Inhalable dust spectrometers as versatile samplers for studying dust-related health effects

This paper extends the idea, presented in an earlier communication, that dust sampling for studying health effects should take account of aerodynamic processes both inside and outside the body. A rationale is described for the inhalable dust spectrometers which have been suggested as samplers to be used in new epidemiological enquiries. By means of these versatile instruments, it is possible in principle to obtain the aerodynamic size distribution and airborne mass concentration of particles contained within the inhalable fraction and then within any number of chosen deposition sub-fractions. The basic raw data, suitably stored, may be used and re-used retrospectively to provide information about sub-fractions whose definitions are not yet known or which might be changed in the light of new experimental lung deposition evidence. By way of illustration, some typical results obtained using a new inhalable dust spectrometer in a coal mine are used to examine the effect of changing breathing pattern on the dust dose received by the respiratory regions of the lungs of exposed workers.