliferation (palmitoyl coenzyme-A oxidase (PCO), enoyl coenzyme-A hydratase (ECH), carnitine acetyl transferase (CAT) and lauric acid hydroxylase (LAH) have been determined in liver homogenates. No effects have been observed on the liver and body weights. PCO and LAH showed no effects up to 2000 and 600 mg DEP/kg diet, respectively. ECH was more sensitive with a dose-without-effect (DWE) of 200 mg/kg diet. Cat was the most sensitive parameter with an effect in all dose groups. Although CAT turned out the most sensitive parameter, this enzyme was not considered in the establishment of an overall no-observed-effect-level for peroxisome proliferation since it is not specific for peroxisome proliferation. The second most sensitive parameter was the ECH activity. Therefore an overall no-observed-effect-level for peroxisome proliferation of 200 mg DEP/kg diet was established corresponding to 19 mg DEP/kg b.w./day.<br>34 pen07ftalatendiethylftalaattoxiciteitstestendierproevenenzymenphthalatesdiethyl phthalatestoxicity testingnelanimal modelsenzymesdepperoxisome proliferationpalmitoyl coenzyme-a oxidasepcoenoyl coenzyme-a hydrataseechcarnitine acetyl transferasecatlauric acid hydroxylaselahliver homogenatesReport2014-01-17