Cordless Phone

April 3, 2008

Cordless Phones

by Maria Garcia Alvarez

Cordless phones are not all the same. They come in either analog or digital form and theyoperate in a range of frequencies, from radio to microwave. Common analog cordless phones that operate around 900MHz (the low end frequency of a microwave oven) are being replaced by new digital phones that operate at 2.45 – 5.8 GHz (microwave ovens operate around 2.5GHz) and with more power. Analog phones present health hazards, but the new, high-frequency Digitally Enhanced Cordless Telephones (DECT) seem to be much worse. DECT phones emit microwave radiation very similar to cell phones. But, a cell phone’s handset automatically turns down its output once a link is established, while a DECT always sends out the same strength signal. Moreover, while the power of the signal from older analogue cordless phones is at a constant level (10 mW), the signal from a DECT is sent in bursts – 100 bursts of high power (250 mW) per second.

If you use a DECT close to its main base unit, you are exposed to two separate doses of radiation – one from the handset and one from the base. When in use, DECT phone handsets emit low frequency magnetic field pulses into the side of the your head as well as high frequencymicrowaves, easily capable of penetrating walls. Meanwhile, the charger units give off high levels of low frequency magnetic fields along with pulses of microwaves 24 hours a day.

( )

Emissions from a cordless phone charger can be as high as six volts per meter (yard) – twice as strong as those found within 100 meters (yards) of mobile masts. Six feet away from the charger the radiation is still as high as 2.5 volts per meter (yard), which is 50 times the “safe” level; you have to be 100 meters (yards) away before the emissions drop to a “safe” 0.05 volts per meter (yard). (

Interesting studies about radiation and effects from DECT phones and baby monitors: ,,

Health Risks

The most common cancer caused by such radiation is leukemia. But breast cancer, brain tumors, insomnia, headaches and erratic behavior in kids have also been linked. Investigations (Hardell & Mild, 2003) of thousands of cases of brain tumors and mobile phones of all types has found up to a 50% increased risk of a brain tumor after five years, which doubles after ten years


Another Lennart Hardell paper on mobile phone use and brain tumors shows an increased brain cancer risk for long-term over 5 years of regular cordless phone use (

Radio wave sickness from all sources, including cordless telephones, has become widespread in the US over that last decade. Symptoms include: Insomnia, headaches, dizziness, nausea, memory loss, difficulty concentrating, irritability, respiratory illness (bronchitis, sinusitis, pneumonia), flu-like illness, asthma, fatigue, weakness, pressure or pain in the chest, increase in blood pressure, altered pulse rate (usually slowed), pressure behind the eyes, other eye problems, swollen throat, dry lips or mouth, dehydration, sweating, fever, shortness of breath, muscle spasms, tremors, pain in the legs or the soles of the feet, testicular or pelvic pain, joint pain, pains that move around the body, nosebleeds, internal bleeding, hair loss, digestive problems, skin rash, ringing in the ears, impaired sense of smell, pain in the teeth (especially with metallic fillings)

Electro-smog (a popular term for all artificially produced electrical and magnetic fields, including that coming from cordless phones) affects the body in several ways:

Energetic effect (thermal): it damages the organism by individual molecules, cells or organs being fed so much energy that they are totally or partly destroyed (principle of a microwave oven)

Signal effect: An organism can convert even the weakest fields into powerful biological responses which can result in disturbances in the hormone balance, biorhythm, psyche and the immune system.

Electro-stress: An enormous variety of tiny waves penetrates into the body. The human body comprises billions of particles, all of which wish to move or to oscillate with the waves like tiny compass needles. This is not possible, as the cells are part of a firm tissue and fixed cell structures. This fight to “break away” ends in a “physical long-term stress”.

( )


1. Stay away from 2.4 GHz and 5.8GHz DECT phones unless you know you can get a new generation phone that only transmits from the base when the handset is lifted. (Nothing is available in the US yet, but in Europe, I found Rowtex Limited, which distributes OrchidLow Radiation phones, and FRITZ!F, which makes a phone with an “eco-mode”.)

2. A better choice is to use the lower frequency (900 mHz) analog cordless phones. The transformer emits a constant EMF, and both the handset and the base unit of analogue cordless telephones emit detectable microwave radiation when making or receiving calls, BUT the base unit/charger on analogue cordless phones does not emit detectable microwave radiation when the phone is not in use.

3. If you use a cordless phone, keep the charger as far away from occupied spaces as possible, and definitely away from the bed.

4. Consider using only phones with cords (the old fashioned kind), at least as the only phone that is permanently connected. You can keep the cordless phones unplugged until you need to use them.


Find out more about our school: