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Your Environment. Your Health.

Project Publications: Colorado State University: Chemical Mixtures as Promoters of Hepatocarcinogenesis

Superfund Research Program

Chemical Mixtures as Promoters of Hepatocarcinogenesis

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



  • Dean, Jr. CE, Benjamin SA, Chubb LS, Tessari JD, Keefe TJ. 2002. Nonadditive hepatic tumor promoting effects by a mixture of two structurally different polychlorinated biphenyls in female rat livers. Toxicol Sci 66(1):54-61. PMID:11861972


  • Pott WA, Benjamin SA, Yang RH. 2001. Pharmacokinetics, metabolism, and carcinogenicity of arsenic. Rev Environ Contam Toxicol 169:165-214. PMID:11330077


  • Gustafson DL, Long ME, Thomas RS, Benjamin SA, Yang RH. 2000. Comparative hepatocarcinogenicity of hexachlorobenzene, pentachlorobenzene, 1,2,4,5-tetrachlorobenzene, and 1,4-dichlorobenzene: application of a medium-term liver focus bioassay and molecular and cellular indices. Toxicol Sci 53(2):245-252. PMID:10696772
  • Thomas RS, Conolly RB, Gustafson DL, Long ME, Benjamin SA, Yang RH. 2000. A physiologically based pharmacodynamic analysis of hepatic foci within a medium-term liver bioassay using pentachlorobenzene as a promoter and diethylnitrosamine as an initiator. Toxicol Appl Pharmacol 166(2):128-137. PMID:10896854


  • Benjamin SA, Yang RH, Tessari JD, Chubb LS, Brown MD, Dean CE, Keefe TJ. 1999. Lack of promotional effects of groundwater contaminant mixtures on the induction of preneoplastic foci in rat liver. Toxicology 137(3):137-149. PMID:10522494


  • Pott WA, Benjamin SA, Yang RH. 1998. Antagonistic interactions of arsenic-containing mixtures in a multiple organ carcinogenicity bioassay. Cancer Lett 133(2):185-190. PMID:10072168
  • Thomas RS, Gustafson DL, Pott WA, Long ME, Benjamin SA, Yang RH. 1998. Evidence for hepatocarcinogenic activity of pentachlorobenzene with intralobular variation in foci incidence. Carcinogenesis 19(10):1855-1862. PMID:9806169
  • Thomas RS, Gustafson DL, Ramsdell HS, El-Masri HA, Benjamin SA, Yang RH. 1998. Enhanced regional expression of glutathioneS-transferase P1-1 with colocalized AP-1 and CYP 1A2 induction in chlorobenzene-induced porphyria. Toxicol Appl Pharmacol 150(1):22-31. PMID:9630449
  • Yang RH, Thomas RS, Gustafson DL, Campain JA, Benjamin SA, Verhaar HJ, Mumtaz MM. 1998. Approaches to developing alternative and predictive toxicology based on PBPK/PD and QSAR modeling. Environ Health Perspect 106(suppl.6):1385-1393. PMID:9860897


  • Benjamin SA, Chubb LS, Dean, Jr. CE, Tessari JD, Yang RH, Brown MD. 1997. Lack of preneoplastic foci in rats exposed to a hazardous waste groundwater mixture in a medium-term hepatic initiation/promotion assay. Environ Health Perspect 36:153.


  • Constan AA, Benjamin SA, Chubb LS, Tessari JD, Baker DC, Yang RH. 1996. Concurrent apoptosis and hepatocellular proliferation prevent increased formation of enzyme-altered foci in F344 rats exposed to a mixture of groundwater contaminants. Environ Health Perspect 30:160.
  • Constan AA, Benjamin SA, Tessari JD, Baker DC, Yang RH. 1996. Increased rate of apoptosis correlates with hepatocellular proliferation in Fischer-344 rats following long-term exposure to a mixture of groundwater contaminants. Toxicol Pathol 24(3):315-322. doi:10.1177/019262339602400307 PMID:8736387
  • Dean, Jr. CE, Benjamin SA, Yang RH, Chubb LS, Tessari JD. 1996. Cell proliferation, apoptosis, and promotion of preneoplastic foci in rat liver after exposure to a model hazardous waste groundwater mixture. In: Proceedings of the FASEB (Federation of American Societies for Experimental Biology) Summer Research Conference: Cellular and Molecular Mechanisms for Liver Growth Regulation. Snowmass, CO.
  • Thomas RS, Chubb LS, Constan AA, Benjamin SA, El-Masri HA, Veeramachaneni D, Tessari JD, Nett TM, Palmer J, Miller C, Kinonen C, Arguello J, Cosma G. 1996. Male reproductive toxicity following perinatal exposures to the anti-androgen p,p-DDT. In: Proceedings of the 35thAnnual Meeting of the Society of Toxicology Meeting, March 10-14, 1996. Anaheim, CA.


  • Benjamin SA, Constan AA, Yang RH, Tessari JD, Baker DC. 1995. Lack of correlation between liver cell proliferation and preneoplastic foci in rats exposed to a mixture of groundwater contaminants. Toxicol Pathol 23:756.
  • Constan AA, Yang RH, Baker DC, Benjamin SA. 1995. A unique pattern of hepatocyte proliferation in F344 rats following long-term exposures to low-levels of a chemical mixture of groundwater contaminants. Carcinogenesis 16(2):303-310. PMID:7859362
  • El-Masri HA, Thomas RS, Benjamin SA, Yang RH. 1995. Physiologically based pharmacokinetic/pharmacodynamic modeling of chemical mixtures and possible applications in risk assessment. Toxicology 105(2-3):275-282. PMID:8571364
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