Pathologic changes induced in respiratory tract mucosa by polycyclic hydrocarbons of differing carcinogenic activity

Journal Article · Wed Nov 01 00:00:00 EST 1978 · Am. J. Pathol.; (United States)

OSTI ID:5830565

Topping, D C; Pal, B C; Martin, D H; Nelson, F R; Nettesheim, P

Seven aromatic polycyclic hydrocarbons (PCHs) were investigated for their toxic effects on respiratory mucosa: benzo(e)pyrene (BeP), pyrene, anthracene, benz(a)anthracene (BaA), dibenz(a,c)anthracene (DBacA), benzo(a)pyrene (BaP), and dimethylbenz(a)anthracene (DMBA). The compounds were chosen because they comprise a spectrum of PCHs ranging from noncarcinogens, to initiators, to weak and strong carcinogens. All of them except DMBA are environmentally relevant chemicals. The chemicals were tested over an 8-week period. Heterotopic tracheal transplants were continuously exposed and the histopathologic effects induced by the various PCHs were periodically assessed semiquantitatively. All PCHs exhibited varying degrees of toxicity for respiratory epithelium and submucosa. BeP clearly showed the least toxicity followed by pyrene and anthracene. BaA and DBacA caused marked epithelial and submucosal changes. In addition to epithelial hyperplasia, undifferentiated epithelium and squamous metaplasia developed. Marked mononuclear infiltration occurred in the subepithelial connective tissue. With BaP the epithelial and submucosal changes were similar but were much stronger. DMBA was the most toxic substance, causing epithelial necrosis followed by generalized keratinizing squamous metaplasia; the subepithelial changes consisted of an early acellular exudate and, later (at 8 weeks), marked condensation and hyalinization of the lamina propria. The toxic response pattern of the tracheal mucosa to carcinogenic agents was characterized by the chronicity of epithelial and connective tissue damage, as opposed to the short-lived hyperplastic and inflammatory response elicited by the noncarcinogens and weak initiators.

• Research Organization: Oak Ridge National Lab., TN
• OSTI ID: 5830565
• Journal Information: Am. J. Pathol.; (United States), Vol. 93:2
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
ANTHRACENE
TOXICITY
BENZANTHRACENE
BENZOPYRENE
PYRENE
RESPIRATORY SYSTEM
ONCOGENIC TRANSFORMATIONS
PATHOLOGICAL CHANGES
POLYCYCLIC AROMATIC HYDROCARBONS
BIOLOGICAL EFFECTS
CARCINOGENESIS
RATS
ANIMALS
AROMATICS
CONDENSED AROMATICS
DISEASES
HYDROCARBONS
MAMMALS
ORGANIC COMPOUNDS
PATHOGENESIS
RODENTS
VERTEBRATES
560305* - Chemicals Metabolism & Toxicology- Vertebrates- (-1987)
550900 - Pathology