Saturday, September 28, 2019

Analysing The Effects Of Ddt Environmental Sciences Essay

Analysing The Effects Of Ddt Environmental Sciences Essay DDT is a white, solid, crystalline powder with no taste or odor. DDT (C14H9C15) is derived from reaction between chloral and chlorobenzene in presence of fumes of sulfuric acid. DDT is insoluble in water and it is soluble in organic solvents such as, fats and oils. DDT (dichlorodiphenyltrichloroethane) is an organochlorine pesticide widely used to control mosquito and insects that carry diseases like malaria, typhus, and other harmful diseases and pest in agriculture (Martin, 2008; Raghavendra et al., 2010). DDT was banned in the U.S. in 1972 because it was identified to cause damage in birds and other wildlife, but it is still used in some developing countries (Bhuiyan et al., 2008). It is still present in environment due to current use in other countries. DDT and its breakdown products (DDE and DDD) can easily break down by sunlight, but they are very hard to dissolve in soil. DDE (dichlorodiphenyldichloroethylene) and DDD (dichlorodiphenyldichloroethane) are two major metabolites and breakdown products of DDT. DDD was also known as pesticide, but it was banned whereas DDE does not have any commercial use (Eskenazi et al., 2009). DDT was first synthesized in 1874 by Othmar Zeidler. In 1940, DDT was first used to treat Dutch elm disease. DDT was majorly used in World War II to protect troop and civilians from diseases. In 1939, Paul Mueller discovered DDT as insecticide and he won the Nobel Prize in 1948 for it. After this, people started using DDT as pesticide for their home, agriculture purpose and in gardens (Eskenazi et al., 2008). However, DDT started to cause diseases during this time and this increases public concern to Rachel Carsonà ¢Ã¢â€š ¬Ã¢â€ž ¢s Silent Spring. Rachel Carsonà ¢Ã¢â€š ¬Ã¢â€ž ¢s Silent Spring was published in 1962, which contains environmental impacts of DDT in the US (ATSDR, 2002; Eskenazi et al., 2008; Martin, 2008). DDT is strongly absorbed by soil and remains there for long period of time (Bhuiyan et al., 2008). They released f rom soil by various types of reactions such as, runoff, photolysis, aerobic and anaerobic biodegradation and volatilization (van den Berg, 2009). In surface water, DDT will bind to particles that are present in the water and sediments. DDT is taken up by small organisms and fish from the water and then bioaccumulate in organisms to higher trophic levels. DDT deposited into the adipose tissues and fats in organisms. DDT shows bioaccumulation and biomagnification as it has lypophilic property (Bhuiyan et al., 2008). In 1950s, first evidence of DDT toxicity in bald eagles, robins, osprey, pelicans, peregrine falcon, and fish-eating mammals was observed (Xiao et al., 2008; DDT: An Introduction, 1996; Martin, 2008). Objectives This paper has five objectives: (1) To discuss the sources and main causes of DDT; (2) To discuss its mechanism of action as insecticide or pesticide; (3) To discuss the health problems and toxicological effects associated with DDT; (4) To discuss the environmental impacts of DDT; (5) To discuss control measures and various methods of dealing with DDT sources and problems. DDT in the Environment DDT is not soluble in water but it can form strong bonding with soil particles. DDT is still present in environment in soils that were exposed to DDT during earlier time. DDT is a volatile so it can be transported and evaporated as a gas. DDT is not commonly found in groundwater because it is less soluble in water and it will more likely to bound with soil particles rather than water molecule (ATSDR, 2002; Walker, M., Powell, P., 2003; van den Berg, 2009).

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