title: The role of regenerative cell proliferation in chloroform-induced cancer.
abstract: Chloroform produces cancer by a nongenotoxic-cytotoxic mode of action, with no increased cancer risk expected at noncytotoxic doses. The default risk assessment for inhaled chloroform relies on liver tumor incidence from a gavage study with female B6C3F1 mice and estimates a virtually safe dose (VSD) at an airborne concentration of 0.000008 ppm of chloroform. In contrast, a 1000-fold safety factor applied to the NOAEL for liver cytotoxicity from inhalation studies yields a VSD of 0.01 ppm. This estimate relies on inhalation data and is more consistent with the mode of action of chloroform.
authors.affiliation: Chemical Industry Institute of Toxicology, Research Triangle Park, NC 27709, USA.
authors.forename: B E
authors.initials: BE
authors.lastname: Butterworth
authors.forename: M V
authors.initials: MV
authors.lastname: Templin
authors.forename: S J
authors.initials: SJ
authors.lastname: Borghoff
authors.forename: R B
authors.initials: RB
authors.lastname: Conolly
authors.forename: G L
authors.initials: GL
authors.lastname: Kedderis
authors.forename: D C
authors.initials: DC
authors.lastname: Wolf
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects*; D002725:Chloroform / Q000633:toxicity*; D004247:DNA / Q000187:drug effects; D005260:Female; D006801:Humans; D051379:Mice; D009369:Neoplasms / Q000139:chemically induced*; D051381:Rats; D018570:Risk Assessment
chemical_list: D002725:Chloroform; D004247:DNA