GEOG 1070 Lecture Notes - Lecture 13: Organochloride, Food Security, Organophosphate

• School: University of Iowa
• Department: Geography (Geographical and Sustainability Sciences)
• Course: GEOG 1070
• Professor: Jason Mc Curdy

Document Summary

Disease control (insecticides kill pest before a disease-carrying pest is a risk: ex. Of disease = malaria by mosquitos: ddt in sri lanka sprayed to kill pest. Crop protection: pests destroy 1/3 of world"s crop lowers productivity in monocultures, pesticides required for modern industrial ag. Eliminates household pests: reduces spread of disease and reduces damage to house. Chemical: 1st generation pesticides developed, released broad spectrum inorganic toxins (killed everything, nonspecific), included heavy metals that could not get removed from environment. Problem with these was pest would evolve resistance: 1930s to present, development of petroleum-based spray and more natural chemicals. Would utilize a chemical produced by the plant to control. More safe, but not as effective: 2nd generation pesticides developed. 1. chlorinated hydrocarbons-(c, h, cl based), ex. Ddt; kills pest over long time, but it bio accumulates in food chains, persistent. Organophosphates-interferes with nerve function, toxic to humans, but not as persistent in environment.