Asbestos has been used by mankind for several thousand years, with the earliest written reference to asbestos being dated to approximately 300 B.C. There are also many documented references from the Roman Empire. The use of asbestos in building materials accelerated in the 1890's. The advancements in refining and manufacturing enabled the use of asbestos to expand to hundreds of industrial and commercial applications. And while these asbestos-containing products were (and still remain) some of the best available for their respective uses, this increased use of asbestos has enlarged the size of the population exposed to asbestos. The health effects associated with occupational and non-occupational asbestos exposure can create severe human diseases. Although asbestos continues to be used worldwide, the potential impact of these asbestos-caused diseases has motivated public health authorities of the United States to control the use of asbestos in this country. Ongoing federal and state programs oversee efforts to prevent environmental release, and abate existing asbestos sources.
Understanding, acceptance, and voluntary compliance with the federal and state regulations and recommended procedures regarding asbestos will prevent citations and fines, and tremendously reduce the risk of asbestos exposure.
The term asbestos refers to a group of naturally occurring silicate minerals. The most common types of asbestos minerals in this group are chrysotile, amosite, crocidolite, tremolite, anthophyllite, and actinolite. The first three listed (chrysotile, amosite, crocidolite) are the primary varieties used in commercial and industrial applications. Characteristics such as heat resistance, insulating abilities, fireproof, and chemical inertness, coupled with the flexibility to be woven make asbestos suitable for use in many applications.
While asbestos can enter the environment from weathered natural mineral deposits, our greatest concern for exposure in the workplace is fiber releases from manmade asbestos containing materials. Asbestos containing materials (ACM) include such products as floor tiles, adhesives, roof shingles, cements, acoustical and structural insulations, plumbing and electrical insulations, andautomotive brakes. Asbestos fibers may be released into the air when these products are disturbed.
The greatest concern regarding asbestos exposure is airborne asbestos fibers. Breathing asbestos containing air into the lungs will create the greatest potential for asbestos related disease. Some of the asbestos fibers reaching the lungs are exhaled as we breath, and others are coughed from the lungs with mucous, but the fibers reaching the deepest air passages of the lungs can produce the greatest damage.
The digestive system can be exposed to asbestos fibers from drinking water, mucous cleared from the lungs, and from eating food on which airborne asbestos fibers have settled. A small number of fibers may penetrate the cells that line the digestive system, but only a few will reach the bloodstream and be eliminated in the urine. Those fibers remaining in the digestive tract cells create a potential for asbestos related disease.
Asbestos fibers contacting the skin rarely pass through the skin into the body.
Information on human health effects of asbestos comes mostly from long-term studies of people (primarily miners, manufacturing workers, and construction trade workers) exposed to asbestos in the workplace. Persons who breathe in asbestos may develop a slow build-up of scar-like tissue in the lungs. This condition is called asbestosis. This scarred tissue impairs the ability of the lungs to absorb oxygen for the body. This is a serious disease and can eventually lead to disability and death. Persons who breathe in asbestos also have increased chances of developing two types of cancer: Lung cancer starts within the respiratory tissues, and mesothelial cancer grows from the membranes that surround the lungs and abdominal cavities. Both lung cancer and mesothelioma are usually fatal. These asbestos related diseases will not appear immediately, but may take from 10 to 50 years to develop following exposure.
NO. Asbestos exposure and disease is much like smoking and smoking related disease. The exposure increases the risk, but does not automatically mean that an individual will develop a related disease. Many people smoke for years, even a lifetime, and develop no smoking related disease. Others smoke for only a short period of time, yet develop a serious disease quickly. Asbestos exposure and related diseases mirror these examples. However, it does appear that exposure to high amounts of asbestos through either long term exposure and/or high concentrations is more serious. Research is currently underway to better determine the risks of short term and low concentration exposure to asbestos.
The most common test used to determine if you have been exposed to asbestos is a chest x-ray. The x-ray cannot detect the asbestos fibers themselves, but can detect early signs of lung disease caused by asbestos exposure. A pulmonary function test (PFT) determines lung capacity, and is another useful test in determining early signs of lung disease.
Periodic medical examinations including a chest x-ray, PFT, and a review of asbestos-based risk factors can be effective. Asbestos risk factors include length, levels, and frequency of asbestos exposure and smoking history. The combined impact of cigarette smoking and asbestos fiber exposure greatly increases the chances of lung disease.
Keep in mind that warnings are everywherein small print on the back of over-the-counter medications, on the side of every gas pump at the service station, on a tag at the end of every new hair blowdryer, and even on the plastic bag placed over our clean clothes at the dry cleaners. You should not be alarmed by warningsyou should respect them. Understand that the purpose of the warning is informational, and that a danger exists if item is misused or mistreated.
Most of the time, the answer to this question is NO. The most common asbestos containing materials used in the home are floor tile, roofing, and siding. These materials are very strong and don't readily crumble and release the asbestos fibers unless they are subjected to extremely strong forces. Occasionally other materials such as pipe insulation and thermal insulation are used in home construction. If you believe you may have these types of materials in your home, and you are considering renovation or demolition of the structure, you should seek the help of an asbestos consultant to aid you in determining the proper actions you need to take.
The Environmental Protection Agency (EPA) National Emission Standards for Hazardous Air Pollutants (NESHAP) requires that a survey be performed to determine the presence of asbestos in a building before any renovation or demolition work begins. In Texas, we also have the Texas Asbestos Health Protection Rules (TAHPR), which apply to public buildings. The Texas Department of Health (TDH) enforces TAHPR, and is also delegated, by the EPA, the authority to enforce NESHAP regulations. All of these regulations mentioned also require that notification be made before the start of any renovation or demolition project. In addition, TAHPR contains further requirements regarding licensing of companies and individuals that perform surveys and asbestos removal.
TAHPR requires licensing in the following categories: Contractors, Project Supervisors, Workers, Consultants, Management Planners, Inspectors, Air Monitors, Laboratories, Transporters, and Training Providers. To obtain a license, you must provide proof of appropriate training. All training and licensing is valid for periods of one year.
The Environmental Protection Agency (EPA) does not recommend that asbestos-containing materials (ACM) be removed for the sole purpose of removing the asbestos. Remember that the potential for an asbestos fiber release into the environment occurs when the asbestos containing material is disturbed. The EPA recommendations are to disturb the ACM only when necessary in the performance of operational & maintenance tasks, renovations, and demolition activity. And, of course, all applicable regulations and procedures must be adhered to, regardless of the reason for the disturbance.
For additional information regarding asbestos at UTSA and/or asbestos in general, please contact the Environmental & Construction Safety Coordinator.
Environmental & Construction Safety Coordinator