Pesticides and their environmental impact Essay

Introduction Pesticides are chemicals or organic substances that have been designed to prevent pests, weeds or diseases in agricultural production and other places where public health is of paramount importance. Pesticides are very important in agricultural production because they control vermin that would otherwise lead production losses during growth and the storage. (Hond, Frank et.al.2003). Various researches have continued to indicate that farmers stand to loose about a third of the crop field if pesticides are not used as a control measure. This would have catastrophic effect on food security across the globe. Thus pesticides play a major role in food production. However the handling and the usage of the pesticides has continued to have long lasting effect on the environment including the flora and fauna. (Hamilton D & Crossley S   2004). Since 2500 BC farmers used biological means to control various pests. It was the safest method even though not the most effective. The farm products treated by biological pesticides  Ã‚   did not have any side effects to the consumers who used these products. However after the agrarian revolution, an increasing number of farmers started using artificial pesticides that were more suitable for the increased scale of agricultural production. (Hond, Frank et.al.2003).   There are different types of pesticides depending on the target pests; insecticides help to control insects, bactericide control bacteria and fungicides control fungi. We also have synthetic pesticides that are artificially produced in factories. DDT is always listed as one of the most effective pesticides yet the most environmental destructive which led to its eventual ban in 1939 in over 98 countries. (Hond, Frank et.al.2003). Environmental Effects The environment is always contaminated when pesticides are applied on crops. During the process of application it has been known that some amounts of pesticides vaporize and are later deposited in the soil or other waterways by rainfall. (Hamilton D & Crossley S   2004). Pesticides present in ground water or drinking water has great impact and is both costly and problematic to control. For example the total concentration of pesticide residues in many ground water supplies in the EU countries exceeds the maximum permissible concentration. In the US the situation is the same and research done on about 68,000 wells revealed that about 9,000 of these wells were indeed contaminated with the residues, which exceeded the Environmental Protection Agency standards (EPA) for water meant for drinking. (Hond, Frank et.al.2003) Contaminated water is very harmful to animals, vital microorganisms in the soil, and extremely dangerous for the marine ecosystem. (Hond, Frank et.al.2003) Pesticides and Wildlife Wildlife by nature do not discriminate in their eating and drinking habits, thus when the pesticides residues find their way to the areas where the wildlife is bound to exist then it poses great danger as they may lead to a slow but sure death of the animals. A very good example is the death of flamingoes and other bird species in the Kenyan lake Nakuru. These deaths were as a result of the excessive use of pesticides in the upstream waterway that feed the lake with water. (Watson, D 2004).   Greater effects have also been recorded amongst various bee and bird species that are very important in the pollination processes. A good example of this effect was also recorded in the US and Europe between 1950 and 1970 when the dramatic decline in the population of the birds of prey was attributed to the organochlorine pesticide that was POPs. The use of DDT was found to break down to DDE, chemical that was responsible for the cause of eggshell thinning that resulted to the crushing of the eggs leading to the failure of the breeding cycle of the birds of prey that also included the fish-eating birds. http://www.greenpeace.org/china/en/campaigns/food-and-agriculture/pesticides/ Another pesticide aspect that has led to the decline in the bird populations is when they have reduced the existence of certain weeds in various arable fields. The weeds play a very significant role in providing the birds with seeds and insects for food, thus when they are decimated then it affects the bird’s food chain. The great decline of the grey partridge is directly attributed to the use of herbicides that change the availability of the food supply.  Ã‚   http://www.greenpeace.org/china/en/campaigns/food-and-agriculture/pesticides/ Until recently a synthetic pyrethroid insecticide called cypermethrin was commonly used in sheep dips across the UK and had adverse effect on the environment. The greatest impact was realized in the marine life where a vast number of various aquatic invertebrates were killed. http://www.greenpeace.org/china/en/campaigns/food-and-agriculture/pesticides/ In fish the residues are consumed resulting to the bioaccumulation of the pesticides in the birds of prey that eat this fish. Such pesticides as dieldrin   and aldrin were directly blamed for the decline in the deaths and population decline of birds of prey. However it is worth noting that in areas where the usage of the chemicals is prohibited the population of the birds species has recorded remarkable increase. http://www.greenpeace.org/china/en/campaigns/food-and-agriculture/pesticides/ Health Effects Workers in the manufacturing companies are at great dangers of