Electromagnetic radiation produced by nature is also called background radiation of environmental electromagnetic wave  Background radiation has no adverse effect on human living environment  Sunlight is also an electromagnetic radiation, and we have lived up to now only by sunlight for hundreds of millions of years  However, electromagnetic waves emitted by another kind of electromagnetic radiation source will have adverse effects on the environment and harm human health  The data show that electromagnetic radiation pollution sources in the environment include all electronic instruments, devices and equipment invented, manufactured and used by human beings that can produce electromagnetic waves
Sunlight radiation is a kind of background radiation.
 This kind of electromagnetic radiation source is called electromagnetic wave radiation pollution source