Organophosphates are chemicals in insecticide used extensively in agriculture. When people, such as agricultural workers, are exposed to large quantities of organophosphates, these chemicals can be harmful. Organophosphates can be very toxic. However, certain classes of this group are more poisonous than others. Overall, t he effects of an organophosphate will depend on the type of chemical the person comes into contact with, concentration of exposure, length of time and way the person is exposed. A highly concentrated solution or large amount in the air is more likely to cause severe effects, including death.