Altered inorganic composition of enamel and dentin in mice teeth chronically exposed to an enriched mineral environment at Furnas, São Miguel (Azores)
Luís Cunha, V. Zanon, A. Amaral, J. Ferreira & A. Rodrigues
Geothermal biotopes are reducing environments with certain unique features, characterised by elevated soil, water, and atmospheric elemental composition, together with constant diffuse degassing and high temperatures (Cruz et al. 1999; Viveiros et al. 2008; Viveiros et al. 2009). Volcanic gases typically comprise water vapour, carbon dioxide, sulphur dioxide, hydrogen sulphide, and hydrogen chloride with lesser amounts of hydrogen fluoride (Ferreira & Oskarsson 1999). Rocks and volatiles of volcanic origin are enriched with metals/metalloids, such as Al, As, Cu, Hg, Pb, and Zn (Aiuppa et al. 2000; Bagnato et al. 2007; Cruz et al. 1999). The diffusion of acidic volcanic gases through the rocks mobilise metals in associated soils and water bodies, enhancing a continuous availability of elements to biota (Cunha et al. 2008; Cunha et al. 2011; Tarasov et al. 2005).
Exposure to such environments is revealed by high levels of bioaccumulated elements such as heavy metals, modified cell cycles or even tissue/cell morphometric changes (Moore et al. 1995; Zaldibar et al. 2006). Furthermore, a number of human and domestic mammal diseases, such as fluorosis, several types of cancer and 33 chronic bronchitis seem to be more prevalent in volcanic environments or even increase after volcanic eruptions (Amaral & Rodrigues 2007; Araya et al. 1993).
The composition and structure of calcified tissues have long been used as disease markers (Emingil et al. 2000; Paunio et al. 1993) as well as indicators of environmental contamination (Kierdorf et al. 1993). Additionally, tooth discoloration has been widely used as a marker of fluorosis, revealed by the mottling of tooth enamel (Rubin et al. 1994).
This study aimed to investigate whether individuals of Mus musculus (Linnaeus, 1758) exposed to an extreme environment of volcanic origin revealed alterations in the mineral composition and surface coloration of a calcified matrix, such as permanent teeth.