Wednesday, August 14, 2019
Toxic Chemicals
Toxic Chemicals are substances naturally produced by the environment naturally or artificially produced by industrial manufactures.. The chemicals produced that have been around since the industrial age began are considered hazardous both to us and the environment. Some of the most highly toxic chemicals used today include polychlorinated biphenyls(PCB's), chlorofluorocarbons(CFC) and polyvinyl chloride(PVC's). These chemicals can be found in such products such as nuclear waste and automobile tires. Toxic chemicals or pollutants are substances that enter the environment through industrial, agricultural, or other human-generated processes that pose health hazards to humans, animals, and plants. This paper will look directly at chemicals which have been discovered to be hazardous or toxic, that are produced in quantity, and are difficult or extremely costly to remove once introduced to the environment. Nuclear waste is produced throughout the entire nuclear fuel cycle, beginning with the mining of uranium to the reprocessing of irradiated nuclear fuel. Nuclear waste will remain hazardous for thousands of years, leaving a poisonous legacy for future generations. As part of the normal routine operations of every nuclear power station some waste materials are discharged into the environments directly. Liquid waste is discharged using turbine cooling water to carry the waste into a nearby stream or river. Gaseous toxins are released into the atmosphere. There are three categories of radioactive nuclear waste; High level waste (HLW), Intermediate level Waste (ILW) and Low level waste (LLW). HLW consists mainly of irradiated fuel from the cores of nuclear reactors (although the nuclear industry does not consider this to be a waste) and high-levels of liquid waste are produced during reprocessing. The deadly wastes produced from these producers, are stored in large tanks, and are mixed with a hot glass material for solidification purposes. These glass logs also being classified as HLW. While the glassification process may make it easier to transport and store nuclear waste, it does not diminish the terrible dangers that the public and the environment are exposed too. HLW is typically a thousand times more radioactive than ILW. ILW consists mainly of metallic fuel ââ¬Ëcans' which originally contained uranium fuel for that was used by nuclear power stations, reactor metalwork and chemical residues. ILW must be contained and from workers and the public exposure during transport and disposal. It is usually stored at the site of production. ILW is typically a thousand times more radioactive that LLW. LLW can be defined as waste which does not require protective shielding during normal handling and transportation. Examples of products containing LLW chemicals include protective clothing and laboratory equipment which have come into contact with radioactive materials. When disposing of highly radioactive nuclear fuel, the ââ¬Å"spentâ⬠fuel is removed from the reactor and is stored temporarily in water-filled cooling pools. As the cooling pools are filled, many nuclear sites will have to shut down due to this lack of storage space for the deadly waste. According to estimates by the International Atomic Energy Agency (IAEA), the global amount of ââ¬Å"spentâ⬠fuel in 1992 was estimated at125,000 tonnes. It is projected that by the year 2000 the annual spent fuel world wide will be over 200,000 tonnes, and 450,000 tonnes by the year 2030. Although a variety of disposal methods have been discussed for decades, including disposal into outer space there is still no solution for what to do with the nuclear waste. Most of the current proposed solutions for dealing with nuclear waste involve burying it beneath the earth's surface in special concrete storage containers strong enough to stop the radioactive material from escaping. Uranium is a radioactive element. It decays into a series of other radioactive elements, known as ââ¬Å"daughter productsâ⬠until it ends up as a stable form of lead. As a consequence of the various radioactive forms uranium goes through, the uranium ore deposits contain many radioactive elements, some of which are particularly hazardous. One of the major dangers of uranium is that it produces radium toxins and radon gas. Radon gas, even when inhaled in small amounts, is known to cause lung cancer. Radium toxins can find its way into people through food and water and is known to cause other types of cancer. There are approximately 60 tire waste sites in Ontario alone. Eleven of these sites contain more than 100 000 tires, and the other 49 maintain approximately 5,000 tires. On February 12, 1990, a tire dump located near Hagersville, Ontario, which contained an estimated 14 million used tires, was set on fire and burned for 17 days. The toxic smoke alone caused thousands of people to evacuate their homes. It was estimated that 600,000 litres of oil was produced by the melting tires and collected by the cleanup crews. There is the possibility that even more oil and other contaminants from the water runoff may have entered local water sources. Statistics compiled bu the United States government reports that there are as many tires in American waste sights as there are American citizens. This estimate added to an already over-burdened environment, means that the number of scrap tires on the ground in 1994 at just under a billion in the United States alone. It is important to note that warm weather areas produce more scrap tires on average than northern, cold weather climates. Considering the unlikelihood of the invention of a ââ¬Å"non-wearâ⬠tire in the foreseeable future, it would stand to reason that the supply of scrap tires will continue to rise for many years to come. The annual number of tires that are scrapped world wide is estimated to be 1. 