For parents concerned about their children and for teachers being exposed to wireless technology in schools, this information on health issues from Wi-Fi in Schools is excellent.
Health Issues for Schools
Schools are under pressure
Schools are in a difficult position as they are under pressure to incorporate ICT (information and communication technology) more fully into the curriculum. They are being encouraged to consider Wi-Fi due to the ease of installation and the money saved as a result. The idea that children and staff can use computers at any time and anywhere on the school grounds is an attractive one. But this is only attractive if the technology is safe. Schools need to weigh up the risks from wireless technologies suggested in the scientific literature, the calls for action made by the European Environment Agency, International Commission for Electromagnetic Safety, the Bio-Initiative report and others and address the concerns of parents and staff. Are the educational advantages of wireless computers over similar wired-up ones worth the potential effects on health and development?
Schools need to be safe places for children and young people and provide safe working conditions for their staff.
Children are at increased risk
Children absorb more electromagnetic radiation than adults do. The Stewart Report (2000) states that children absorb more energy per Kg of body weight from an external electromagnetic field than do adults. A 5 year old will absorb around 60% more than an adult (Stewart Report, 2000). Head models have predicted that children (under the age of 8) absorb up to twice the microwave radiation of an adult in peripheral brain tissue (Wiart et al., 2008). Exposures in bone marrow may be up to ten times greater in children than adults (Christ et al., 2010). Children have thinner skulls and their brains are more conductive. Children are still developing and they are likely to be exposed to more radiation over their lifetimes than any previous generation.
Immediate health issues for schools
Of the possible health risks mentioned under 'Scientific Research', some may only become apparent after long-term exposure to wireless technologies. Others may be of more immediate concern for a small number of pupils and staff. Examples are described below:
Epilepsy, male fertility, pregnancy, electromagnetic hypersensitivity, puberty, electrical activity in the brain, cognitive ability, side effects of medicines.
It may be necessary for children who have epilepsy or have experienced occasional seizures not to be in wireless environments at school. Animal studies have shown increased incidences of seizures in susceptible individuals when exposed to low-power microwaves (Lopez-Martin et al., 2006). Mobile phone exposure produces different changes in EEG (electroencephalogram) recordings from humans with epilepsy compared to healthy individuals (Maby et al., 2006). Research is needed to look into whether radiation from wireless technologies increases the incidence of seizures in children with epileptic disorders, or the number of children experiencing seizures. More detail in 'Scientific Research'.
Male staff may prefer not to be in a wireless environment, due to potential decreases in male fertility. Exposure of human sperm to a wireless laptop or mobile phone decreases sperm motility (Avendano et al, 2010; Wdowiak et al., 2007; Erogul et al., 2006; Agarwal et al., 2008; Agarwal et al., 2008b; Fejes et al., 2005). Mobile phones decrease sperm viability and are associated with an increase in the percentage of sperm cells with abnormal morphology/shape. In standby mode, mobile phones significantly decrease sperm motility and count (in rabbits; Salama et al., 2008). Wireless laptops and mobile phone radiation have been shown to damage human sperm DNA (Avendano et al, 2010; De Iuliis et al., 2009) and mouse sperm DNA (Aitkenet al., 2005 ). It is likely that men working with wireless technologies will have reduced fertility. More examples and detail in 'Scientific Research'.
Some pregnant female staff or pupils may feel that the possible risks to the unborn child from exposure to wireless environments are too great. For example, an increased occurrence of behavioural problems has been reported in children whose mothers used mobile phones during pregnancy (Divan et al., 2008; Divan et al., 2010). In rats, very low power mobile phone-like radiation alters gene expression during early gestation (Pyrpasopoulou et al., 2004). It is possible that changes in gene expression, proteins, or at higher exposures damage to DNA, could affect fetal or embryonic development. Indeed, in rats, exposure for 1 hour/day to a mobile phone throughout pregnancy alters the development (in the offspring) of a region of the brain involved in learning and memory (Odaci et al., 2008). Exposure of rats to a mobile phone during pregnancy also decreased the number of follicles (which includes the eggs) in the ovaries of the female offspring (Gul et al., 2009). More examples and detail in 'Scientific Research'.
Schools using wireless technologies need to think of how they will accommodate pupils or staff exhibiting electromagnetic hypersensitivity (EHS, estimates range from 1.5-9% of the population). EHS is a term used for a variety of symptoms believed to be related to exposure to electromagnetic fields. In Sweden EHS is recognised as a functional impairment. The WHO recognise 'EHS is a real and sometimes disabling problem for the affected persons'. However there is controversy about whether EHS is directly caused by electromagnetic fields (EMFs). Affected people are convinced that it is, but many short duration provocation studies have failed to demonstrate a causal relationship between EMF exposure and symptom formation (WHO, 2006). Other studies show physiological changes in sufferers of EHS such as increased numbers of mast cells in the skin (Johansson, 2006) and increased excitability in the cortex in the brain (Landgrebe et al., 2007). Havas et al. (2010) found that some individuals experience cardiac arrhythmias (irregular heart beats) and tachycardia (abnormally fast heart rates) when exposed to a DECT cordless phone or a Wi-Fi router under blind conditions (- the subjects were not aware of when the devices were switched on or off). If schools are aware of EHS and are monitoring for possible adverse reactions to wireless technologies, they have an opportunity to respond by providing safe environments. Symptoms include 'headache, fatigue, stress, sleep disturbances, skin symptoms like prickling, burning sensations and rashes, pain and ache in muscles and other health problems' (WHO, 2006). Some also describe heart palpitations, digestive disturbances, dizziness, eczema or rosacea (WHO, 2006).
