Asbestos is a gristly mineral that is in chemical nature inert with added heat defiant properties. It has been utilized in over a wide spec of products of more than 3,000 products, counting fire resisting materials, cement, brake pads, plastics, paper products and textile products.
There are 2 forms of very usually used Asbestos, Serpentine and Amphibole. The Serpentine range of asbestos is termed as Chrysotile, where in turn the Amphibole range contains Crocidolite, Amosite, Anthophyllite, Actinolite and Tremolite.
Archetypal asbestos mining in the United States used open pit extraction followed by the milling process. Max out manufacture of asbestos in the United States was way over the 299 million pounds/year capacity in the late 1960s and early 1970s. Production deceased to 112 million pounds/year in 1987, to 37 million pounds/year in 1989, it stepped down to 30 million pounds/year in 1993, even to 15.4 million pounds/year in 1997, and as low as 13.2 million pounds/year in 1998 and 1999.
Asbestos are fibrous, naturally happening hydrated silicates that have long been mined and used for their fire-retardant and insulating properties as construction materials. Asbestos can be found in amphibole and serpentine forms. 95% of the asbestos mined globally is in a serpentine form of chrysotile type, with fibres that are long and curly. Amphibole forms of asbestos may be of amosite, crocidolite or anthophyllite types, and are shorter and straighter than serpentine varieties. According to the Stanton Hypothesis, amphibole fibres were originally thought to pose less risk, but these fibres were then linked to increased rates of mesothelioma.
Dr. Montague Murray first recognized the negative health effects of asbestos in 1899. However, dust control legislation for mines was not enacted in North America until 1971. In the middle years, mining and use of asbestos improved dramatically by 120-fold, peaking upon the enaction of legislation in 1971, and decreasing exponentially until the present. The current decreases in the rate of mining are due to public health concerns and to the increasingly more restrictive standards placed upon the level of asbestos dust allowed in mines, from 5 fibres/cm3 in 1971 to 1 fibres/cm3 at present although the global levels of asbestos mined have decreased significantly, Canada continues to be one of the world's foremost producers. 2.4 × 105 tonnes were mined in Canada in 2003, which accounted for much of the world's production of asbestos
What are the health effects of asbestos exposure?
Exposure to airborne friable asbestos may result in a potential health risk because persons breathing the air may breathe in asbestos fibers. Continued exposure can increase the amount of fibers that remain in the lung. Fibers embedded in lung tissue over time may cause serious lung diseases including: asbestosis, lung cancer, or mesothelioma. Smoking increases the risk of developing illness from asbestos exposure.
Adverse health effects from exposure to asbestos remain a serious concern to miners, mining communities and residents of buildings that contain asbestos. Miners and mining communities are at the greatest risk from asbestos related diseases, but are better ready to limit their exposure to asbestos than homeowners who are unknowingly breathing in asbestos. There is a time lag of 15 to 40 years between exposure and asbestos-caused disease for both residents and miners, which often makes it difficult to relate historical exposure to current symptoms. Asbestos has far-reaching and long-lasting impacts for human health, both through occupational and environmental exposure.
Three of the major health effects associated with asbestos exposure include:
Asbestosis – Asbestosis is a grave, progressive, long-term non-cancer disease of the lungs. It is caused by inhaling asbestos fibers that irritate lung tissues and cause the tissues to scar. The scarring makes it hard for oxygen to get into the blood. Symptoms of asbestosis include shortness of breath and a dry, crackling sound in the lungs while inhaling. There is no effective treatment for asbestosis.
Lung Cancer – Lung cancer causes the largest number of deaths related to asbestos exposure. People who work in the mining, milling, manufacturing of asbestos, and those who use asbestos and its products are more likely to develop lung cancer than the general population. The most common symptoms of lung cancer are coughing and a change in breathing. Other symptoms include shortness of breath, persistent chest pains, hoarseness, and anemia.
Mesothelioma – Mesothelioma is a rare form of cancer that is found in the thin lining (membrane) of the lung, chest, abdomen, and heart and almost all cases are linked to exposure to asbestos. This disease may not show up until many years after asbestos exposure. This is why great efforts are being made to prevent school children from being exposed.
Exposure to asbestos increases your risk of developing lung disease. That risk is made worse by smoking. In general, the greater the exposure to asbestos, the greater the chance of developing harmful health effects. Disease symptoms may take several years to develop following exposure. If you are concerned about possible exposure, consult a physician who specializes in lung diseases (pulmonologist).