Comparative Pulmonary Toxicity of Various Soluble Metals Found in Urban Particulate Dusts

Abstract

The potential toxicity of an atmospheric dust sample EHC-93 has been attributed to the soluble fraction and, more specifically, to the zinc component. The concentration of Zn is the highest among the metals present in the soluble EHC-93 fraction. We now determine whether other metal components of this dust could cause similar lung injury if present at the same concentration as Zn (4.8 mg/g dust). Solutions of Zn, Cu, V, Ni, Fe, and Pb salts in 0.1 mL water were instilled to mouse lung and animals were killed at intervals up to 2 weeks later; each mouse received tritiated thymidine 1 hour before death. Solutions containing Zn and to a lesser degree Cu induced lung injury; in addition, increased numbers of alveolar macrophages and polymorphonuclear leukocytes were found in the lavage fluid, which also contained increased protein levels up to 1 week later. The magnitude of response was similar to that seen after administering EHC-93 dust at 1 mg in 0.1 mL water, whereas the response to other metal solutions containing Ni, Fe, Pb, and V was minimal. Morphologic evidence of lung injury and inflammation was also seen after EHC dust and the Zn or Cu solutions only. Reparative cell proliferation was measured after thymidine uptake and autoradiographs showed increased labeling of lung cells, particularly at 3 and 7 days. Labeling was confined to bronchiolar and type 2 alveolar epithelial cells, indicating previous epithelial cell necrosis in response to Zn or Cu. The results indicate that atmospheric contaminant metals Zn and Cu are most likely to cause lung injury and inflammation as compared to metals such as Ni, Fe, Pb, and V at the same concentrations. It appears that similar toxicity occurs when both redox (Cu) and nonredox (Zn) reactions are involved.

Probing the Structural Basis of Zn2+ Regulation of the Epithelial Na+ Channel

“…Although some metals are essential for normal physiological function, excessive environmental exposure can be toxic (16,17). For instance, particulate matter and airborne particles containing high amounts of transitional metals, including zinc and copper, contribute to pulmonary and cardiovascular toxicity (18,19). Although recent studies have suggested that ion channels are potential molecular targets of transition metals (20), the mechanisms that confer the harmful effects of heavy metals are poorly understood.…”

How a Steel Plant Affects Air Quality of a Nearby Urban Area: A Study on Metals and PAH Concentrations

“…The chemical composition of PM and particle size distributions are the most significant factors affecting air quality. In particular, the exposure to finer particles can cause short and long-term effects such as increased respiratory symptoms, decreased lung function, alterations in tissue and structure lung, in respiratory tract and premature death (Prieditis et al, 2002, Damek-Poprawa, 2003, Wahab et al, 2004, Huang and Ghio, 2006, Ahumada et al, 2007, Huang et al, 2007, Magas et al, 2007, Wild et al, 2009, Liuzzi et al, 2011. Moreover, near industrial areas, where elements and Polycyclic Aromatic Hydrocarbons (PAHs) are strongly associated with fine particles, increased toxicity and PM carcinogenicity have been determined (Bruno et al, 2002;Caselli et al, 2003;Pozzoli et al, 2004;Vione et al, 2004;Dvorskà et al, 2011;Castro-Jiménez et al, 2012;Tobiszewski and Namiesnik, 2012).…”

Efecto del sulfato de cobre en el daño pulmonar inducido por la exposición crónica intermitente a ozono

“…Los isoprostanos son considerados marcadores biológicos de estrés oxidativo, ya que se acumulan en estas condiciones 30 . El Cu +2 puede producir, por la reacción de Fenton, especies reactivas de oxígeno, que catalizan la formación de radicales hidroxilos a partir de peróxido de hidrógeno 6 . Además, puede participar en la reacción de Haber-Weiss, catalizando la formación de radicales hidroxilos a partir de peróxido de hidrógeno y anión superóxido 31,32 .…”

“…La instilación intratraqueal de igual concentración de distintos metales (4,8 µg de metal en 0,1 mL de agua) a ratas Spargue-Dawley detectó 48 h post-instilación que zinc y cobre inducen aumento de macrófagos alveolares y de leucocitos polimorfonucleares y de la concentración de proteínas en el lavado broncoalveolar, mientras que otros metales como vanadio, níquel, hierro y plomo, no provocaron cambios significativos [5][6][7][8] .…”