Pollutants are substances which directly or indirectly damage humans or the environment. Many of the compounds which are dangerous to the environment can also be harmful to humans in the long-term range and come from mineral and fossil sources or are produced by humans itselfs.
Pollutants can cause the destruction of areas of the environment which are essential to us and also many pollutants have a poisonous effect on the body. Some compounds like asbestos, carbon dioxide or nitrates occurs naturally and might be essential for life. This compounds can be released or are produced by humans, causing an imbalance of the natural processes. In the United States, asbestos, a naturally occurring fibrous mineral, was one of the first hazardous air pollutants regulated under Section 112 of the Clean Air Act of 1970.
As early as 1898 the Chief Inspector of Factories of the United Kingdom reported to Parliament in his Annual Report about the "evil effects of asbestos dust". He reported the "sharp, glass like nature of the particles" when allowed to remain in the air in any quantity, "have been found to be injurious, as might have been expected" (Report of the Select Committee 1994). In 1906 a British Parliamentary Commission confirmed the first cases of asbestos deaths in factories in Britain and recommended better ventilation and other safety measures. In 1918 a US insurance company produced a study showing premature deaths in the asbestos industry in the United States and in 1926 the Massachusetts Industrial Accidents Board processed the first successful compensation claim by a sick asbestos worker. Many American injuries from asbestos exposure came from shipbuilders working during World War II.
The problem with asbestos arises when the fibers become airborne and are inhaled. Because of the size of the fibers, the lungs cannot expel them. [Casarrett & Doull's Toxicology (2001), pp 520-522]
Diseases caused by asbestos include:
Asbestosis – A lung disease first found in naval shipyard workers, asbestosis is a scarring of the lung tissue from an acid produced by the body's attempt to dissolve the fibers. The scarring may eventually become so severe that the lungs can no longer function. The latency period (the time it takes for the disease to develop) is often 10-20 years.
Mesothelioma – A cancer of the mesothelial lining of the lungs and the chest cavity, the peritoneum (abdominal cavity) or the pericardium (a sac surrounding the heart). The only known cause is from asbestos exposure. The latency period for mesothelioma may be 20-50 years. The prognosis for mesothelioma is grim, with most patients dying within 12 months of diagnosis.
Cancer – Cancer of the lung, gastrointestinal tract, kidney and larynx have been linked to asbestos. The latency period for cancer is often 15-30 years.
In the United States alone, ten thousand people die each year of asbestos-related diseases, such as mesothelioma, asbestosis, lung cancer, and gastrointestinal cancer. Asbestos also has a synergistic effect with tobacco smoking in the causation of lung cancer.
Benzene exposure has serious health effects. Breathing high levels of benzene can result in death, while high levels can cause drowsiness, dizziness, rapid heart rate, headaches, tremors, confusion, and unconsciousness. Eating or drinking foods containing high levels of benzene can cause vomiting, irritation of the stomach, dizziness, sleepiness, convulsions, rapid heart rate, and death.
The major effect of benzene from chronic (long-term) exposure is to the blood. Benzene damages the bone marrow and can cause a decrease in red blood cells, leading to anemia. It can also cause excessive bleeding and depress the immune system, increasing the chance of infection.
Some women who breathed high levels of benzene for many months had irregular menstrual periods and a decrease in the size of their ovaries. It is not known whether benzene exposure affects the developing fetus in pregnant women or fertility in men.
The US Department of Health and Human Services (DHHS) classifies benzene as a human carcinogen. Long-term exposure to high levels of benzene in the air can cause leukemia, a potentially fatal cancer of the blood-forming organs. In particular, Acute Myeloid Leukemia (AML) may be caused by benzene.
Eating food or drinking water contaminated with high levels of creosotes may cause a burning in the mouth and throat, and stomach pains.
Brief direct contact with large amounts of coal tar creosote may result in a rash or severe irritation of the skin, chemical burns of the surfaces of the eyes, convulsions and mental confusion, kidney or liver problems, unconsciousness, and even death. Longer direct skin contact with low levels of creosote mixtures or their vapors can result in increased light sensitivity, damage to the cornea, and skin damage. Longer exposure to creosote vapors can cause irritation of the respiratory tract.
