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    23-Feb-2016
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Pesticides. Good or Bad ?. By Syed Haider 9M. - PowerPoint PPT Presentation

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Good or Bad ?PesticidesBy Syed Haider 9M

Pesticides are basically chemicals that are sprayed on plants and crops to kill any insects that my eat them. By killing off the pests living in the area of the plant the plant has less competition and can get more nutrients and sunlight. This means that the plant grows bigger and is stronger. This another reason why farmers like to use pesticides on plants. But the main reason is to stop the pests from ruining the plant. Herbicides also kill plants like Weeds from growing which also reduce the amount of competition a plant gets so farmers also use that on their crop lands. Spraying methods

Pesticides are used in developing nations like Africa to save lives. The majority of deaths in Africa are caused by malaria. The people of Africa used the DDT pesticide to kill of malaria carrying mosquitoes. This has saved many lives in Africa as it has been sprayed on mosquito breeding grounds.

Pesticides are not just used in fields and farms, They are also used in your homes. Insecticides (another name for pesticides) are in your homes in the form of insect killing sprays. Companies like Baygon and Pif Paf are also pesticides because they kill pests.

Algae Water Flea Stickleback Kingfisher Peregrine Falcon Pesticides are also very dangerous to humans and to other organisms that do not harm plants. For example in 1940 1950 people decided to use a pesticide called DDT to protect algae from water fleas. During that time the number of peregrine falcons fell dramatically. It was later discovered why? Research showed that The Falcons got DDT by eating King fishers that had it and they got it from further down the food chain. The DDT in the falcons made their egg shells really thin so they broke when they were incubated. It is impossible to stop it from getting them into food chains even when you are careful.

There were also other pesticides that caused havoc like DDT did, one of them was Dieldrin that killed pigeons and foxes too. It also happened in the same way. But there are other problems too like overuse of pesticides. As I have said earlier about the malaria infected mosquitoes if you use DDT too often on them a new mosquito can take place and that mosquito becomes DDT proof. This causes his offspring to be resistant to DDT too. There are other problems like water contamination from off running and aquatic life in danger but the main issue is that it can be harmful to us humans too.

If you look on the back of a pesticide it usually says do not breathe in or something about dont spray on hand. Scientists say that if pesticides got in to our food chain they would probably kill us too. But on the other hand it also has saved many lives in countries. So you can not say if it is good or bad it is both. The best solution is to make a pesticide that kills the intended target only.