Asbestos resources Pt 1-3
The controversy surround asbestos is long standing and wide, with one camp stating they have worked with or around the material for years and never had a problem, while others take a 180 degree from that with a level of fear that rivals a nuclear power plant accident.
It is true, a certain percentage of people can supposedly be around asbestos for years and not show any outward signs of the health issues, while other people- another percentage- contracts cancers and other health issues from unknown causes while in their 20s, 30s and 40s.
The third percentage of the population- the majority, may or may not develop cancer or lung diseases from asbestos, or health problems from lead paint, coal dust, or any of the scores of chemicals and substances everyone is exposed to from birth. There is no test available to determine if a person is especially sensitive to asbestos, lead etc or if they are not, just as some smokers can smoke six packs of Marlboro filterless for 50 years and live to be 96, while others who never smoked in their lives get lung cancer in their 40s
There is no KNOWN safe level of exposure to asbestos, in theory ONE fiber could be the cause of a tumor later on.
It can be found in linoleum floor tiles, pipe insulation, vermiculite attic insulation, old cementious materials and sheets and many others.
What is different about asbestos is the fact that under the microscope, the observer will see the mineral is made up of needle-like particles.
All six asbestos mineral types are known to be human carcinogens.
Chrysotile has been used more than any other type and accounts for about 95% of the asbestos found in buildings in America.
Chrysotile is more flexible than amphibole types of asbestos, and can be spun and woven into fabric. Its most common use has been in corrugated asbestos cement roof sheets typically used for outbuildings, warehouses and garages. It may also be found in sheets or panels used for ceilings and sometimes for walls and floors. Chrysotile has been a component in joint compound and some plasters. Numerous other items have been made containing chrysotile, including brake linings, fire barriers in fuseboxes, pipe insulation, floor tiles, roofing tars, felts, siding, and shingles, and rope seals for boilers.
The first documented death related to asbestos was in 1906. In the early 1900s researchers began to notice a large number of early deaths and lung problems in asbestos mining towns. The first diagnosis of asbestosis was made in the UK in 1924. By the 1930s, the UK regulated ventilation and made asbestosis an excusable work-related disease, followed by the U.S about ten years later. The term mesothelioma was first used in medical literature in 1931; its association with asbestos was first noted sometime in the 1940s.
Approximately 100,000 people in the United States have died, or are terminally ill, from asbestos exposure related to ship building. In the Hampton Roads area, a shipbuilding center, mesothelioma occurrence is seven times the national rate. Thousands of tons of asbestos were used in World War II ships to wrap the pipes, line the boilers, and cover engine and turbine parts. There were approximately 4.3 million shipyard workers in the United States during WWII; for every thousand workers about fourteen died of mesothelioma and an unknown number died from asbestosis.
The United States government and asbestos industry have been criticized for not acting quickly enough to inform the public of dangers, and to reduce public exposure. In the late 1970s court documents proved that asbestos industry officials knew of asbestos dangers since the 1930s and had concealed them from the public.
Through the 1970s, asbestos was used to fireproof roofing and flooring, for heat insulation, and for a variety of other purposes.
W.R. Grace's vermiculite mine was known for years to be contaminated by asbestos, vermiculte was packaged in bags and sold to consumers and contractors world-wide as a cheap attic insulation, the material contaminated rail stations, homes, businesses and more everywhere it was shipped and used. This company filed for bankruptcy when the asbestos litigation, cleanup and lawsuits began, and then reorganized and returned to business.
Fibers ultimately form because when these minerals originally cooled and crystallized, they formed by the polymeric molecules lining up parallel with each other and forming oriented crystal lattices. These crystals thus have three cleavage planes, and in this case, there are two cleavage planes which are much weaker than the third. When sufficient force is applied, they tend to break along their weakest directions, resulting in a linear fragmentation pattern and hence a fibrous form. This fracture process can keep occurring and one larger asbestos fiber can ultimately become the source of hundreds of much thinner and smaller fibers.
Asbestos exposure becomes an issue if asbestos containing materials become airborne, such as due to deterioration or damage. Building occupants may be exposed to asbestos, but those most at risk are persons who purposely disturb materials, such as maintenance/construction workers. Housekeeping/custodial employees may be at increased risk as they may potentially clean up damaged or deteriorated asbestos containing materials without knowing that the material contains asbestos. Asbestos abatement/remediation workers and emergency personnel such as firefighters may also become exposed. Asbestos-related diseases have been diagnosed in asbestos workers' family members, and in residents who live close to asbestos mines or processing plants.
