Influence of Breathing Mode and Activity Level on the Regional Deposition of Inhaled Particles and Implications for Regulatory Standards (March 1986)

摘要

Particulate size-selective sampling is an important consideration in determining ambient air quality standards and threshold limit values for workplace exposures. Hazard evaluations, as well as risk analyses, can benefit from an improved understanding of factors affecting regional respiratory tract deposition of particles in man. Here, thoracic deposition and its component parts are examined, as a function of particulate size, for ventilation rates ranging from normal respiration to heavy exercise in individuals who are habitual mouth breathers and in those who normally employ oronasal breathing when minute ventilations exceed approximately 35 Lmin-1. Nonlinear regression techniques were used to fit logistic models of the form Y = (1+e alpha+beta log X)-1 to data from tests measuring extrathoracic (ET) and tracheobronchial (TB) deposition.