Photographer : Gordon Waddell |
What is a pesticide?
A pesticide is a chemical that protects plants and animals from various harmful pests. Pesticides are typically divided into four categories:
- insecticides, which kill unwanted insects
- herbicides, which kill unwanted plants, such as weeds
- fungicides, which kill unwanted fungus
- growth promotants, which help plants and animals grow bigger than normal.
Most plants produce their own natural pesticides, however many farmers now use artificial pesticides to protect their crops. Many household agents contain pesticides as well , including flea and tick sprays, or bathroom disinfectants, some swimming pool chemicals, and some lawn and garden products, such as weed killers. Most pesticides work like a nerve agent, breaking down the central nerve endings of the plants or animals they kill.
So, what’s the debate?
Many people, including farmers, argue that pesticides are necessary for global trade. Many countries won’t buy food that hasn’t been properly sprayed with pesticides. Others argue that without pesticides, most of the world’s crops would die. Prices for food would rise tremendously, and land would have to be ploughed more, which would lead to over-farming and land destruction.
Those who argue against pesticide use warn of the health risks involved. If pesticides are directly inhaled or consumed (if you’re around the spraying area, or there is still some residue on the food you’re eating), they can lead to symptoms ranging from fatigue and skin rashes to nausea and even death. Pesticides can also run off into waterways, polluting streams and rivers. Recent studies have also proven links to a significant increase in the chance of developing Parkinson's disease and exposure to pesticides.
Because pesticides are chemical-based, they often do not decompose properly, and can remain in soil and water for years. Similarily, concerns of bioaccumulation (increase in concerntration of a pollutant from the environment to the first organism in a food chain) and biomagnifications (the increases in concentration of a pollutant from one link in a food chain to another) are tied into pesticide use. The classic example is DDT, a pesticide used in the past to control mosquito populations, lice, and to protect crops. DDT is persistent in soil and can be quickly absorbed by organisms, which then pass the chemical on to their predators, and so on throughout the food chain. While DDT has since been banned in most devloped countries, DDT still continues to linger in within the environment.
Do Australian farmers use pesticides?
Yes. But if you’re worried, you should know that Australian farmers use substantially fewer pesticides than farmers in the US or UK.
The most popular kind of pesticide used in Australia is herbicide. Glyphosate herbicides are used most often. Glyphosates are non-selective herbicides, which mean they kill any kind of plant they come into contact with. This means that the crops that farmers want to survive the herbicide must be genetically modified.
Is there a solution?
Biologically-based pesticides are increasing in popularity and are considered safer than chemical pasticides. Examples of biologically-based pesticides would be pheremones, microbial pesticides, and genetic engineering. Introduction of natural predators of the targeted pests is another method of control some farmers have tried, some with great success.
This page has been updated by Laura318.
How do I know this?
Australian Academy of Technological Sciences and Engineering, Pesticide use in Australia, http://www.atse.org.au/uploads/Pesticide%20Use%20i...
Australian Government, Department of Agriculture, Fisheries and Forestry, http://www.affa.gov.au/content/ministers.cfm
Brandon, H 2002, 'Doing a world of good: benefits of pesticides', Delta Farm Press, 3 May, http://deltafarmpress.com/mag/farming_doing_world_...
Food Standards Australia and New Zealand, http://www.foodstandards.gov.au/mediareleasespubli...
Organophosphate Insecticides, http://npic.orst.edu/RMPP/rmpp_ch4.pdf
Wikipedia Free Encyclopedia, Fungicide http://en.wikipedia.org/wiki/Fungicide
Wikipeida Free Encyclopedia, Herbicide http://en.wikipedia.org/wiki/Herbicide
