Remember that since FCC availability data is currently processed biannually and only published six or more months later, data shown here may have minor inaccuracies. In summary, the majority of Arizona City homes have 4 options so far as residential Internet ( 4 in each census block), which is about average when contrasted with the US overall. Arizona City ranks 100th of 250 cities in Arizona in terms of broadband options. One of the best and concise reviews of what has been defined as asbestos is in a report by the U.S. Department of the Interior: U.S. Geological Survey by Virta.Underserved blocks are low, and only 10,000 are stuck with a single choice for Internet service. Briefly, asbestos and talc are minerals that are mined from the earth. The asbestos is defined as having six different types of magnesium (Mg) silicates (Si). An important feature of many of the types is that they may or may not contain iron when they are removed during mining. They can have other ions as well and those include sodium (Na) calcium (Ca) or manganese (Mn) along with the Mg and Si. These minerals are defined by the presence of these elements and their ratio one to another. There are numerous publications defining the mineralogic nature of these minerals throughout the literature besides what is stated in Virta. They are also defined initially by their color when in the ground and raw, by their size, shape, how they were formed and their crystalline structure by light and electron microscopy. The types are divided in two groups, serpentine and amphiboles. The serpentines principally are chrysotile and the amphiboles consist of five different types based on the ratio of the Mg to Si and other elements that are integrated into the molecular structure. The amphiboles consist of crocidolite, amosite, anthophyllite, tremolite and actinolite. They are mined in both open and closed type mines. The elemental composition of these six types of asbestos is seen in Table 1. The talc is a basic H 2Mg 3Si 4O 10(OH) 2. These mined minerals, both asbestos and talc, have in the past been used in many products and have been shown to have detrimental effects in humans and animals when they enter the body of these organisms. The effects range from tumors to fibrosis. The asbestos has been classified as a carcinogen and has been known to cause lung cancers, mesotheliomas, gastrointestinal cancers and more recently has been implicated in causing ovarian cancers and others. In the case of talc and talcum powder products, it has been implicated as causing these tumors either indirectly because it is contaminated with asbestos or the talc is a carcinogen or co-carcinogen even without the contaminating asbestos. Further, asbestos, generally in high doses is a well-known cause of interstitial fibrosis, asbestosis, and pleural plaques in lungs. Talc in relatively high doses is also known to cause fibrotic lesions, specifically in the lung. This type of fibrosis is referred to as granulomas. The mechanisms of causation of these diseases have been shown to be either direct or indirect. What I mean by direct is the interaction of the asbestos fiber or talc fiber or particle with DNA in the cell eliciting mutations.
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