6 billion (see Fig 1). The next decade alone will show an increase of more then 500 million tires per year. Improper disposal of tires can affect our health, our environment, and our waste management costs. Proper waste tire management eliminates whole tires from being buried in landfills, eliminates tire stockpiles that trap water, eliminates ideal habitats for disease carrying mosquitos and rodents; reduces the risk of uncontrollable tire fires and related hazards and provides raw material for scrap tire markets. Waste tires can be recycled as whole or split tires or as crumb (ground) rubber. Whole tires can be used as parts of playground equipment. Split tire uses include floor mats, belts and dock bumpers. Crumb rubber is the fastest growing market for scrap tires. Crumb rubber uses include rubber and plastic products such as floor mats, carpet, shoe soles, padding, athletic surfaces, alternative-energy fuel, and rubberized asphalt. Adding rubber to asphalt greatly enhances the material's temperature resistance and longevity (see Fig 2). Chlorine is found in nature mainly in the form of salt, a stable compound which is essential to many natural processes. Such as using massive amounts of electricity, the chemical industry destroys the salt compound's stability creating an extremely reactive form of chlorine that is not widely found in nature. The use of chlorine results in products and wastes, many of which are toxic to wildlife, humans and the ecosystem. Chlorofluorocarbons and hydro chlorofluorocarbons: The ozone layer which is located in the Earth's stratosphere is comprised of a blanket of ozone molecules. It is the primary protective shield that the Earth has against the deadly ultraviolet rays of the sun. During the past 60 years, the ozone layer has been severely damaged by millions of tonnes of ozone depleting substances (ODS) most notably chlorofluorocarbons (CFCS), have been released into the atmosphere by humans causing the ozone's deterioration. Other ODS include hydro chlorofluorocarbons (HCFCs) which is used as part of warfare also depletes the ozone layer. ODS are known to be stable substances and can survive in the atmosphere for many years. They are carried up to the stratosphere by air currents where they eventually disintegrate under ultraviolet light. This disintegration releases chlorine or bromine molecules which creates a chemical chain reaction leading to the large scale destruction of the ozone molecules (see Fig 3). A decrease in the number of ozone molecules in the stratosphere reduces the atmosphere's ability to absorb UV-B radiation before it reaches the Earth's surface. Small changes in the thickness of the atmospheric ozone layer allow significant increases in the amount of UV-B radiation that filters through which can profoundly impact life on this planet. This added UV-B radiation impacts on the stability of the global ecosystem; the genetic health of life, the quality of the air we breathe and the weather. Unless these toxic emissions are halted immediately, the ozone's depletion and damage to the global biosphere could reach severe life threatening levels leading to the end of life as we know today. PVC's are now the single largest user of chlorine and its production is growing worldwide. Wastes from PVC production contain dioxins and other highly toxic contaminants; a range of toxic chemicals is incorporated within PVC products; and burning PVC plastic in incinerators or in accidental fires creates dioxins. PVC's have become a significant source of the planet's dioxin levels. PVC's are used as a component in consumer products such as credit cards, records, toys, window frames, doors, walls, panelling, pipes and gutters; around the home in vinyl flooring, vinyl wallpapers, venation blinds, shower curtains, office furniture, binders, folders, and pens. It is also used in the car industry, as medical disposables in hospitals, in cable and wire insulation, for imitation leathers, and in garden furniture. PVC's have become part of our everyday lives (see Fig 4). The disposal of PVC's creates environmental problems. If burned, PVC products will release an acidic gas and dioxins. PVC products are a significant source of dioxins globally. PVC's eventually releases toxins which can then threaten groundwater supplies if disposed of in landfills. PVC's are not a natural material and is not bio-degrade able. PCB's are produced in several countries and are widely used in industries as heat transfer fluids. PCB's are so versatile and so widely used because of their physical properties. These properties include resistance to acids and bases, compatibility to organic material, resistance to oxidation and reduction, electrical insulation properties, thermal stability and is nonflammable. However, widespread use and improper disposal practices have led to significant environmental contamination by these commercial PCB formulations. PCB's are highly stable in the environment. Non-Industrial sites have also been reported with high contamination (i. e. , The Antarctic). PCB's are usually found in fish, wildlife, and human adipose tissue, blood and milk. Health affects for babies who suckle their mother who has a high concentration of PCB's in their milk (see Fig 5). Between the 1940's through to the 1970's PCB's were used to coat silos of barns. The coating however, leaked from the walls into the cattle and into the human food chain via milk and meat. An increase in cancer diagnosis is humans has been reported by families that lived or used to live near these silos. These silos are now being dismantled or destroyed due to these findings. A case of Yusho/Yu-Cheng poisoning occurred in southwest Japan where 1600 individuals fell ill after eating rice oil contaminated with a commercial PCB industrial fluid. Nineteen hundred individuals also fell ill after eating the same thing. This incident occurred at the same time and area. Sixty-four percent of the victims made a recovery however, some reported to get headaches, and stomachaches, numbness of the extremities, coughing and bronchial disorders, as well as joint pains in many of the victims. Children that were affected by this incident had related growth and abnormal tooth development, and newborns exhibited systemic pigmentation and were born undersized. Beginning in 1980, congressional appropriations to a ââ¬Å"Superfundâ⬠ââ¬â money to be used by the EPA for hazardous waste cleanup ââ¬â have totalled $8. 4 billion, of which the EPA has spent $6 billion (1990), and has completed work on only 52 sites listed on a national priority list of 1,218 sites that urgently required Superfund cleanup. There is no safe way to dispose of the toxic chemicals produced by industrial plants for everyday life. If there is, it can cost millions or even billions of dollars to companies and governments around the world. There are so many different toxins today that are affecting the way we live. The effects of these chemicals are destroying the environment and causing illnesses and even death in many people. Toxic chemicals must be properly used as we enter the new millennium to allow the production of toxic chemicals world wide should be cut to levels where it is considered safer for the environment and prevent increases in future levels. This global cut back should remain in place until technologies are created to safely dispose of the toxins safely. The planet. Humans must give the planet time to dissolve itself of the current toxins within the environment and repair itself to the point where living conditions are safe and clear of chemical hazards.
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