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.
Cell phones have a low-power transmitter in them. Most car phones have a transmitter of 3 watts. A hand held call phone operates on about 0.75 to 1 watt of power. The radio waves that send the encoded signal are made up of electromagnetic radiation propagated the antenna.he charts focus on the specific absorption rate, or SAR, of a cellphone, which is a way of measuring the quantity of radio frequency energy that is absorbed by the body, according to CNET. For a phone to pass F.C.C. certification, that phoneâs maximum SAR level must be less than 1.6 W/kg (watts per kilogram).