is it harmful ?
Yes, Ionizing and non-ionizing radiation in certain conditions are harmful
Radiation
Ionizing radiation in certain conditions can cause damage to living organisms, causing cancer or genetic damage.

Non-ionizing radiation in certain conditions also can cause damage to living organisms, such as burns. In 2011, the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) released a statement adding radio frequency electromagnetic fields (including microwave and millimeter waves) to their list of things which are possibly carcinogenic to humans.

what was the texas revolution? A rebellion of colonists from the United States and Tejanos in putting up armed resistance to the centralist government of Mexico. in which country did the movement originate? Mexico where did this name originate? From the Nahuatl term for the heartland of the Aztec Empire, namely the Valley of Mexico and surrounding territories, with its people being known as the Mexica. which country invaded this empire? Spain how is cortés related to the conquest? He was a Spanish "Conquistador" who led an expedition that caused the fall of the Aztec Empire which king did he defeat? UNANSWERABLE name a regulation followed here. UNANSWERABLE where was cortés  born? In the town of Medellín, now a municipality of the modern-day province of Badajoz in Extremadura, Spain. what is the climate like in this country? The alpine climate, the humid subtropical climate and the continental climates what is the first one like? One simple definition is the climate which causes trees to fail to grow due to cold. what is the reason behind such a climatic phenomenon? The temperature profile of the atmosphere is a result of an interaction between radiation and convection. what is the former phenomenon? It is the emission or transmission of energy in the form of waves or particles through space or through a material medium.
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Radiation [SEP] Possible damage to health and environment from certain types of radiation
Ionizing radiation in certain conditions can cause damage to living organisms, causing cancer or genetic damage. Non-ionizing radiation in certain conditions also can cause damage to living organisms, such as burns. In 2011, the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) released a statement adding radio frequency electromagnetic fields (including microwave and millimeter waves) to their list of things which are possibly carcinogenic to humans. RWTH Aachen University's EMF-Portal web site presents one of the biggest database about the effects of Electromagnetic radiation. As of 12 July 2019 it has 28,547 publications and 6,369 summaries of individual scientific studies on the effects of electromagnetic fields.