April 26, 2021 - Why is there concern that cellular telephones may cause cancer?

April 26, 2021 Puzzle Piece

Why is there concern that cellular telephones may cause cancer?

There are three main reasons why people are concerned that cellular telephones (also known as “wireless” or “mobile” telephones) may cause certain types of cancer.

• Cellular telephones emit radiofrequency (RF) energy (radio waves), which is a form of radiation and is under investigation for its effects on the human body (1).
• Cellular telephone technology is relatively new and is still changing, so there are few long-term studies of the effects of RF energy from cellular telephones on the human body (1).
• The number of cellular telephone users has increased rapidly. As of December 2007, there were more than 255 million subscribers to cellular telephone service in the United States, according to the Cellular Telecommunications and Internet Association (CTIA). This is an increase from 110 million users in 2000 and 208 million users in 2005.

For these reasons, it is important to learn whether RF energy from cellular telephones affects human health.
 
What is RF energy and how can it affect the body?

RF energy is a form of electromagnetic radiation.

Electromagnetic radiation can be divided into two types: ionizing (high-frequency) and non-ionizing (low-frequency) (2). RF energy is a form of non-ionizing electromagnetic radiation. Ionizing radiation, such as that produced by x-raymachines, can pose a cancer risk at high levels of exposure. However, it is not known whether the non-ionizing radiation emitted by cellular telephones is associated with cancer risk (2).
Studies suggest that the amount of RF energy produced by cellular phones is too low to produce significant tissue heating or an increase in body temperature. However, more research is needed to determine what effects, if any, low-level non-ionizing RF energy has on the body and whether it poses a health danger (2).

How is a cellular telephone user exposed to RF energy?



A cellular telephone’s main source of RF energy is produced through its antenna. The antenna of a hand-held cellular telephone is in the handset, which is typically held against the side of the head when the telephone is in use. The closer the antenna is to the head, the greater a person’s expected exposure is to RF energy. The amount of RF energy absorbed by a person decreases significantly with increasing distance between the antenna and the user. The intensity of RF energy emitted by a cellular telephone depends on the level of the signal sent to or from the nearest base station (1).

When a call is placed from a cellular telephone, a signal is sent from the antenna of the phone to the nearest base station antenna. The base station routes the call through a switching center, where the call can be transferred to another cellular telephone, another base station, or to the local land-line telephone system. The farther a cellular telephone is from the base station antenna, the higher the power level needed to maintain the connection. This distance determines, in part, the amount of RF energy exposure to the user.

What determines how much RF energy a cellular telephone user experiences?

A cellular telephone user’s level of exposure to RF energy depends on several factors, including:

• the number and duration of calls
• the amount of cellular telephone traffic at a given time
• the distance from the nearest cellular base station
• the quality of the cellular transmissions
• how far the antenna is extended
• the size of the handset
• whether or not a hands-free device is used