Synergistic effect of air pollution and habitual smoking on the retention of inorganic fibers identified as ferruginous bodies in autopsy cases in Mexico City

Abstract

In order to evaluate the synergistic effect of habitual smoking and air pollution in Mexico City on the retention of inorganic fibers, ferruginous bodies (FB) were quantified as markers of exposure to inorganic fibers in lung digests from 426 autopsy cases. FB were isolated from 426 lung digests from cases with several lung diseases. The results revealed more retention of FB in the smokers group than in non-smokers: 38 FB per gram (FB/g) versus 11.2 FB/g, respectively (p < 0.05). Male smokers living in Mexico City increased their median to 54 FB/g. This contrasts with the median of outside residents: 11.2 FB/g (p < 0.002). Housewives and manual laborers increased their medians when the smoking habit was positive: from 11 to 14 FB/g, and from 16 to 21.5 FB/g, respectively. There is an effect of tobacco smoke on the retention of more fibers identified as FB when the individuals are males and Mexico City residents.

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

“…AB are recognized as FB and are typified by their characteristic appearance under light microscopy: fibers that are straight and transparent. Quantified results show that smokers generally have higher concentrations of AB and FB than nonsmokers (Churg & Warnock, 1977;Arenas-Huertero et al, 1994;Salazar-Flores et al, 2009); in fact, in a study conducted in Mexico based on the evaluation of autopsy cases, Salazar-Flores et al (2009) verified the existence of a synergic effect between air pollution in Mexico City and smoking that led to a high retention of FB, especially among men. In their study, the authors demonstrated that male residents of Mexico City who smoked presented a mean of 54 FB/g (FB per gram of dry tissue), compared to 34 FB/g in nonsmoking men there, and to the 11 FB/g found in nonsmokers in rural areas.…”

“…This effect of augmenting FB retention is strongly linked to the number of cigarettes smoked, especially when consumption exceeds 300 packs per year. Environmental exposure to asbestos or other, similar, materials also occurs naturally, as shown by the fact that people from rural areas (Breedin & Buss, 1976) may have similar concentrations of FB to those found in nonsmokers in Mexico City (Salazar-Flores et al, 2009). As FB may be present in almost any individual, and given the severity of the problems of pollution in large urban areas like Mexico City, it is important to conduct both descriptive and quantitative studies that will enable us to better understand the possible magnitude of such exposures, gain a clearer idea of their effects, and evaluate the relation between this factor and the incidence of pulmonary disease (Roggli, 2004).…”

“…All the aforementioned information clearly indicates that it is necessary to continue monitoring and doing follow-up on these FB markers in order to determine their presence, concentrations, tendencies, and characteristics in relation to specific demographic groups. Moreover, it suggests that the process of forming FB constitutes a protective mechanism developed by the lungs to reduce the toxicity of such fibers (Salazar-Flores et al, 2009). Unfortunately, this process entails transforming ferritin into hemosiderin, which exposes the lungs to iron, thus increasing the risk of suffering oxidative stress.…”

“…Elemental composition of ferruginous bodies and occupational categories: analyses and case studies in Mexico David Villeda-Cuevas 1,2 , David Quintero-Casas 1,2 , Rosa Maria Rivera-Rosales 3 , Pilar Eguía-Aguilar 1 , Mario Perezpeña-Diazconti 1 , and Francisco Arenas-Huertero 1,2 1994; Salazar-Flores et al, 2009). Analyses of the concentrations of FB from the cases studied in relation to occupation reveals that men working in manual jobs not related to construction in public establishments -all belonging to the category "blue collar, " as per Churg and Warnock (1977) -tend to have higher concentrations of FB, a finding that reflects greater exposure to inorganic fibers in this occupational sub-type (Roggli, 2004).…”

“…This complex mixture of atmospheric pollutants includes gases, smoke, heavy metals (in decline), polycyclic aromatic hydrocarbons, secondary contaminants, biological pollutants, and suspended particles (Salazar-Flores et al, 2009). Since 1994, our work group has been devoted to analyzing and following up on trends in the retention of inorganic fibers that appear as ferruginous bodies (FB) inside the human lung, primarily among residents of Mexico City (Arenas-Huertero et al, 1994).…”