Influence of airborne particulates on respiratory tract deposition of inhaled toluene and naphthalene in the rat.
Inhal Toxicol
; 30(1): 19-28, 2018 01.
Article
em En
| MEDLINE
| ID: mdl-29465005
ABSTRACT
OBJECTIVE:
Most studies report that inhaled volatile and semivolatile organic compounds (VOCs/SVOCs) tend to deposit in the upper respiratory tract, while ultrafine (or near ultrafine) particulate matter (PM) (â¼100 nm) reaches the lower airways. The objective of this study was to determine whether carbon particle co-exposure carries VOCs/SVOCs deeper into the lungs where they are deposited. MATERIALS ANDMETHODS:
Male Sprague-Dawley rats were exposed by inhalation (nose-only) to radiolabeled toluene (20 ppm) or naphthalene (20 ppm) on a single occasion for 1 h, with or without concurrent carbon particle exposure (â¼5 mg/m3). The distribution of radiolabel deposited within the respiratory tract of each animal was determined after sacrifice. The extent of adsorption of toluene and naphthalene to airborne carbon particles under the exposure conditions of the study was also assessed.RESULTS:
We found that in the absence of particles, the highest deposition of both naphthalene and toluene was observed in the upper respiratory tract. Co-exposure with carbon particles tended to increase naphthalene deposition slightly throughout the respiratory tract, whereas slight decreases in toluene deposition were observed. Few differences were statistically significant. Naphthalene showed greater adsorption to the particles compared to toluene, but overall the particle-adsorbed concentration of each of these compounds was a small fraction of the total inspired concentration.CONCLUSIONS:
These studies imply that at the concentrations used for the exposures in this study, inhaled carbon particles do not substantially alter the deposition of naphthalene and toluene within the respiratory tract.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sistema Respiratório
/
Tolueno
/
Poluentes Atmosféricos
/
Material Particulado
/
Naftalenos
Limite:
Animals
Idioma:
En
Revista:
Inhal Toxicol
Assunto da revista:
TOXICOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Estados Unidos