Effects of adsorption of benzo(a)pyrene onto carbon black particles on levels of DNA adducts in lungs of rats exposed by inhalation

Journal Article · Wed Feb 01 04:00:00 EST 1989 · Toxicol. Appl. Pharmacol.; (United States)

DOI:https://doi.org/10.1016/0041-008X(89)90334-7· OSTI ID:6274920

Wolff, R K; Bond, J A; Sun, J D; Henderson, R F; Harkema, J R; Griffith, W C; Mauderly, J L; McClellan, R O

Exposure of rodents to benzo(a)pyrene (BaP) associated with particles has previously been shown to result in increased retention of BaP and metabolites in lungs. To determine if DNA damage might be enhanced, DNA adducts were measured in lungs of F344 rats following inhalation of pure BaP aerosols or BaP absorbed on carbon black particles. Groups of rats were exposed nose only to filtered air, (14C)BaP (2 mg/m3), or (14C)BaP (2 mg/m3) adsorbed on carbon black (97 mg/m3) (BaP/CB) for 4 hr/day, 1 day/week, for 12 weeks. Groups of rats were terminated at 4, 8, 12, 16, 20, and 24 weeks after the beginning of the 12-week exposure period. Retention of total 14C in lungs was used as an indicator of total reactive metabolites. DNA isolated from lungs was analyzed for adducts using a 32P-postlabeling assay. Inhalation of BaP/CB resulted in 100-fold higher levels of 14C in lungs at the end of the 12-week exposure than did inhalation of pure BaP. The halftime for the decline in 14C levels was 34 +/- 3 weeks (mean +/- SE) for rats exposed to BaP/CB and 6 +/- 2 weeks for rats exposed to pure BaP. At the end of 12 weeks of exposure, DNA adducts in lungs of rats exposed to pure BaP ranged from 2-15 adducts per 10(9) bases (mean = 7, n = 4) and in rats exposed to pure BaP absorbed on carbon black ranged from 10-12 adducts per 10(9) bases (mean = 11, n = 4); DNA adducts in lungs of sham-exposed rats ranged from 0-2 adducts per 10(9) bases (mean = 1, n = 4). The halftimes for the decline in DNA adducts in lungs were 3 +/- 1 weeks (mean +/- SE) for the rats exposed to BaP/CB and 5 +/- 2 weeks for the rats exposed to BaP. One of the DNA adducts found following exposure to both BaP and BaP/CB was tentatively identified as the BaP diol epoxide deoxyguanosine (BPDE) adduct.

• Research Organization: Inhalation Toxicology Research Institute, Albuquerque, NM (USA)
• OSTI ID: 6274920
• Journal Information: Toxicol. Appl. Pharmacol.; (United States), Journal Name: Toxicol. Appl. Pharmacol.; (United States) Vol. 97:2; ISSN TXAPA
• Country of Publication: United States
• Language: English

Related Subjects

550501 -- Metabolism-- Tracer Techniques
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ADDUCTS
ADSORPTION
ANIMALS
AROMATICS
BENZOPYRENE
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOSYNTHESIS
CARBON
CARBON 14 COMPOUNDS
CARBON BLACK
CONDENSED AROMATICS
DAYS LIVING RADIOISOTOPES
DNA ADDUCTS
ELEMENTS
GENETIC EFFECTS
HYDROCARBONS
INHALATION
INTAKE
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LIGHT NUCLEI
MAMMALS
METABOLISM
METABOLITES
NONMETALS
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PARTICLES
PARTICULATES
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
RADIOISOTOPES
RATS
RETENTION
RODENTS
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES
SYNTHESIS
TRACER TECHNIQUES
VERTEBRATES