Spirometric data and penetration of particles to the alveoli

The percentage retention at 24 hours of 4 micron Teflon particles, aerodynamic diameter about 6 micron, was studied in 29 healthy male volunteers. The particles were inhaled at 0.5l/s with maximally deep breaths. The 24 hour retention correlated significantly with FEV1 and FVC and persisted when the subjects were divided into different categories according to profession and smoking habits. The results suggest that for exposure to metal particles at a size where impaction is an important deposition mechanism--that is, particles larger than a few microns--workers with large FEV1 values may run a greater risk of receiving systemic toxic effects than those with small FEV1 values.