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Pest control falls into three major categories: chemical, physical, and biological. Chemical is by far the most widely used, primarily because of its affordability. Chemical controls can be classified into three groups: inorganic, synthetic organic, and natural organic. Inorganic insecticides are desiccants, which use silica, or boric acid based, which are poison. Synthetic organic pesticides have been widely used since World War II. During the last 60 years synthetic organic insecticides have been made more pest specific, less poisonous and less environmentally damaging. But still they present a certain amount of risk to human and environmental health. Natural organic insecticides are generally less controversial, but they may not always do the job.
Note the different uses of the words "organic" here, which can be confusing. Organic farming is a component of sustainable living, and generally uses no pesticides at ...