Elemental composition of ferruginous bodies and occupational categories: analyses and case studies in Mexico

Identification of ferruginous bodies in the lungs of children and analyses of the elemental composition of fibers

Ferruginous bodies (FBs) are iron-coated entities that form in the body around inorganic fibers or other particulates that can serve as indicators of exposure to inorganic dust. Studies of FB have been conducted consistently in the lungs of adults but have not been explored in children during the past 20 years. The objective of this work was to quantify the FB, classify them as to morphological type and conduct a mineralogical analysis using the energy dispersive X-ray microanalysis (EDXA) with samples obtained from 72 autopsies performed on children. Three grams of lung tissue were digested in commercial bleach, and all the FB found were quantified. The FB from the positive cases was analyzed by EDXA. Results show that 17% of cases presented FB with a median concentration of 5.7 ferruginous bodies per gram of dry weight (FB/g). Larger quantities of FB were recovered from the lungs of rural residents, at concentrations of 11.33 FB/g. Ten cases of children under 5 years of age also presented 5.7 FB/g, but none of these groups showed significant differences when compared to populations of children residing in Mexico City or to children over 5 years of age (p > 0.05). Type-1 FB was the predominant morphological form present. All FB were aluminosilicates. It can be concluded that Mexican children retain FB at low concentrations. All the cores of the FB analyzed in this study were aluminosilicates. Only one contained kaolinite, while the other 10 consisted of some kind of feldspar or clay-like mineral and may thus reflect intramural exposure in children.