Since the first use of modern weapons of mass destruction during the First World War, the World has lived in fear of these horrifying instruments of death. Gripped by this fear, countries around the world have continued to research, develop, and test these weapons in the spirit of mutually assured destruction. Over the years, science and warfare have continually refined their methods of human extermination, bringing forth some of the most terrifyingly effective weapon systems ever devised. However, the testing and use of these weapons is often a step into the unknown. The repercussions of deploying these weapons are sometimes not known until after they have been used. Thus, large portions of land have been contaminated in the quest for the ultimate weapon. This thesis explores the effects of CBRN (Chemical, Biological, Radiological, and Nuclear) weapons on the environment. This encompasses the effects on organic life (both the intended targets of weapon deployment and other organisms caught in the effected area) as well as the long-term effects to the areas contaminated. Each element of CBRN is discussed individually with a combination of historical deployment, testing data, and current threat level and prevention. These are followed by an analysis of the current threat of CBRN weapon use and the steps the international community is taking to prevent it. In conclusion, a recommendation is given for implementing policy to prevent CBRN weapon use as well as store or dispose of these weapons to prevent future use.