Using pesticides are an economical way of controlling pests, as they require low labour input and allow large areas to be treated quickly and efficiently. It has been conservatively estimated that for every pound a farmer spends on farm chemicals he receives £4 return, which makes the use of pesticides very cost effective for the farmer, whilst the production costs and energy inputs are lower. (9) As science technology is getting even better, scientists are able to produce chemicals, which are specific for a certain pest, which means that a farmer can choose to buy a pesticide without harming species other than the targeted one. This allows more flexibility in management options and better timeliness of pest control. (9) As modern society demands nutritious food free from harmful organisms and blemishes, pesticides can ensure a plentiful supply and variety of high quality, wholesome food at a reasonable price, which means that farmers are able to produce better quality crops at a higher quantity and reasonable price. (9)
When pesticides are applied to crops, they are fast acting, and work against a specific pest and are able to control large infestations. They are also easy to obtain and apply and may increase crop production by reducing crop losses, which means that their use may appreciably improve human health as a result. (7) Quite frequently, pesticides are commonly used to prevent problems such as the spread of weeds in gardens and lawns; treatment of export and import produce to prevent the spread of pests; treatment of stored products to prevent pest attack and destruction during storage. By using these methods of preventing pests, it makes pest control very efficient as farmers would know how much to apply and how specific it would be. (9) Most certainly, pesticides have been very beneficial to humans, by having given us protection from pests such as cockroaches, spiders, fleas etc. therefore, the use chemical pesticides has definitely made life easier for people as without pesticides, life would be most difficult. (9)
As well as providing protection to crops, pesticides also provide protection to the environment such as the use of herbicides, which are used to kill pests like noxious weeds, feral animals etc. Using herbicides to control crop weeds reduces the need for cultivation, thus reducing land degradation. This means that the farmer has increased efficiency as they do not have to put too much money in to farming and it also saves them time and effort as a result. (9)
Despite their many advantages, there are some potential hazards or risks when using pesticides. These risks may be associated with all chemicals whether they be industrial chemicals, pesticides, household products or even natural chemicals found in the environment. Undesirable side effects of farm chemical use usually stem from a lack of understanding of the impact of the chemical on the environment, compounded by indiscriminate and overuse of the product. These side effects do not always occur when farm chemicals are used and damage does not necessarily result.
When chemical pesticides are applied, non-target organisms, including predators and parasites of pests, can also be affected by chemical application. The reduction of these beneficial organisms can result in changes in the natural biological balances and therefore, affecting food chains and other animals in the same food chain. (9) Pesticides are poisons, so in themselves they are extremely dangerous. However, farmers count on the levels used to kill insects being low enough not to affect humans. On the other hand, the main concern associated with pesticides is residues can build up on certain foods over the years and can cause diseases to develop slowly. (7) The over-use of pesticides in the last 50 years has produced a number of ecological problems. These include the appearance of strains, which are resistant to DDT pesticides, toxicity to non-target species, pest resurgence and bioaccumulation. (2)
An example of strain resistance is DDT, which was used very often. This was first used extensively in the 1940s. During the Second World War it was very successful in controlling lice and fleas and reducing diseases carried by these insects. Later, it was used to fight insect-borne diseases, such as malaria, which is a disease carried by some species of mosquito. By the late 1950s, many types of insects, including several species of malaria, had evolved strains resistant to DDT. By 1987, over 500 species of insect had been identified which were resistant to one or more insecticide. (2) DDT is also linked to cancer and male infertility after it was shown to block the action of male hormones. Therefore, it was banned in the developed world. However, some people do argue against this, as they believe that a hazardous chemical like this should be used, as it helps to kill the mosquitoes that carry the disease. (7)
Some scientists believe that exposure to pesticides in the womb may be to blame for the growth of behavioural disorders among children in industrial countries. They have also found out that some pesticides have been found to weaken the immune system, and concern has raised that exposure to pesticides in the womb could make individuals more vulnerable to their toxic effect as adults. (7)
When pesticides are applied, drift of sprays can vaporise during application and can cause severe damage and residue problem in crops, livestock, waterways and the general environment. In the carelessness of pesticides, it can cause the loss of wildlife as the leaching chemicals can be washed into rivers and streams. (9) Residues in food for humans and feed for livestock can be a consequence of direct application of a chemical to the food source, by the presence of pollutants in the environment or by transfer and biomagnifications of the chemical along a food chain. Not all residues are undesirable although good agricultural practice must be observed to prevent unnecessary and excessive levels of residues. (9)
An alternative of chemical pest control is biological control, which does not use chemicals. Instead, it uses other organisms or parasites of the pest, in order to reduce the pest population. It avoids the use of pesticides, with their environmentally harmful effects. It is usually species-specific, so that other similar organisms which are not pests are unharmed. Various groups of organisms are used as biological control agents, including insects, viruses, bacteria and fungi. (2) The first biological control agent was used in 1889 to control the cottony cushion scale insect, a pest of citrus trees. (2)
I have now come to a conclusion, where I believe that chemical pest control should be used in farming as it help to maximise food production and provides crops with high yields. However, this can only happen by ensuring there are adequate safeguards over the manufacture, sale and use of these pesticides and by ensuring that they are used correctly, safely and accurately by well trained and competent applicators.
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Title: What are pesticides?
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Title: Pesticides in agriculture
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