Rachel Tseng
This was a week to rejoice. My friend had bought a gauss meter that measures extremely low frequency (0 to 500 mG) electromagnetic field (EMF). I borrowed this device, and immediately began to measure EMF levels in the house, dormitories, areas where children play, garden, and supermarkets that I regularly visit. Although I have learned quite a fair bit about EMF through my translation work, the results from my EMF detection exercise were very alarming. I believe you will be interested in knowing these rather informative findings. Before I proceed with my findings, let me provide some background information about EMF.
Background on EMF
Electromagnetic field is a blanket term for electrical and magnetic fields. The electric field is a measure of the electric force a charge object can exert on other objects entering its field. When our body gets close to a television set or computer monitor, our hair may stand on end because of the presence of static electric fields. Magnetic fields arise from the movement of electric current and vary directly with the strength of the electric current. The unit of measurement of magnetic field intensity is the oersted (Oe) or ampere/metre. What we generally refer to as magnetic field relates to magnetic flux density, measured in tesla (T), gauss (G), or milligauss (mG). The unit of measurement used in this article is the mG.
We use 60 Hertz power supply in our homes and workplaces. This power supply simultaneously creates electrical and magnetic fields. When an electrical appliance is connected to a power point, a small amount of EMF is created. When we turn on the appliance, the EMF level is significantly raised. Note that our exposure to EMF is drastically removed by moving away from the electrical appliance (EMF strength is inversely related to the square of the distance from the source). Hence, we should be concerned about areas where we stay for an extended period of time, or about appliances used at close proximity that we cannot avoid using. However, be particularly mindful of the strength of external sources of EMF. EMF from high-voltage power cables can extend to several hundred metres. Note that EMF measures vary depending on the time of the day. At peak electrical usage, EMF from electrical wires can be as high as that of high-voltage power cables.
Research generally highlights the harm caused by magnetic fields, which can penetrate almost any object. Electrical fields, on the other hand, can be blocked by many objects, including houses and trees. However, recent research also points out the harm to one’s health caused by electrical fields. My current empirical findings relate only to magnetic fields, as the gauss meter measures only magnetic fields and not electrical fields.
How high must magnetic field be before it influences our health? In 1995, two large Scandinavian childhood epidemiological studies investigated common ailments among children. They found that magnetic fields increase the risk of children contracting cancer (particularly, lymphoma, leukemia and brain tumours). This risk increases exponentially from 2mG onwards. According to an article by Dr. Kjell Hansson Mild, Dr. Barry Wilson, and Cindy Sage (an EMF consultants), long-term exposure to magnetic fields of 3mG strength increases the risk of getting cancer by 53%; this risk goes up to above 600% for exposure between 4mG to 5mG. Research also points out that certain household appliances can cause cancer: electric blanket, black and white television sets, hair dryers (as used on children; no evidence with respect to use on adults), and certain models of electrical heaters.
In actual fact, long-term exposure to over 1mG of radiation can cause interference to your health. Dr. Lai told me that during the period she stayed at a place where the magnetic field was 1 to 2mG, she received no inspiration at all and could not write any article. She had to resort to going into the deep mountains to write her essays, and eventually moved house. Nonetheless, do you know that the magnetic field readings that I detected far exceed these numbers?
Evidence on magnetic field levels in our surroundings
- The electric meter is a source of high magnetic field. The reading directly in front of the electric meter exceeded 100mG. Take care if you have a meter directly outside your room. The reading directly on the wall behind the electric meter was 8mG and was 1 to 3mG (depending on electrical usage at time of measurement) for the chair and bed directly behind the electric meter. Be aware of the magnetic field on the bed, as this is the place, we generally spend the most time (in the day, we tend to move from place to place that vary in their magnetic field). Furthermore, our own energy fields tend to be weaker at night. Imagine how big the impact is if you are sleeping in a high magnetic field bed!
You can see that having a bedside stereo system is not a good idea. I detected readings as high as 100mG on a typical radio, above 150mG on a CD player, and above 130mG on an electric alarm clock/radio clock.
The electric alarm clock is particularly harmful because it emits red LED numbers. In principle, keep electrical appliances away from your bed.
- Around the double bed in my friend’s bedroom, I detected readings of 0.2mG on one side of the pillow and 0.6mG on the other side. I then found that on the side that had the higher reading, the reading on the adjacent wall was 7mG, originating from the electrical wiring within the wall.
