Past asbestos exposure levels in foundries and cement-asbestos factories

While examining the literature referring to asbestos exposure among foundry workers, we were intrigued to come across a study dating from 1989 [Guillemin et al., 1989] on the presence of asbestos fibers in the urine of workers in a cement-asbestos factory where the controls were actually represented by foundry workers! The authors concluded that their "study did not prove with a sufficient level of statistical confidence that workers exposed to low levels of chrysotile asbestos excrete more fibers in urine than do non-exposed workers" (foundry workers). With the current state of our knowledge, it is not so hard to understand why. The study may now be interpreted as suggesting that foundry workers employed around that time suffered exposure levels not significantly dissimilar to those encountered by cement-asbestos factory workers.