Hybrid Cars
- In recent years there has been an increase in the demand for hybrid cars in Israel.
- Usage of hybrid cars involves exposure to low frequency magnetic fields. Because of the daily use of hybrid cars, the issue of exposure to magnetic fields arises.
- It should be noted that using hybrid cars is a consumer’s decision, similar to using mobile phones or home electrical appliances. Yet, the average exposure durations when using hybrid cars are longer than with other electric consumer goods. Therefore, there is a need to examine the possible health risks involved with prolonged exposure in hybrid car use.
Information on this subject can be found in the following article:
Do Hybrid Cars Emit Radiation?
The hybrid car, as its name implies, combines propulsion partly based upon energy from traditional fuel and partly from electric energy that accumulates during motion. Electric currents used in the electric part of propulsion while driving, create a surrounding low frequency magnetic field. Within the electromagnetic spectrum of non-ionizing radiation, exposures from hybrid cars are in the low frequency radiation range, where electric grid frequency exposures also belong.
The power of magnetic fields created in hybrid cars differs from car to car according to the automobile make and model, and there are even differences between different cars from the same manufacturer and the same model. Also, the distribution of the power of the fields, in the car’s interior, varies from place to place within the car. The location of maximal exposure in the car depends upon the type of car and the location of its electric power unit and the passage of cables within it. The exposure to magnetic fields from cables is higher near the car’s floor. It should be noted that the power of the fields is also dependent upon driving conditions and particularly on changes in the car’s speed (deceleration/ acceleration/ braking).
There are studies evaluating the power of magnetic fields created by hybrid cars, however as there are no uniform international standards for measurement it is difficult to make an exposure estimation.
In 2010 the Ministry of Environmental Protection convened a national public expert committee on the subject of magnetic fields from the electricity grid to discuss exposure to magnetic fields in automobiles. The committee did not find any professional organization or state in the world that placed any restrictions on the marketing and/or use of any hybrid car, as a result of the relatively high magnetic fields liable to be created within it (under certain circumstances during the course of the journey), both in absolute terms and also compared to conventional gasoline and diesel powered cars.
Also a search conducted by the Tnuda Center in several countries, found no restrictions of hybrid car use due to exposure to the magnetic fields created in them.
Are measurements of radiation from hybrid cars being conducted?
According to the Non-Ionizing Radiation Law of 2006, the Ministry of Environmental Protection is charged with granting permits for sources of non-ionizing radiation, however, according to the law, hybrid cars do not require radiation permits.
At the same time, since the Ministry of Environmental Protection encourages the use of hybrid cars with the goals of reducing air pollution from transportation, the subject of hybrid cars was discussed in depth by the ministry and explanations, reasons and positions can be found on the Ministry’s website (in Hebrew).
In addition, the Ministry published results of magnetic field measurements, measured in various hybrid vehicles on its website. In the table of data on radiation exposure measured in hybrid cars in Israel, the average annual exposure level in the various vehicles checked is noted, based on the assumption of 18 weekly hours spent in the car, on average.
What are the health effects of exposure to low frequency magnetic fields?
Most studies that have dealt with the effects of prolonged exposure to low levels of magnetic field on health have focused on examining a possible association with the development of childhood leukemia.
In 2002, based upon population studies published on this subject in 1999, the International Agency for Research on Cancer (IARC) decided to classify magnetic fields of electricity grid frequency as a possible carcinogen in humans (2B).
This decision was based predominantly on pooled analyses. The design of these studies was population studies evaluating a possible association between residency near high voltage electricity lines and the development of leukemia. The results of these studies showed that prolonged exposure to relatively high levels of magnetic fields (greater than 0.3 – 0.4 micro-tesla, equivalent of 3 – 4 milligauss) causes an increase of 1.5 to 2 times in risk of developing this disease. It should be noted that most of the laboratory studies on tissues, cells and animal models did not succeed in affirming the existence of this association. Also, to this day, there is no known bio-physical mechanism of action that could unequivocally explain the association observed in the epidemiological studies.
Therefore, and despite the lack of support for a causative association, it was decided in Israel to act according to the precautionary principle.
What are the permissible levels of exposure to radiation from electrical appliances in Israel?
A legislative policy regulating exposure thresholds for magnetic and electric fields from electrical appliances has not yet been established in Israel.
In general the Ministry of Environmental Protection and the Ministry of Health recommendations for very low frequency radiation for the maximum permitted level of exposure to radiation from electrical appliances are:
- 2000 milligauss for short term exposure (momentary exposure)
- Daily average of 4 milligauss, measured on the "busiest" day (continuous and prolonged exposure)
There are two definitions of continuous and prolonged (or chronic) exposure:
- Exposure of more than 4 hours per day for at least five days a week.
- Exposure of a person in a residence, educational institution, elderly home, hospital, office or open public space used as a playground, are considered continuous and prolonged (regardless of the exposure duration).
It should be noted that studies dealing with evaluation of exposure to radiation emitted from hybrid cars are based on ICNIRP recommendations. Their exposure threshold relates to thermal health effects of acute exposure and does not relate to non-thermal (chronic) effects (mostly the development of cancer).
