Friday, October 18, 2019
The affects of Agent orange Research Paper Example | Topics and Well Written Essays - 1750 words
The affects of Agent orange - Research Paper Example Talking about the chemical composition of the Agent Orange, it is a 50:50 mixture of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2,4-dichlorophenoxyacetic acid (2,4-D) (Scheme 1). Scheme 1: Phoxyacetic acids that form Agent Orange (Claus and Walters, 148). Series of studies were undertaken in order to evaluate potential effects of Agent Orange and its production by-products on health. Let alone the mixture that form Agent Orange, 2,4,5-T is highly toxic and there is a substantial amount of evidence regarding its possible effects on health and environment. In late 1960s it was revealed that 2,4,5-T usually contained dioxin (TCDD), which was more toxic then 2,4,5-T. This information allowed to explain a number of properties attributed to Agent Orange. Scheme 2: Production of Agent Orange components and unwanted side reactions (Claus and Walters, 148). 2,4,5-T was synthesized by Robert Pokorny in 1941. Subsequently the compound was extensively studied and patented as a weed killer. Later, the spectrum of its applications increased as well as the amount of publications and patents regarding this product. 2,4,5-T was in production from 1950 to 1979. During that time Dow Chemical was the largest company producing this chemical for agricultural purposes. Taking the production from the lab into industry led to the formation of the highly toxic dioxin 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as a consequence of a side reaction (Scheme 1). The first step of the process is the reaction between 1,2,4,5-tetrachlorobenzene and sodium hydroxide to afford 2,4,5-trichlorophenoxide (2,4,5-TCP)(Scheme 1). The formed product would then react with chloroacetic acid at 1400C to yield 2,4,5-T. Temperature control is critical for both processes, because at 1600C 2,4,5-T can participate in a self-condensation reaction leading to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)(Heaton 1996). In the second half of the 20th century no precautions were taken to eliminate the formation of t his dioxin. As a result, seventeen thousand people were exposed to this dangerous by product in Italy during an accident on a chemical plant near Seveso in 1976 (Eskenazi, et al., 2003). When such precautions were taken it was difficult to maintain the required temperature in the industrial scale reaction vessel. For this reason dioxin was a consistent by product in the 2,4,5-T production. Its quantities were measured in parts per million, and according to initial legislation had to be no higher than one part per million. Later the limit was pushed to 0.1 ppm and 0.01 ppm in the United States and UK respectively. In order to meet this requirement better temperature control was introduced and the formed dioxin was removed from 2,4,5-T (Hay 160). Talking about toxicology of dioxin and the components that form Agent Orange, according to Arthur Galstonââ¬â¢s extensive review published in 1979, TCDD in trace quantities was able to bring up serious health issues in test animals. Dioxin e is the primary toxic compound of Agent Orange. Its presence was able to promote chronic lymphocytic leukemia (CLL), soft-tissue sarcoma and both Hodgkinââ¬â¢s and non-Hodgkinââ¬â¢s types of lymphoma. Exposure to Agent Orange leads to increased chances of acute myelogenous leukemia in the children of the US soldiers who served in Vietnam (Schuck 19). Another study, conducted in 1969 exposed the toxicity of
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