Jute batching oil: a tumor promoter on mouse skin

A mineral oil essentially used in the jute industry for the "batching" of jute fibers, and earlier reported to be nontumorigenic on mouse skin, has been found to be a tumor promoter following a two-stage mouse-skin bioassay protocol. The types of tumors developed after initiation with a single dose of urethane or 3-methylcholanthrene (subcutaneously), followed by repeated skin painting with jute batching oil (JBO) included benign papillomas, keratoacanthomas, and fibrosarcomas. Chemical analysis of this oil indicated the total aromatic content was 11.71% and the amount of fluoranthene, pyrene, chrysene, and triphenylene was in the range of 192.54 to 227.79 mg/kg in the test sample. The underlying biochemical mechanisms for the tumor-promoting effect of JBO seemed to operate through a different pathway rather than involving the induction of cytochrome-dependent monoxygenase and N-demethylase activities in the tissue.