Superfund Research Program
Toxicological Impact of Mine Tailings Dust on Lung Epithelial Barrier Function
In utero and/or early postnatal inhalation exposure of real world dusts collected at the Iron King Mine Superfund site leads to alterations in pulmonary function in adult animals. Continuous exposures from conception through early postnatal periods led to the greatest changes. Changes in lung function correlated with the greatest increases in protein biomarkers indicative of epithelial phenotype change. Alterations in lung function were comparable to those seen after inhalation of artificial dusts containing arsenicals. However, production of epithelial phenotypic biomarkers was much greater after inhalation of real world dusts compared to artificial dusts containing arsenicals alone. These data indicate that while arsenic inhalation by itself during early life can alter lung function, other constituents or characteristics of the real world dusts also contribute to phenotypic changes.
Early life exposures to arsenic affect lung function and biomarker expression in children exposed to high arsenic levels through drinking water. Lung function was significantly decreased and negatively associated with the percentage of urinary inorganic arsenic. The majority of subjects had alterations in lung function indicative of restricted lung expansion (restrictive pattern). The urinary arsenic level was higher in those children with restrictive lung patterns. Measurement of biomarkers in sputum from the highest exposed children indicated a pro-inflammatory environment within the lung. Arsenic-induced alterations in these inflammatory biomarkers are correlated with the decrement in lung function and may contribute to the development of arsenic-induced restrictive lung diseases following in utero and early childhood exposures (Recio-Vega et al 2015; Olivas-Calderón et al 2015).