Lead
Lead is a heavy metal that exists naturally in the earths crust. Lead has many industrial uses even though it can be catastrophically harmful to human life. The extensive use of lead has resulted in it widespread presence in the environment. People can be exposed to lead through occupational and environmental sources mainly from the inhalation of lead particles during smelting or the stripping of leaded paint, and ingestion of lead-contaminated dust, and water from lead pipes. Exposure can also come from cosmetics and some medicines. Young children are most vulnerable as they absorb 4 times as much ingested lead because of inherent curiosity, examples include picking and eating leaded paint from walls and ingesting contaminated soil. When lead enters the body it is distributed to organs like the kidneys, liver, and brain, the body will also store lead in the bones and teeth where it will accumulate over your lifetime. Lead exposure can also cause anemia, hypertension, and renal (kidney) impairment. With high levels of exposure lead will attack the brain and central nervous system causing convulsions, coma and death, yet at low levels exposure may produce no obvious symptoms at all. There is no known safe blood lead concentration, as exposure increases the severity of the symptoms and effects also increase. Behavioral and neurological effects are believed to be irreversible. Lead accumulates in bodies of water and soil organisms where animals and ocean life ingest it. Phytoplankton is a source of oxygen production in the ocean and many larger animals eat it. Soil organisms suffer from lead poisoning as well. Lead accumulates in individual organisms as well as an entire food chain. Romans were aware that lead could cause serious health problems, madness and death. Symptoms of lead poisoning were apparent as early as the first century B.C. The early 1920’s brought lead into gasoline and by 1924 the deadliness of tetraethyl lead was confirmed when 15 refinery workers died, the Surgeon General temporarily suspended production and sale of leaded gasoline. No compulsory standards were set until the early 1970s when the EPA (Environmental Protection Agency) began to phase down lead levels in US gasoline. In 1887, US medical authorities diagnosed a child with lead poisoning. In 1904, child lead poisoning was linking to lead based paints. In 1909, France, Belgium and Austria ban white lead interior paints. In 1921, national lead company admits lead is a poison. In 1922, league of nations ban all white lead interior paint however the US declines. In 1971, lead based paint poisoning prevention act is passed. In 1978, lead based paint is banned worldwide. Because of its effect of human health, lead was added to the Canadian Environmental Protection Act in 1988. In 2005, Health Canada initiated a rigorous review of the current toxicological and toxicokinetic data on lead to ensure that lead safety was being appropriately taken care of. Many alternative retailers carry alternatives to lead weights including those made of zinc, plastic, or steel. Even though some lead alternatives may be more environmentally friendly than others, scientists have big concerns about the elevated use of zinc and copper because of their toxic effects on plants and animals. |
Mercury
Mercury is a naturally occurring element that is found in the earths crust with natural deposits found as cinnabar. Mercury an exist in three different forms. Organic, inorganic, and elemental. In the environment, natural processes can change the form of mercury from one to another. Mercury is persistent and builds up in living organisms. The effects of mercury exposure can be very severe, subtle or may not occur at all. Health effects by exposure to mercury depends on the form of mercury, the amount in the exposure, the age of the person exposed, how long exposure lasts, how the person is exposed and the health of the person. A fetus is the most vulnerable to exposure. Methylmercury is a powerful neurotoxin, with symptoms such as loss of peripheral vision, the feeling of “pins and needles” in the hand feet and around the mouth, impaired speech, hearing and walking along with muscle weakness. Methylmercury affects people of all ages, almost all people have small amounts of methylmercury in their bodies. Exposure commonly occurs when people eat any kind of fish or shellfish. Elemental (Metallic) Mercury causes health effects mainly when inhaled as a vapor and symptoms include tremors, mood swings, muscle weakness, headaches, insomnia and poor performance of mental function. High exposure may also cause kidney problems such as increased protein in the urine to kidney failure, respiratory failure and death. Exposure mostly occurs when metallic mercury is spilled so that it is exposed to the air. Mercury is able to build up in organisms and up the food chain especially methylmercury it absorbs and accumulates to a greater extent than other forms. Smaller fish eat contaminated plankton then larger predatory fish eat the smaller fish in turn humans eat the fish. Mercury does not break down. Mercury has been identified as bad from times as early as that or the first emperor of china who died from taking mercury pills that were intended to make him immortal. People eventually started to noticed that the ingestion of mercury caused severe heath problems and death in many cases. The Canadian Environmental Protection Act of 1999 is an organization that is focused on pollution prevention and the protection of the environment as well as human health in order to contribute to sustainable development. On December 20, 2006, Environment Canada published a Rick Management Strategy for mercury containing products as a complement to the Government of Canada Chemical Management Plan. There are many alternatives to the usage of elemental mercury. These alternatives include:
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Asbestos
Asbestos is a commercial term given to six naturally occurring minerals that are incombustible and separable into filaments: chrysotile, amorite, crocidolite, anthophyllite, tremolite and actinolite. Asbestos is used in a wide range of practical application mainly as a reinforcing agent in the asbestos- cement industry as a fire retardant for paper products, friction products on breaks, as an agent to improve wear on vinyl floor tiles, and as filler is resin.
