How will environmental factors like temperature, humidity and light affect the formulation?
After insecticides are applied to surfaces, they are subjected to various environmental factors that reduce their effectiveness. High temperatures have been shown to reduce residual effectiveness of chlorinated hydrocarbon and OP insecticides. The effect of humidity on OPs appears to depend on the type of surface treated. Generally, insecticides with higher vapor pressures volatilize (e.g., evaporate away from treated surfaces) more rapidly in the same environments than those with lower vapor pressures. The loss of insecticide residue by volatilization is greatest on non-absorbing surfaces. Vapor pressures are known for each active ingredient and may be obtained by reading the Material Safety Data Sheet (MSDS) provided by pesticide manufacturers. Keep in mind, however, that formulation can affect vapor pressures. For example, microencapsulation protects the active ingredient within a polyurea shell, making the active ingredient practically non-volatile. Other environmental factors such
