Effects of Pesticide Case Study

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Effects of Pesticide Case Study
INTRODUCTION

The Bago City is the rice granary of Negros Occidental. The farmers of Bago City are struggling because of the pest. They have decreased their production of rice because of the pest. Our goal of engaging this case study is to analyze and see the effect of the pesticide to the crops. We are to seek good and bad effects of these pesticides. We’re going to focus only on finding the effects of these pesticides so we can come up with a good report. By observing and surveying, where going to come up with a finding to know the possible effects of pesticide.

FINDING

Regulation of Pesticides
Pesticides are tested and approved for use by the Environmental Protection Agency (EPA), which establishes "tolerances," or maximum residue levels, that limit the amount of a given pesticide that can safely remain in or on a food. The Food and Drug Administration (FDA) is then responsible for monitoring pesticide levels on fruits and vegetables, while the Department of Agriculture (USDA) is charged with the task of surveying pesticide residues in meat, eggs and dairy products.  Many believe that the EPA's methods for testing pesticides are insufficient because they only examine the effects of exposure to pesticides at high doses. Without conducting research concerning long-term exposure to low doses of pesticides, these studies neglect to base safety levels on real-life situations. Moreover, the tests examine the effects of a single chemical, whereas people are typically contaminated with small amounts of hundreds of pesticides at any one time. The FDA is also criticized for its inadequate monitoring of pesticide levels on fruits and vegetables.

Effect on plants
Nitrogen fixation, which is required for the growth of higher plants, is hindered by pesticides in soil. The insecticides DDT, methyl parathion, and especially pentachlorophenol have been shown to interfere with legume-rhizobium chemical signaling. Reduction of these symbiotic chemical signaling results in reduced nitrogen fixation and thus reduced crop yields. Root nodule formation in these plants saves the world economy $10 billion in synthetic nitrogen fertilizer every year. The effects of rice plants treated with various pesticides on feeding, survival rates and population growth susceptibility of the treated rice plants and amounts of free amino acids and sucrose were studied. Experiments indicated that the effects of the tested pesticides were dependent on nymph’s age, pesticide and their dose and time after application.

Effects on soil

Many of the chemicals used in pesticides are persistent soil contaminants, whose impact may endure for decades and adversely affect soil conservation. The use of pesticides decreases the general biodiversity in the soil. Not using the chemicals results in higher soil quality, with the additional effect that more organic matter in the soil allows for higher water retention. This helps increase yields for farms in drought years, when organic farms have had yields 20-40% higher than their conventional counterparts.  A smaller content of organic matter in the soil increases the amount of pesticide that will leave the area of application, because organic matter binds to and helps break down pesticides. Degradation and sorption are both factors which influence the persistence of pesticides in soil. Depending on the chemical nature of the pesticide, such processes control directly the transportation from soil to water, and in turn to air and our food. Breaking down organic substances, degradation, involves interactions among microorganisms in the soil. Sorption affects bioaccumulation of pesticides which are dependant on organic matter in the soil. Weak organic acids have been shown to be weakly absorbed by soil, because of pH and mostly acidic structure. Absorbed chemicals have been shown to be less accessible to microorganisms. Aging mechanisms are poorly understood but as residence...
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