Health effects from long term asbestos exposure can cause fibrotic lung disease, asbestosis, and changes in the chest cavity. Both of these diseases can lead to reduced lung function, risk of lung cancer, mesothelioma and death. Increased resistance of blood flow through the lungs can cause enlargement of the heart.
Asbestosis is a lung disease where scar tissue is formed in the lungs called pulmonary fibrosis, fibrosis decreases the elasticity of the lungs making breathing harder, shortness of breath. Fully developed asbestosis patients experience shortness of breath, cough, chest pain and a blue skin colour, this normally requires many years of exposure.
“Naturally occurring asbestos” refers to the mineral as a natural component of soils or rocks. Naturally occurring asbestos can be released from rocks or soils by routine human activities, such as construction, or natural weathering processes. Asbestos when inhaled is toxic. Use of asbestos declined in the late 1970’s when it was discovered to be a threat to human safety, today it is known as a carcinogen.
The Occupational Health and Safety Act controls much of the rules and regulations of asbestos use in both commercial and personal usage.
Asbestos has many alternatives including polyurethane foams, flour fillers, cellulose fiber, thermoset plastic flour, and amorphous silica fabrics to help lower the usage of harmful asbestos in the environment.
Asbestos is a commercial term given to six naturally occurring minerals that are incombustible and separable into filaments: chrysotile, amorite, crocidolite, anthophyllite, tremolite and actinolite. Asbestos is used in a wide range of practical application mainly as a reinforcing agent in the asbestos- cement industry as a fire retardant for paper products, friction products on breaks, as an agent to improve wear on vinyl floor tiles, and as filler is resin.
Health effects from long term asbestos exposure can cause fibrotic lung disease, asbestosis, and changes in the chest cavity. Both of these diseases can lead to reduced lung function, risk of lung cancer, mesothelioma and death. Increased resistance of blood flow through the lungs can cause enlargement of the heart.
Asbestosis is a lung disease where scar tissue is formed in the lungs called pulmonary fibrosis, fibrosis decreases the elasticity of the lungs making breathing harder, shortness of breath. Fully developed asbestosis patients experience shortness of breath, cough, chest pain and a blue skin colour, this normally requires many years of exposure.
“Naturally occurring asbestos” refers to the mineral as a natural component of soils or rocks. Naturally occurring asbestos can be released from rocks or soils by routine human activities, such as construction, or natural weathering processes. Asbestos when inhaled is toxic. Use of asbestos declined in the late 1970’s when it was discovered to be a threat to human safety, today it is known as a carcinogen.
The Occupational Health and Safety Act controls much of the rules and regulations of asbestos use in both commercial and personal usage.
Asbestos has many alternatives including polyurethane foams, flour fillers, cellulose fiber, thermoset plastic flour, and amorphous silica fabrics to help lower the usage of harmful asbestos in the environment.