·        Pesticides are generally classified as any substance, or mixture of substances, that are intended to prevent, destroy, repel or generally mitigate any pest.

·        These are toxic substances and range from simple disinfectants, to heavy duty farming insecticides.

·        Pesticides are created in two general methods. Some are derived through chemical processes, these are generally more potent. Others are created naturally, some plants have even developed the ability to secrete pesticides

·        Pesticides can come in 4 varieties:

·        Insecticides

·        Fungicides

·        Rodenticides

·        Herbicides

Herbicides

·        Herbicides are pesticides that focus on harmful, or unwanted plants.

·        Herbicides are designed to target specific crops. This is so that they can be used to blanket treat agricultural fields.

·        One problem faced because of herbicide overuse is resistance to the herbicides

Insecticides

·        Insecticides are pesticides that target insects

·        They can target either the Adult, Larvae or the eggs of a species

·        Problems arise as many insecticides are also toxic to humans, all harm the environment, and many are subject to bio magnification.

Fungicides

• Fungicides are pesticides that target either grown fungi, or the fungal spores.

• Fungicides are used both in agriculture and to fight fungal infections in animals.

• There are two different varieties of Fungicide: either be contact or systemic

• Contact Fungicides kill when they impact the fungus

• Systemic Fungicides enter into the target fungus and are absorbed. They kill the fungus from the inside out.

Rodenticides

• Rodenticides are pesticides that are focused on killing rodents.

• Rodents, because of their scavenger eating habits are difficult to kill through poison use.

• To be effective rodenticide must be tasteless and odorless in lethal concentrations, and have a delayed effect so that rats eat the whole dosage before dieing.

• There are 3 groups of rodenticides:

• Anticoagulantschemicals that inhibit blood clot formation. Death is usually caused in 1-2 weeks

• Metal phosphides, quick acting and highly lethal. The acid in the digestive system of the rodent reacts with the phosphide to generate the toxic phosphine gas, killing the rodent in 1-3 days.These are useful for areas where rodents have developed resistance to anticoagulants.

• Hypercalcemiaapoison that manipulates the calcium levels in a rodent, causing various health problems. After ingestion of a lethal dose, the calcium levels are raised sufficiently that blood vessels, kidneys, the stomach wall and lungs are calcificated. Heart problems develop, bleeding caused by damage to capillaries and possibly kidney failure.

Bibliography:

http://en.wikipedia.org/wiki/Insecticide

http://en.wikipedia.org/wiki/Rodenticide

http://www.epa.gov/testmike/oppsrrd1reregister/rodenticides/

http://science.howstuffworks.com/insecticide-info.htm

http://en.wikipedia.org/wiki/Herbicides