Early concern in the modern era on the health effects of asbestos exposure can be found in several sources. Among the earliest were reports in Britain. The annual reports of the Chief Inspector of Factories reported as early as 1898 that asbestos had "easily demonstrated" health risks.
At about the same time, what was probably the first study of mortality among asbestos workers was reported in France. While the study describes the cause of death as chalicosis, a generalized pneumoconiosis, the circumstances of the employment of the fifty workers whose death prompted the study suggest that the root cause was asbestos or mixed asbestos-cotton dust exposure.
London doctor H. Montague Murray conducted a post mortem exam on a young asbestos factory worker who died in 1899. Dr. Murray gave testimony on this death in connection with an industrial disease compensation hearing. The post-mortem confirmed the presence of asbestos in the lung tissue, prompting Dr. Murray to express as an expert opinion his belief that the inhalation of asbestos dust had at least contributed to, if not actually caused, the death of the worker.
Widespread recognition of the occupational risks of asbestos in Britain was reported in 1924 by a Dr. Cooke, a pathologist, who introduced a case description of a 33-year-old female asbestos worker, Nellie Kershaw, with the following: "Medical men in areas where asbestos is manufactured have long suspected the dust to be the cause of chronic bronchitis and fibrosis ..." Dr. Cooke then went on to report on a case in 1927 involving a 33-year-old male worker who was the only survivor out of ten workers in an asbestos carding room. In the report he named the disease "asbestosis".
Dr. Cooke's second case report was followed, in the late 1920s, by a large public health investigation (now known as the Merewether report after one of its two authors) that examined some 360 asbestos-textile workers (reported to be about 15% of the total comparable employment in Britain at the time) and found that about a quarter of them suffered from pulmonary fibrosis.
Female operator Clemance Gagnon watches a machine carding asbestos fiber for spinning and processing at the Johns-Manville factory.
Credit:
Harry Rowed. National Film Board of Canada. Photothèque. Library and Archives Canada, PA-115069 /
The controversy surround asbestos is long standing and wide, with one camp stating they have worked with or around the material for years and never had a problem, while others take a 180 degree from that with a level of fear that rivals a nuclear power plant accident.
It is true, a certain percentage of people can supposedly be around asbestos for years and not show any outward signs of the health issues, while other people- another percentage- contracts cancers and other health issues from unknown causes while in their 20s, 30s and 40s.
The third percentage of the population- the majority, may or may not develop cancer or lung diseases from asbestos, or health problems from lead paint, coal dust, or any of the scores of chemicals and substances everyone is exposed to from birth. There is no test available to determine if a person is especially sensitive to asbestos, lead etc or if they are not, just as some smokers can smoke six packs of Marlboro filterless for 50 years and live to be 96, while others who never smoked in their lives get lung cancer in their 40s
There is no KNOWN safe level of exposure to asbestos, in theory ONE fiber could be the cause of a tumor later on.
Asbestos is a naturally occurring mineral which was discovered to have great resistance to heat and chemicals, it was as a result incorporated in thousands of buildings products, components and articles used by people.
It can be found in linoleum floor tiles, pipe insulation, vermiculite attic insulation, old cementious materials and sheets and many others.
What is different about asbestos is the fact that under the microscope, the observer will see the mineral is made up of needle-like particles.
All six asbestos mineral types are known to be human carcinogens.
Chrysotile has been used more than any other type and accounts for about 95% of the asbestos found in buildings in America.
Chrysotile is more flexible than amphibole types of asbestos, and can be spun and woven into fabric. Its most common use has been in corrugated asbestos cement roof sheets typically used for outbuildings, warehouses and garages. It may also be found in sheets or panels used for ceilings and sometimes for walls and floors. Chrysotile has been a component in joint compound and some plasters. Numerous other items have been made containing chrysotile, including brake linings, fire barriers in fuseboxes, pipe insulation, floor tiles, roofing tars, felts, siding, and shingles, and rope seals for boilers.
The first documented death related to asbestos was in 1906. In the early 1900s researchers began to notice a large number of early deaths and lung problems in asbestos mining towns. The first diagnosis of asbestosis was made in the UK in 1924. By the 1930s, the UK regulated ventilation and made asbestosis an excusable work-related disease, followed by the U.S about ten years later. The term mesothelioma was first used in medical literature in 1931; its association with asbestos was first noted sometime in the 1940s.
