Welding Fume Retention in Lungs of Previously Unexposed Subjects

Abstract

Previous studies of long-term exposed arc welders revealed gross differences in lung dust retention among arc welders. Explanations to this observation were sought e.g. in the time the welder had been exposed to arc welding fumes and the concentration of welding fume in the workshops. Even though these variables did explain some of the variability in the data, the remaining ratio between the welders having the highest retention to those having the lowest was over 50. Variables other than duration and intensity of the exposure could be responsible for this observation. Inter individual differences in retention pattern and clearance may explain some of the remaining variability. In this paper we describe a study addressing this question by measuring the rate of increase of retention in previously unexposed subjects being exposed to relatively homogeneous dust concentrations. The changes in retention is compared to the estimated individual exposure. A novel model for estimating individual retention and clearance is used.