My friend’s mother was concerned about the relatively high magnetic field readings in her grandchild’s room and asked that we re-assess the readings in her room. She turned on the light for us to assess, and we found that the reading on the wall adjacent to the head of the bed was now higher at 5mG. We measured other parts of the room to find a better place to locate the bed and found that readings taken earlier that were originally low were now higher. We then took readings of the standing halogen torchiere lamp and found that the readings were high only at its top, and at the knob controlling its brightness. Once a distance was kept from the lamp, the readings went down. In fact, there was no significant reading on the seat near the lamp. However, because the halogen torchiere lamp was one that consumed large amounts of electricity, it caused the magnetic fields around the wiring on the wall to increase. When we turned down the intensity of the lamp, the reading on the wall beside the bed also went down, even though the lamp and the bed were on opposite sides of the room.
This incident shows that the use of energy-saving appliances is not only environmentally friendly, but also has direct positive influence on our health.
- My friend complained that she did not sleep well at night. We found two large electric heaters in the room next to her, and close to her bed. The heaters are often put in the children’s room to warm up the room during cold weather. However, a small electric heater can generate magnetic fields up to 200mG and above.
The air-filter also generates considerable magnetic fields. Avoid using it when there are people in the room or place it in a spot furthest from you.
Air conditioners also consume large amount of electricity. Keep your bed and chairs at least a meter away from the air conditioner.
- Microwave ovens emit exceedingly high magnetic field. It is different from other appliances in that even if not in use, the magnetic field on the control panel can reach 30-60mG; when in use, the level reaches over 200mG.
Microwave leakage under 100mW in these ovens (compared to 5000mW for older models) is considered to be within “safe limits”. However, these limits far exceed the new limit of 0.001mW established by scientists. In addition, Hanna Kroeger reminds us that microwave leakage is particularly harmful to male’s reproductive system, and boys should specifically keep away from these microwave ovens. The energy of the food cooked by microwave ovens is low (the height of wheatgrass grown using microwaved water is only half that grown using boiled drinking water). Scientists have also discovered that the radiation can be transmitted from the food to the human body. When you eat microwaved food, you are exposing yourself to microwave radiation.
Therefore, you should stop using the microwave oven.
- The electric motor is a source of high magnetic field. In the kitchen, the refrigerator emits high magnetic field, particularly when it is cooling down and makes a humming noise. Then, the heat discharge system at the back or bottom of the refrigerator radiates magnetic field 10 to 100 times higher than normal (the reading is 1-9mG at the front of the refrigerator, and up to 300mG at its back).
If the refrigerator is not efficient, the humming noise will be long and loud. Dr. Lai shares the following observation: if you use a vacuum cleaner to remove the soot and dirt on the heat discharge system (once every few months), this will improve the efficiency of the refrigerator and reduce the home’s magnetic field.
- The stove ventilator (used to remove oil fumes) in the kitchen is another source of magnetic field, but it is one that cannot be easily avoided. If the manufacturer can design the device so that the motor is placed further and deeper into the wall, the housewife will be less affected. On some stove ventilators that I tested; the reading exceeded the maximum reading on the gauss meter (more than 500mG). In the area facing the housewife’s head, the strength of the magnetic field can reach 10-50mG.
The electric stove poses another similar problem. The higher the temperature, the greater the power consumption, and the higher the magnetic field. You can use the back burner to slightly reduce exposure to the magnetic field. If you have a small kitchen, and simultaneously use the stove ventilator, electric stove and microwave oven, with the refrigerator beside you, imagine the amount of magnetic field that you are exposing yourself to!
We should feel sorry for the housewife who has to spend long periods of time in the kitchen. However, the microwave oven can be discarded, the electric stove replaced with a gas stove, and the use of the stove ventilator can be avoided if we eat raw food and cook food with less oil.
Small appliances can discharge very alarming magnetic field. My blender had readings of over 500mG (some electric shavers and electrical toothbrush have similarly high levels of radiation). The use of different motors makes a difference. More powerful or cheap low-quality motors have high radiation levels. You can consider moving away from the appliance after you have turned it on.
If your family has the habit of gather around an electric stove to have steamboat during winter, you may want to give it up. The electric stove emits high magnetic field (over 500mG).