the testicular effects produced by di(2-ethylhexyl ) phthalate ( dehp ) in the rat , characterized by a decrease in the relative organ weight and histological changes in the seminiferous tubules , can also be produced by di - n - butyl , di - n - pentyl and di - n - hexyl phthalates . 
 the corresponding monoesters of these compounds , formed in vivo as a result of the action of nonspecific esterases in the intestinal mucosa and other tissues , were equally effective in inducing testicular damage . 
 phthalate - induced testicular injury was accompanied by a decrease in the zinc content in the gonads and in increased urinary excretion of this element . 
 exposure of preparations of rat seminiferous tubule cells in culture to monophthalates capable of producing testicular injury resulted in a dose - related detachment of germinal cells from sertoli cells in a manner similar to the effect seen in the intact animal . 
 this in vitro system may find application in the elucidation of the toxic mechanisms involved in phthalate - induced testicular injury and in screening compounds likely to act in a manner similar to phthalates.imagesfigure 1 . 
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