Friday, June 11, 2010

my paper on pesticides.

“Organic pesticides are compounds derived from plants, shrubs, and herbs.”1

What is the big deal about organic pesticides? We have all heard about the good things. Traditional pesticides are bad for the environment and for you. They hurt people. They can poison kids and pets. I thought that it would be interesting to find out some of the pros and cons of both organic pesticides, and traditional ones as well. In this report/essay, organic pesticides are ones that are derived from plants or living organisms.

Traditional pesticides do have some benefits, despite the general ill-feeling generated towards them. For one, they act quicker. Some organic pesticides can take up to several weeks to take noticeable effect, which can cause some problems if you need the bugs/plants/fungi out as soon as possible. They are also more effective in some areas. People know they are going to work. Sometimes the organic pesticides don't work on certain types of animals or plants. Since the traditional methods have toxic chemicals in them, they are a lot surer method of killing something off. The other obvious benefit is that they are a lot cheaper when being used in large quantities. It just costs a heck of a lot more to buy several fields worth of organic pesticides then it does to buy the ones filled with chemicals.

Organic pesticides have some good points though, too. For one, they are a lot softer on the good plant and animal populations. What is left behind is usually not nearly as bad for animals and humans as the stuff left over by traditional pesticides. They don't contaminate water as much as traditional methods do, either. They are altogether better for the environment. Besides the “green” benefits, Organic pesticides can be better for humans. “ 'The benefits are numerous,' he said. 'Organic and natural elements traditionally break down extremely fast. Therefore, the treatment does not harm you. Would you want something around your home that is part of your daily allowance? Or would you rather have something in your body

that is part of your metabolism? Or do you want a chemical that your liver and kidneys have to break down? That is how people get sick from cancers.'”2 Besides the health benefits, the organic pesticides can just be gentler on the plants that people are trying to grow.

For some of the categories of pesticides, traditional can be better, and for other the organic can be better.

Herbicides are pesticides that either kill or discourage plants to grow in certain places. Although there are organic alternatives, the traditional chemical type is still used virtually everywhere, because of it's low price and high-toxicity to plants. “Organic herbicides are expensive and may not be affordable for commercial production. They are much less effective than synthetic herbicides and are generally used along with cultural and mechanical weed control practices.”3 Although the traditional types are very effective, there are very serious drawbacks. For one, there is evidence that herbicides can lead to very serious sicknesses in humans, including Parkinson's disease. Herbicides can also cause negative impacts on the ecology. “In addition, some important environmental effects are associated with the use of herbicides. These include unintended damage occurring both on the sprayed site, and offsite. For example, by changing the vegetation of treated sites, herbicide use also changes the habitat of animals such as mammals and birds. This is especially true of herbicides use in forestry...In addition, not all of the herbicide sprayed by a tractor or aircraft deposits onto the intended spray area. Often there is drift of herbicide beyond the intended spray site, and unintended, offsite damages may be caused to vegetation. There are also concerns about the toxicity of some herbicides, which may affect people using these chemicals during the course of their occupation (i.e., when spraying pesticides), people indirectly exposed through drift or residues on food, and wildlife.”4

Herbicides, however, are not the only type of pesticide. Fungicides are used to prevent plant diseases while they are growing, and to protect food and plants after harvesting. Many types of fungi is deadly to plants, so it is crucial to farmers that they prevent it. Not very many fungicides have an immediate impact on humans or animals, but when someone eats food that still has fungicide on it for a prolonged period of time, there can be drastic health effects on the human. Many fungicides are toxic if someone has prolonged contact with them as well, but there aren't very many of these. Another story, however, is the impact that they can have on the environment. “Fungicides are very harmful to the ecosystem and can contaminate many water bodies.”5 A lot of fungicides either get absorbed into the plants, or drift into water bodies. If something eats the plant, or drinks the water, it can be quite toxic to the animal.

The most widely thought of pesticide is called an insecticide. Insecticides are pesticides that are used to kill (or at least discourage) bugs. “Nearly all insecticides have the potential to significantly alter ecosystems; many are toxic to humans; and others are concentrated in the food chain.”6 Since traditional insecticides are used for killing a wide range of pests all at once, they can be dangerous for the populations of the wanted insects. For example: An insecticide might be aimed at trying to kill aphids, a pest that can severely damage a plant. It might also get rid of the ladybug population, however. “Despite their many advantages, conventional insecticides are not ideal pest control agents. Indeed, one of their greatest strengths, broad-spectrum activity, is also one of their greatest weaknesses. While it is certainly an advantage to control multiple pest species with a single chemical treatment, the non-specificity of most conventional insecticides poses a serious threat to non-target organisms in the environment. High mortality among natural enemies can have an enduring impact on the ecological balance of any community. In the absence of biocontrol agents, more insecticide applications may be the only recourse available to stop pest resurgence. Once we step onto this "insecticide treadmill", it can be very difficult to get off.”78 Organic insecticides are often better for both the people and the environment, because their bases are made from natural carbon, instead of chemicals. Traditional insecticides can also have unfortunate effects on humans. “Over the last fifty years many human illnesses and deaths have occurred as a result of exposure to pesticides, with up to 20,000 deaths reported annually. Some of these are suicides, but most involve some form of accidental exposure to pesticides, particularly among farmers and spray operators in developing countries, who are careless in handling pesticides or wear insufficient protective clothing and equipment. Moreover, there have been major accidents involving pesticides that have led to the death or illness of many thousands.”

Although it would seem that organic pesticides are the best choice, there are alternatives even to them. Biological pest control is a method of getting rid of pests by using their natural predators. “Predator insects are bred commercially for such use and have proved extremely beneficial in pest control. These mostly carnivorous insects do not attack vegetation and being extremely voracious consume bugs on a massive scale daily.”9 Biological pest control has cons. For one, it costs more because if the predators leave, then the person using the pest control has to buy or breed more. Some types of biological pest control uses diseases to kill weeds and unwanted bugs. These are mostly specific, but if something goes wrong it could kill some of the wanted plants and animals. If it works correctly, however, biological pest control can be very good for the environment and a lot less risky for workers. Because it employs the natural predators of pests, it is assured that they won't develop an immunity as they might with traditional or even organic pesticides. They don't have a negative impact on the environment, since they aren't spraying anything into the air, and if any bugs fall into the water... well, you have a dead bug. And they don't have any effect on humans (except for the wasps, who might possibly sting someone, or bugs that might bite) which makes them a safer alternative to the pesticides that are currently being used, even if they are organic.

Organic pesticides have some good things about them, such as being friendlier to the environment and to humans, and some bad things about them, like acting slower, and being more expensive. Biological pest controls have some negative things as well, such as being more expensive and possibly dangerous if they get out of hand, and some good things as well. I have come to the conclusion that in certain circumstances, traditional pesticides are alright, but it is better to use either biological pest control or organic alternatives as much as possible.

1Sarah Ince;;

2Mark Ruben;;



8Pollution issues;;;

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