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Your Environment. Your Health.

Colorado State University

Superfund Research Program

Chemical Mixtures as Promoters of Hepatocarcinogenesis

Project Leader: Stephen A. Benjamin
Grant Number: P42ES005949
Funding Period: 1995 - 2000

Project Summary (1995-2000)

The long-term goal of this research is to establish whether subchronic exposure to a mixture of chemicals found at hazardous waste sites can act in promotion of carcinogenesis and, if so, what interactions take place in this mixture. A seven chemical mixture, including trichloroethylene, chloroform, benzene, phenol, lead, arsenic and chromium, which models groundwater contamination at Superfund sites, contains known hepatotoxins/ hepatocarcinogens which might be expected to have promoting activity through the induction of cell proliferation. Investigators propose that there is interaction between the individual chemicals and modification of the promoting activity in the mixture and that this activity correlates with cell proliferation. These studies use a rat bioassay employing placental glutathione-S-transferase (GST-P) positive liver cell foci. Oncogene and/or suppressor gene expression or mutation, as they may be affected by the chemical mixture, are also being studied. This information should yield a better understanding of the potential role of environmental chemical mixtures in the carcinogenic process.

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