Ferruginous bodies as markers of environmental exposure to inorganic particles: experience with 270 autopsy cases in Mexico.

Ferruginous bodies (FB) were quantified in lung digests from 270 autopsy cases over 20 years of age. The cases were autopsied in three different hospitals of the Secretaria de Salud, Mexico, DF. Two hundred seventy samples of peripheral lung tissue were digested in commercial bleach, and all morphologic types of ferruginous bodies were quantified. The results showed that numbers of ferruginous bodies per gram of dry tissue increased over the years: 4.2 FB/g in cases from 1975 to 42.5 FB/g in cases from 1988 (r = 0.86). Higher counts of ferruginous bodies were seen in males, smokers, and Mexico City dwellers. However, more than 70% of them presented less than 100 FB/g. Our study demonstrates that most of our cases had a nonoccupational exposure to fibers.