advantages and disadvantages
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Thimerosal is often has been the preservative of choice in vaccines since the 1930s due to its low cost and high effectiveness in killing bacteria. However, While it may be cheaper to manufacture vaccines that contain thimerosal, it is important to note that thimerosal itself can prove to be very toxic.
Not only can thimerosal be injected or ingested, but it can also be absorbed through the skin on contact. It is toxic and can alter genetic material, create numbness in the extremities, cause birth-defects, increase infant mortalities, and destroy lung tissue. Thimerosal also shares some symptoms of mercury poisoning, such as changes in the nervous system, and narrowing of the visual field. There has also been evidence to show that Thimerosal causes neurdeveloptmenatl disorders, especially autism, in children. As seen in the 'mechanisms' section of this website, mercury in the body stimulates production of metallothionein. Ethylmercury, being a bioaccumulative compound, tends to initiate high production levels of matllothionein in the body. However, in early stages of life, such high levels of metalliothionein in the body, can cause the brain to develop abornormally, and many woman who have taken thimerosal containing shots prior to or during pregnancy have given birth to autustic children. The Food and Drug Administration (FDA) Modernization Act of 1997 eventually called for a review and risk assessment of all mercury-containing food and drugs. Vaccine manufacturers responded to FDA requests for December 1998 and April 1999 to provide detailed information about the thimerosal content of their preparations. From the early 1970s until present day, the number of vaccines regularly received by children in the US before the age of four has risen from two or three to up to twenty-two. There is concern on both sides of the debate in regards to motivating factors. Those who denounce thimerosal suspect that government agencies and pharmaceutical companies are denying a connection for fear of financial liability and the creation of mistrust in vaccinations. Those who deny a connection between thimerosal and neurological disorders have charged thimerosal's critics as being medically and scientifically unqualified, emotionally distraught, or interested in pursuing litigation. While many vaccine manufacturers have either reduced the amount of thimerosal in their vaccines, or removed it altogether, there is still much debate on how valid the claims against thimerosal are, and how dangerous it really is in the amounts that are allocated per innoculation. For a table of of the most commonly used vaccines and their thimerosal contents, click here (same server).
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