title: Molecular dosimetry of N2-hydroxymethyl-dG DNA adducts in rats exposed to formaldehyde.
abstract: In this study, both endogenous and exogenous N(2)-hydroxymethyl-dG adducts in nasal DNA of rats exposed to 0.7, 2, 5.8, 9.1, or 15.2 ppm [(13)CD(2)] formaldehyde for 6 h were quantified by a highly sensitive nano-UPLC-MS/MS method. Our data clearly demonstrated that exogenous formaldehyde DNA adducts form in a highly nonlinear fashion, with a 21.7-fold increase in exposure causing a 286-fold increase in exogenous adducts. The ratio of exogenous/endogenous DNA adducts demonstrated that endogenous DNA adducts dominated at low exposures, comprising more than 99%. In contrast, exogenous adducts were not detectable in the bone marrow of rats exposed to 15.2 ppm [(13)CD(2)] formaldehyde.
authors.affiliation: Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina 27599, United States.
authors.forename: Kun
authors.initials: K
authors.lastname: Lu
authors.forename: Benjamin
authors.initials: B
authors.lastname: Moeller
authors.forename: Melanie
authors.initials: M
authors.lastname: Doyle-Eisele
authors.forename: Jacob
authors.initials: J
authors.lastname: McDonald
authors.forename: James A
authors.initials: JA
authors.lastname: Swenberg
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D018736:DNA Adducts / Q000032:analysis* / Q000378:metabolism*; D005557:Formaldehyde / Q000633:toxicity*; D006147:Guanine / Q000031:analogs & derivatives; D009297:Nasal Mucosa / Q000187:drug effects; D051381:Rats; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D018736:DNA Adducts; D005557:Formaldehyde; D006147:Guanine