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.
The cell phone needs much less power essentially because: The receiver on top of the cell tower affords to be much more sensitive than the receiver you can cram inside a mobile phone. (this accounts for most of the difference in needed output power on both sides) It transmits on a slightly lower frequency band, thus bearing a slightly lower propagation loss. (some 2dB, you'd make do with 2/3 of the power)