1st Generation Pesticides: 1  2500 BC- farmers began using the toxic chemical sulfur to kill off pests from their crops. 2  15th century AD -a variety of chemicals such as, arsenic, hydrogen cyanide, mercury and lead were put to use. 17th century -nicotine sulfate, derived from tobacco leaves was discovered as an effective pesticide and ants were controlled with mixtures of honey and arsenic.
Cell phones communicate with nearby cell towers mainly through radiofrequency (RF) waves, a form of energy in the electromagnetic spectrum between FM radio waves and microwaves. Like FM radio waves, microwaves, visible light, and heat, they are forms of non-ionizing radiation.
Radio Waves Radio waves have frequencies ranging from 3*10 1 to 3*10 9 Hz (30 Hz to 3 GHz) and wavelengths from 10-1 m to 10 7 m (100 mm to 10,000 km). Radio waves are produced from the alternating current of an LC circuit. Radio waves carry information through modulation. Radio, television, cell phones, and remote controls all use radio waves.