developing various other complications while handling the manufacturing processes. Sometimes the workers lack adequate protection and are therefore exposed to the chemicals that are highly carcinogenic. Farmers and other pesticide handlers are the most exposed people to the dangers of the pesticides. (Watson, D 2004). Organophosphates are less harmful to the environment  Ã‚   compared to organ chlorine pesticides. The pesticides can cause abdominal pain, headache, dizziness, nausea, as well as skin and eye problems. When pesticides are used for a long time they can also cause respiratory problems, memory disorder, cancer, neurological deficit and in women who are exposed so much to the pesticides it can cause miscarriages and birth defects when pregnant. (Walter A. et.al.2005) Consumers Most of the crops planted by big scale farmers are very harmful to the consumers because these farmers use the pesticides for cultivation processes. Fruits and vegetables contain the pesticides residues making them harmful to the consumers. Due to these residues, the maximum Residue limits has recommended some standards for individual pesticides food to be used. The EPA has set tolerances that detect the toxicity of the residues and amount of pesticide application that remain in food before it is marketed and prepared. The tolerance level is obtained using scientific assessments that manufactures are required to produce before a particular pesticide can be registered. (Walter A. et.al.2005) The study published in 1993 showed that the infants and children are exposed to pesticides through their diet, while in the US the study shows that pesticide residues in food cause causes of cancer. (Watson, D 2004). The pesticide residue has been a major concern in the US making it possible in 1996 to begin a program known as United States Department of Agriculture to allow its food to be tested for different types of pesticides. The program allowed the test of different vegetables and fruits commonly eaten for example: Apple, Lettuce, Pears and Oranges. To avoid the entire health problem, the consumer can wash, peel, cook and even trim the fat from meat and eat variety of food to avoid long-term exposure to pesticide. The consumer is also advised to buy organic food. (Walter A. et.al.2005) Pesticides are generally exposed to the general public some of the pesticides are very harmful and because they lack proper handling instructions pose great dangers not only to the users but also to the public at large. According to various studies, various pesticides have severe effects on young children and cause leukemia. Organophosphate can cause infliction to the nerve cells and may lead to low birth weights. This is because when pregnant women are exposed to the pesticides they have a very high chance of affecting the uterus and the child carried in the womb. (Walter A. et.al.2005)   With the development of new technology most pesticides are becoming obsolete and other better methods are being used as form of pest control such technologies are being developed in such countries as Bangladesh, Indonesia and Mexico. To reduce health and environmental risks, biological and botanical methods are being  Ã‚   developed and applicators are advised to adopt other methods other than the use of chemical pesticides. For example farming methods like polyculture where by you grow multiple types of plants or even planting crops where the pests that damage the plants do not exist (crop rotation) if not you can adopt the US style of spraying the pests with hot water or the release of natural predators. Interfering with insect’s production can be accomplished by sterilizing males so that there is no production of the off springs. All this methods have been achieved in Indonesia and Sweden thus making their environment very friendly not only to human beings but also to their crops and animals. (Hond, Frank et.al.2003). Conclusion Pesticides have been of great use especially in the production of food to sustain the ever-increasing world population. Most of the pesticides have significant side effects on the environment and have continued to cause untold damage to the ecosystem. In the developed world the governments have continued to institute very strict measures that have seen the banning of the usage most of such products. The producers realizing the challenges they face in these regions have opted to switch their operations to the third world countries where the regimes lack the necessary infrastructure or legislation to control the use of the said products. Thus the dangers have been shifted from the first worlds to the poor third world countries, which are left to bear the brunt of the pesticides. First world countries have the responsibility of protecting the world from the effects of the pesticides because they are the largest producers.    Work cited Hamilton, Denis; Crossley, Stephen (2004). Pesticide residues in food and drinking water. J. Wiley. Hond, Frank et.al. (2003). Pesticides: problems, improvements, alternatives. Blackwell Science. Pesticides-and-the-environment: Retrieved on 11th April from http://www.greenpeace.org/china/en/campaigns/food-and-agriculture/pesticides/ Walter A. Alarcon, et.al. (2005) Pesticides and the Environment. â€Å"Acute Illnesses Associated With Pesticide Exposure at Schools†. Journal of the American Medical Association Watson, David H. (2004). Pesticide, veterinary and other in food residues: woodhead Publishing