Electrical activity in the brain
Electromagnetic fields emitted by mobile phones, or other microwave-emitting technologies, can alter the electrical activity in the brain. Electrical impulses are the way that information is passed along nerve cells in the brain. The cells involved, rate and synchronisation of these impulses are central to brain function and development. Many studies have demonstrated changes in the electrical activity of the brain using EEG recordings when exposed to microwaves (eg. changes in the frequencies of electrical activity (power spectrum) particularly in alpha frequencies, or functional coupling between the two sides of the brain (hemispheres), Lai, 2007; Vecchio et al., 2007 - human; Huber et al., 2003 - human, low power). Often responses have depended on the complexity of tasks that the subjects were carrying out (Lai, 2007). These acute changes do not demonstrate disease or necessarily adverse health effects, but do illustrate changes in brain functioning. In children and teenagers whose brains are still developing, such effects strongly indicate the need for caution, as brain development is modified by the patterns of electrical activity experienced by the brain. The long-term effects of these changes are not yet known. It is possible that the many changes in brain function could over time lead to adverse effects in some people or abnormal brain development.
Prolonged mobile phone use (>25 min/day for 2 weeks) has been associated with a reduction in the concentration of the hormone melatonin in adults (Burch et al., 2002, more examples and detail in Scientific Research). One of melatonin's many roles in vertebrates is regulation of the timing of the onset of puberty. In humans, melatonin concentrations are related to sexual maturation, with significant decreases in concentrations occurring at the onset of puberty (Murcia et al., 2002). However, there is still uncertainty as to whether melatonin is part of the trigger in humans or whether the changes are part of the body's development through puberty (Macchi and Bruce, 2004). In precocious puberty (puberty occurring under the age of 8 in girls, 9 in boys) melatonin concentrations are low (much lower than others in their age group and similar to older children going through puberty; Waldhauser et al., 1981). In delayed puberty, melatonin concentrations remain high but decrease following successful treatment (Arendt et al., 1989).
Studies have not yet investigated a possible link between prolonged exposure to wireless technologies and the timing of the onset of puberty in children. But this is mentioned here because the presence of wireless technologies throughout all primary and junior schools is of concern if it could affect melatonin hormone concentrations and thereby alter the timing of puberty in some children. Studies should really be done to check that children's development and maturation are not affected by excessive exposure to Wi-Fi and similar technologies. More detail in 'Scientific Research'.
Some studies have shown a decrease in cognitive ability (functions such as memory, attention, and decision-making) with exposure to mobile phone electromagnetic fields (especially chronic exposure; eg. Maieret al., 2004 - human; Nittby et al., 2008 - young rats, very low powers, exposure 2h/week for 55 weeks). Other studies have shown no effect; some acute studies have found improvements in cognition (Lai, 2007). The question of whether it is desirable for a technology which should be assisting with education to be having a detrimental effect on cognitive ability in some circumstances needs to be asked. More examples and detail in 'Scientific Research'.
Side effects of medicines
Some pupils or staff on medication could potentially experience central nervous system side effects (effects of their medicine(s) on the brain or spinal cord) due to increased permeability of the blood-brain barrier. For those medicines which do not normally pass through the blood-brain barrier, increased permeability may lead to unwanted effects. More detail in'Scientific Research'.
Schools using wireless technologies need to have policies in place for dealing with potential health issues. Where there are such (potential) immediate health concerns, or for parents not wanting their children to use wireless technologies, schools should be able to provide safe (Wi-Fi-free), wired environments where pupils can participate fully in the educational curriculum. Since there are some reasons for concern, it is not unreasonable for pupils or staff to request wired facilities.
Long-term health issues for schools
Over the long-term it is harder to relate health problems to one particular cause. More long-term studies are needed to investigate the possible link between the use of wireless technologies and disease. However, the possibility of long-term damage is real and applying the precautionary principle seems sensible until more information is available. Scientific research suggests that long-term effects may include cell death in the brain possibly leading to cognitive impairment or dementia, immune dysfunction, damage to DNA, cancers, alteration of normal brain development/activity, behavioural problems, cardiovascular changes and altered hormone concentrations (Bio-initiative Report, 2007; see also Scientific Research).
Since DECT cordless phone use has been associated with an increased risk of malignant brain tumours following 10 years of use (see Scientific Research, Cancer section), school secretaries or those using phones on school business should be informed of the risks and given the option of using a corded phone. Similarly, children should not have to use or be exposed to cordless or mobile phones in school, in keeping with advice from the UK Department of Health (2006) and foreign Governments (see International Concerns). Brain tumours are now the leading cancer killer amongst those under the age of 40 (Braintumourresearch.org). Kevin O'Neill, a consultant neurosurgeon at Imperial College London has said 'Brain tumours are on the increase, reportedly in the region of 2% per year. But in my unit we have seen the number of cases nearly double in the last year' (2009).