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Information

What is Dioxin

Dioxin is a general term given to a large group of very toxic chemical, that get created as a byproduct during the manufacturing or burning of organic chemicals and plastics that contain chlorine. "The most toxic of these chemicals is 2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD". [Dioxin Homepage] The potency of all other Dioxin like chemicals are measured against this substance.

Where it comes from

The process required to create Dioxin is rather simple, all that is needed are three common ingredient. The first is a material containing a sample of Chlorine. Chlorine is a widely used chemical that can be found in thousands of products ranging from bleaches, plastic, and personal hygiene product. The second ingredient is an organic substance such as wood, pulp or paper. And the third ingredient is a catalyst such as fire that creates the chemical reaction during which Dioxin is formed. The EPA (Environment Protection Agency), has identified incinerator and other combustion sources as being the largest emitters of Dioxin. These sources, including medical, garbage, and military incinerators account for over 90% of all Dioxin emissions. Another major source of Dioxin contamination is produced by pulp and paper manufacturers, which account for 7% of Dioxin emissions. However, a small percentage of Dioxin emissions remains unidentified, it is believed that this source includes accidental or natural sources such as house fires, cars and torches.

The following chart shows some of the main sources responsible for Dioxin production
Chart taken from [Toxic Report, April 2002]
 
TABLE 4: Dioxin Sources in the U.S.
  % of total identified emissions
Sources: U.S. EPA(1) Cohen(2) Thomas (3)
Medical waste incinerators 45 48.7 10
Trash and apartment incinerators 42 20.1 65
Haz. waste incinerators/Cement kilns 4* 8 2.5
Pulp mills 3 ND 0.1
Wood burning 3 1.9 5.8
Copper recycling 2 4.2 2.5
Forest fires/Agricultural burning 0.7 ND 7.5**
Vehicle fuels 0.7 1.4 0.7
Sewage sludge incineration 0.2 0.6 1
Dioxin-contaminated chemicals <1 ND 4.5
Lead recycling <0.1 ND ND
Steel smelters ND 10.6 0.8
Open waste burning ND ND 2.5
Accidental fires ND ND 0.7**


What is Chlorine

Chlorine is an essential ingredient required in the creating on Dioxin. Basically this substance is a natural element which constitute for a large percentage of the earths surface. Chlorine is a very reactive chemical, because itís surface is missing as electron, it is constantly attracted to other molecules. This trait makes Chlorine very useful in chemical reaction which can change, build or improve various products. Most often chlorine is found attached to other elements, to make it useful for manufacturing it must first be separated. The process that is used to separate chlorine from other substances is called electrolysis. This process involves passing large currents of electricity thought sea water, which removes the negative chloride ions and deposits them on the positive sodium. The product is chlorine gas, which will be chilled pressurized and made in to a powder.

Incineration

Incinerators and other combustion facilities were proven to be the single largest source of Dioxin contamination. Basically, an incinerator is an oven that uses extreme temperatures to reduce large quantities of matter into ash. In most cases, incinerators are used to dispose of organic garbage. By doing so, it is possible to reduce the amount of property required for landfills, as well as save money associated with the removal of waste. However incinerators are also widely used for the purpose of destroying medical and industrial waste. Medical and other toxic garbage cannot be frown away. Due to a threat of contamination, all waste from these sources must be destroyed. Medical and industrial incineration accounts for the largest percentage of dioxin production. This fact can mainly be attributed to the large quantities of PVC plastic (more on this later) which they use. Many attempts have bean made to reduce the amount of Dioxin that is being released by these sources. The most widely used method is a filter that remove the ash from the exhausts. Although this method has proven somewhat effective, it still does not terminate all the dioxin emissions. The main problem is that the Fly ash, the material that Dioxin travels in, is very small. Even with the use of filters, it is virtually impossible to stop all of it from leaving the facility. Another problem is the waste created by the incinerator. The remains of the burnt material created by the incinerator are heavily contaminated with Dioxin. There is no other way to dispose of it, but to through it away. The third problem is that filters are only used in larger facilities, leaving the majority of the smallest once uncontrolled.

Materials

One of the largest factors in the production of Dioxin can be attributed to polyvinyl chloride plastic or (PVC) for short. According to the studies made by the EPA, this product has bean directly linked to over 40% or all Dioxin productions. So why does PVC play such an important role in the creation of Dioxin? The first reason why PVC is such a major source of dioxin, is simple the popularity of itís use. PVC can be found virtually anywhere, in fact over 80% of all chorine goes in to the manufacturing of this product. The second factor is itís growing demand. Unlike other chlorine products whoís numbers have bean decreasing steadily, the demand for PVC in on the rise.

The following chart depicts the increasing demand for PVC



Why itís so harmful

One of the traits that make Dioxin so harmful is itís similarity to natural hormones (chemicals used the body to transmit information). Like hormones, Dioxin has the ability to pass thought a cellís membrane and attach itself to the neural receptors (parts of the cell that collect information). By doing so, a dioxin molecule can literally alter the genetic structure of the cell, creating new instructions that can interfere and disrupt the immune and neurological systems. Another factor that makes Dioxin so harmful is itís ability to remain in our bodies for such long periods of time. Because the immune system has no deface against this pathogen, there is basically no way to remove it. Unlike most other toxins, dioxin does not require a minimal dose to be harmful. Once itís inside the body, even the smallest amounts of Dioxin can begin to disrupt itís functions. So how does Dioxin get into a human host? Dioxin is whatís called a hydrophobic substance, basically meaning that it tries to avoid water. Then ash from an incineration facility, lands on water or soil, the dioxin contained within is automatically drown to the fat in living creates. Because of itís long life span, dioxin can travel from one host to another thought the ecological food chain until it finally accumulates inside higher life forms. It was found that the levels of Dioxin in fish were often 100,000-million times that of surrounding water. Sense humans are at the top of the food chain, most of the dioxin from the environment eventually ends up in our diets. There are many other sources that were found to be contaminated with dioxin. It is assumed that most products that involve the use of chorine it their manufacturing can contain small traces of the toxin. Objects such as cleaners, toys and clothing.



Life cycle

The life-span of Dioxin is directly related to the amount of sun light to which it is exposed. If left in the open, the Half-life (the time it takes for the substance to degrade to Ĺ itís size) is believed to be only 20 hours. However, in most instances dioxin finds refuge in near by water systems, or soil that can significantly increase itís life. If released in to the water, dioxin will usually find itís way into sediments or suspended materials. Under such conditions dioxinís half-life has been estimated to excess 1.5 years. In surface soil dioxinís half-life is believed to be between 1-3 years, and over 12 years deeper down. The life-span of Dioxin also depends on the climate. Because of the higher amounts of sunlight founds in hot climates, Dioxin does not last very long. However in cold, or frozen climates Dioxin can remain hidden away for centuries.