Long-term exposure to low levels of creosote, especially direct contact with the skin during wood treatment or manufacture of coal tar creosote-treated products has resulted in skin cancer and cancer of the scrotum. Cancer of the scrotum in chimney sweeps has been associated with long-term skin exposure to soot and coal tar creosotes. Animal studies have also shown skin cancer from skin exposure to coal tar products.
The International Agency for Research on Cancer (IARC) has determined that coal tar is carcinogenic to humans and that creosote is probably carcinogenic to humans. The EPA has determined that coal tar creosote is a probable human carcinogen.
Pesticide Birth Defects
It is critical, when pesticide poisoning is suspected, to get competent treatment as rapidly as possible. Since pesticides have different modes of action and different medical responses, it is also necessary to refer to the label. If you are using a pesticide, be sure a copy of the label is present and accessible before you begin use. If you are rendering first aid, if at all possible, obtain a copy of the pesticide label for yourself and for the medical personnel.
If one is regularly using carbamate and organophosphate pesticides, it is important to obtain a baseline cholinesterase test. Cholinesterase is an important enzyme of the nervous system, and these chemical groups kill pests, and potentially injure or kill humans by inhibiting cholinesterase. If one has a baseline test, and suspects a poisoning, one can identify the extent of it by comparison of the current cholinesterase level with the baseline level.
How poisonings occur:
Pesticides can enter the body from inhalation, ingestion, or eye or skin contact. Many cases of poisoning occur to applicators without proper protection. Another scenario is that pesticides are directly applied to farmworkers in the field, or that they re-enter treated field before the toxicity levels drop to acceptable levels.
Children more vulnerable than adults (placeholder)
Symptoms of pesticide poisoning (placeholder)
First aid for poisoning victims (placeholder
Although silicosis has been known for centuries, the industrialization of mining has led to an increase in silicosis cases. In the United States, a 1930 epidemic of silicosis due to the construction of the Hawk's Nest Tunnel near Gauley Bridge, West Virginia caused the death of more than 400 workers.
Also, the mining establishment of Delamar Ghost Town, Nevada was ruined by a dry-mining process that produced a silicosis-causing dust. After hundreds of deaths from silicosis, the town was nicknamed The Widowmaker.
Indeed, silicosis is an occupational hazard to mining, sandblasting, quarry and foundry workers, as well as grinders, stonecutters and those continually exposed to silica dust.
Protective measures such as respirators have brought a steady decline in death rates due to silicosis in Western countries. Unfortunately, this is not true of less developed countries where work conditions are poor and respiratory equiptment is seldom used. For instance, life expectancy for silver miners in Potosí, Bolivia is around 40 years due to silicosis.
While Teflon itself is chemically inert and non-toxic, Teflon begins to deteriorate after the temperature of cookware reaches about 500°F (260°C), and begins to significantly decompose above 660°F (350°C). These degradation products can be lethal to birds, and can cause flu-like symptoms in humans (see Teflon flu). By comparison, cooking fats, oils and butter will begin to scorch and smoke at about 392°F (200°C), and meat is usually fried between 400–450°F (200–230°C), but empty cookware can exceed this temperature if left unattended on a hot burner. A 1959 study, conducted before the FDA approved the material for use in food processing equipment, showed that the toxicity of fumes given off by the coated pan on dry heating was less than that of fumes given off by ordinary cooking oils.
The EPA's scientific advisory board found in 2005 that perfluorooctanoic acid (PFOA), a chemical compound used to make Teflon, is a "likely carcinogen." This finding was part of a draft report that has yet to be made final. DuPont settled for $300 million in a 2004 lawsuit filed by residents near its manufacturing plant in Ohio and West Virginia based on groundwater pollution from this chemical. Currently this chemical is not regulated by the EPA.
In January 2006, DuPont, the only company that manufactures PFOA in the US, agreed to eliminate releases of the chemical from its manufacturing plants by 2015, but did not commit to completely phasing out its use of the chemical.