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The amount of Oxamyl that is lethal to one half (50%) of experimental animals fed the material is referred to as its acute oral lethal dose of fifty or LD50. In rats the LD50 of Oxamyl is 5.4mg/kg. The LC50 of Oxamyl in rats is 37mg/kg. The LD50 of Diflubenzuron in rats is 4640mg/kg, and the LC50 of Diflubenzuron in rats is greater than 10’000mg/kg.
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Most pesticides are resistant to degradation, and there are many factors that determine the persistence of the pesticide in the environment. These include: How easily they evaporate, and how easily they dissolve in water. If a pesticide has potential to evaporate into the atmosphere, and is persistent, then it could potentially travel long distances, and if a pesticide is dissolvable in water then is has a greater potential to get carried off with rain water. Leading to future leaching in soil if the pesticide is still present. Using pesticides decreases the general biodiversity of soil causing lower water retention, meaning the plants will have less water to grow and thrive in the environment. Pesticides also strip the nitrogen from the soil, necessary for the growth of large plants. Animals may be poisoned by pesticide residues on food after the spraying of crops. Aquatic life is also affected by the runoff and transfer of pesticides through the environment, causing underwater plant life to die lowering the oxygen levels in the water and later on killing fish.
Pesticides are carefully regulated in Canada through a program of premarket scientific assessment, enforcement, education, and information dissemination. These activities are shared among federal, provincial/territorial and municipal governments, and are governed by various Acts, regulations, guidelines, directives and by-laws. Although it is a complex process, regulators at all levels work together towards the common goal - helping protect Canadians from any risks posed by pesticides and ensuring that pest control products do what they claim to on the label.
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The use of toxic pesticides to manage pest problems has become a common practice around the world. Pesticides are used almost everywhere, not only in agricultural fields, but also in homes, parks, schools, buildings, forests, and roads. Its not difficult to find somewhere where pesticides aren't used. Pesticide can be a hazard to the environment due to the fact that they can be transferred by wind and air currents. This is called the drift effect. In warm weather these pesticides can also be carried by evaporation as well as in cold climates the pesticides can be carried through condensation. This is called the grasshopper effect. The effect of this can have an impact on animals, plants, and aquatic life when these pesticides are carried through evaporation and condensation.
Worldwide, more than 500 species of insect, mites, and spiders have developed some level of tolerance to pesticides. The twospotted spider mite is a pest of most fruit crops and is notorious for rapidly developing resistance to pesticides and miticides. Some plant pathogens have also become resistant to pesticides. This is bad because pests species evolve and become resistant to a specific pesticide due to natural selection. The most resistant specimen survive and pass on their genetic traits to their offspring. This means farmers will have to use multiple different types of pesticides on their crops to prevent crop loss due to pests.
There are alternatives to using pesticides. These are generally known as sustainable agriculture or alternative agriculture. Under these names there are several practices, some very old, that can reduce the need for, or substantially reduce, the amount or type of pesticides that you may use. Alternative methods have been practiced for some time and include: Crop rotation, polyculture, trap crops, which attract pests away from the valuable crops, reduced use of chemical pesticides, Organic farming, and biological pest control such as pheromones, entomopathogenic fungi, bacteria, and viruses.
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