Approximately 100,000 people in the United States have died, or are terminally ill, from asbestos exposure related to ship building. In the Hampton Roads area, a shipbuilding center, mesothelioma occurrence is seven times the national rate. Thousands of tons of asbestos were used in World War II ships to wrap the pipes, line the boilers, and cover engine and turbine parts. There were approximately 4.3 million shipyard workers in the United States during WWII; for every thousand workers about fourteen died of mesothelioma and an unknown number died from asbestosis.
The United States government and asbestos industry have been criticized for not acting quickly enough to inform the public of dangers, and to reduce public exposure. In the late 1970s court documents proved that asbestos industry officials knew of asbestos dangers since the 1930s and had concealed them from the public.
Through the 1970s, asbestos was used to fireproof roofing and flooring, for heat insulation, and for a variety of other purposes.
W.R. Grace's vermiculite mine was known for years to be contaminated by asbestos, vermiculte was packaged in bags and sold to consumers and contractors world-wide as a cheap attic insulation, the material contaminated rail stations, homes, businesses and more everywhere it was shipped and used. This company filed for bankruptcy when the asbestos litigation, cleanup and lawsuits began, and then reorganized and returned to business.
Fibers ultimately form because when these minerals originally cooled and crystallized, they formed by the polymeric molecules lining up parallel with each other and forming oriented crystal lattices. These crystals thus have three cleavage planes, and in this case, there are two cleavage planes which are much weaker than the third. When sufficient force is applied, they tend to break along their weakest directions, resulting in a linear fragmentation pattern and hence a fibrous form. This fracture process can keep occurring and one larger asbestos fiber can ultimately become the source of hundreds of much thinner and smaller fibers.
A fiber cannot be identified or ruled out as asbestos, either using the naked eye or by simply looking at a fiber under a regular microscope. Some older products may or may not contain asbestos, for example- not all linoleum floor tiles used it.
Asbestos exposure becomes an issue if asbestos containing materials become airborne, such as due to deterioration or damage. Building occupants may be exposed to asbestos, but those most at risk are persons who purposely disturb materials, such as maintenance/construction workers. Housekeeping/custodial employees may be at increased risk as they may potentially clean up damaged or deteriorated asbestos containing materials without knowing that the material contains asbestos. Asbestos abatement/remediation workers and emergency personnel such as firefighters may also become exposed. Asbestos-related diseases have been diagnosed in asbestos workers' family members, and in residents who live close to asbestos mines or processing plants.
By the first century AD, Greeks and Romans are claimed to have observed that slaves involved in the weaving of asbestos cloth were afflicted with a sickness of the lungs.
Early concern in the modern era on the health effects of asbestos exposure can be found in several sources. Among the earliest were reports in Britain. The annual reports of the Chief Inspector of Factories reported as early as 1898 that asbestos had "easily demonstrated" health risks.
At about the same time, what was probably the first study of mortality among asbestos workers was reported in France. While the study describes the cause of death as chalicosis, a generalized pneumoconiosis, the circumstances of the employment of the fifty workers whose death prompted the study suggest that the root cause was asbestos or mixed asbestos-cotton dust exposure.
London doctor H. Montague Murray conducted a post mortem exam on a young asbestos factory worker who died in 1899. Dr. Murray gave testimony on this death in connection with an industrial disease compensation hearing. The post-mortem confirmed the presence of asbestos in the lung tissue, prompting Dr. Murray to express as an expert opinion his belief that the inhalation of asbestos dust had at least contributed to, if not actually caused, the death of the worker.
Widespread recognition of the occupational risks of asbestos in Britain was reported in 1924 by a Dr. Cooke, a pathologist, who introduced a case description of a 33-year-old female asbestos worker, Nellie Kershaw, with the following: "Medical men in areas where asbestos is manufactured have long suspected the dust to be the cause of chronic bronchitis and fibrosis ..." Dr. Cooke then went on to report on a case in 1927 involving a 33-year-old male worker who was the only survivor out of ten workers in an asbestos carding room. In the report he named the disease "asbestosis".
Dr. Cooke's second case report was followed, in the late 1920s, by a large public health investigation (now known as the Merewether report after one of its two authors) that examined some 360 asbestos-textile workers (reported to be about 15% of the total comparable employment in Britain at the time) and found that about a quarter of them suffered from pulmonary fibrosis.
Female operator Clemance Gagnon watches a machine carding asbestos fiber for spinning and processing at the Johns-Manville factory.
Credit:
Harry Rowed. National Film Board of Canada. Photothèque. Library and Archives Canada, PA-115069 /