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.
Buildings, trees, hills, mountains, etc. all diminish a tower's transmission distance. Cell phones use regular line of sight radio signals. The more stuff that is in that line of sight between you and the tower, the less signal that gets through. You can't have cell sites running at 300+ watts and get better coverage. This is fine for a one-way device like a beeper because your beeper doesn't have to transmit back.