Biomaterial Database

Particle inhalability curves for humans and small laboratory animals. 1995

M G Ménache, and F J Miller, and O G Raabe

Center for Extrapolation Modeling, Duke University Medical Center, Durham, NC 27710, USA.

Several inhalability curves for nose breathing in humans have been developed. No studies have been designed specifically to develop inhalability functions for animals, although it has been shown that pulmonary deposition of large particles (> 4-5 microns) via inhalation is minimal in laboratory animals [Raabe et al., Inhaled Particles VI, pp. 53-63. Pergamon Press, Oxford (1988)]. The logistic function was fitted to these animal deposition data of Raabe et al. (1988) to estimate an inhalability curve for laboratory animals. The logistic function was also fitted to the human data of Breysse and Swift [Aerosol Sci. Technol. 13, 459-464 (1990)] for comparison. The results suggest that ambient concentration is a good predictor (inhalability > 95%) of inhaled concentration for humans for particles < 11 microns dae. In small laboratory animals, however, the inhalable portion of the ambient concentration is predicted to be 95% for 0.7 microns dae particles but declines to 45% for 10 microns dae particles. It is, therefore, important to consider the effects of inhalability when estimating dose delivered to the target tissue in animals. In comparing delivered doses between animals and humans, adjusting for inhalability may change not only the magnitude of the difference but also which species is predicted to receive a greater delivered dose.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D010316	Particle Size	Relating to the size of solids.	Particle Sizes,Size, Particle,Sizes, Particle
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D004781	Environmental Exposure	The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals.	Exposure, Environmental,Environmental Exposures,Exposures, Environmental
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000393	Air Pollutants	Any substance in the air which could, if present in high enough concentration, harm humans, animals, vegetation or materials. Substances include GASES; PARTICULATE MATTER; and volatile ORGANIC CHEMICALS.	Air Pollutant,Air Pollutants, Environmental,Environmental Air Pollutants,Environmental Pollutants, Air,Air Environmental Pollutants,Pollutant, Air,Pollutants, Air,Pollutants, Air Environmental,Pollutants, Environmental Air
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D016015	Logistic Models	Statistical models which describe the relationship between a qualitative dependent variable (that is, one which can take only certain discrete values, such as the presence or absence of a disease) and an independent variable. A common application is in epidemiology for estimating an individual's risk (probability of a disease) as a function of a given risk factor.	Logistic Regression,Logit Models,Models, Logistic,Logistic Model,Logistic Regressions,Logit Model,Model, Logistic,Model, Logit,Models, Logit,Regression, Logistic,Regressions, Logistic