Warning on Wi-Fi Health Risk to Children

By Nic Fleming, Medical Correspondent
Last Updated: 10:51PM BST 19 Apr 2008

According to estimates, half of all primary schools are already using wireless networks

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Children should not place computers on their laps while they are using wireless internet connections because of potential health risks, according to a leading Government adviser.

Professor Lawrie Challis, who heads the committee on mobile phone safety research, called yesterday for pupils to be monitored amid mounting public concern over emissions from wi-fi networks.

He is concerned that few studies have been carried out into the level of exposure in classrooms and believes that if health problems do emerge they are likely to be more serious in children.

Prof Challis, is chairman of the Mobile Telecommunications and Health Research Programme, an 8.4 million investigation, funded by the Government and the industry, into the potential health risks of mobile phones.

He said that until more research had been carried out, children who used wi-fi enabled laptops should only do so if they kept a safe distance from their embedded antennas.

Prof Challis said: "With a desktop computer, the transmitter will be in the tower.

"This might be perhaps 20cms from your leg and the exposure would then be around one per cent of that from a mobile phone.

"However if you put a laptop straight on your lap and are using wi-fi, you could be around 2cms from the transmitter, and receiving comparable exposure to that from a mobile phone.

"Children are much more sensitive than adults to a number of other dangers, such as pollutants like lead and UV radiation, so if there should be a problem with mobiles, then it may be a bigger problem for children.

"Since we advise that children should be discouraged from using mobile phones, we should also discourage children from placing their laptop on their lap when they are using wi-fi.

"In view of public concern, I should like to see some measurements of intensities arising from wi-fi made in schools."

Last week it was revealed that Sir William Stewart, the chairman of the Health Protection Agency, told colleagues that he would like to see monitoring of children exposed to wireless technology in schools.

In the past 18 months approximately 1.6 million wi-fi connections have been set up in British homes and offices, and about one in five adults owns a wireless-enabled laptop.

According to estimates, half of all primary schools and four fifths of all secondary schools are using wireless networks.

Wi-fi works through the transmission of radio waves between a router, which is connected to a telephone line, and a small transmitter in a computer.

Under international guidelines the amount of energy absorbed into the body from such radio waves cannot exceed two watts per kilogram when averaged over any 10 grams of tissue.

The maximum signal strength next to the router or computer transmitter is 0.1 watts and the power level falls off very rapidly beyond a few cms from the transmission points.

However it is believed that a classroom containing 20 laptops and two routers could combine and be equivalent to the emission from a mobile phone.

Jeff Hand, professor of imaging physics at Imperial College London, said: "If we are talking about health issues linked to localised heating of tissue then these will be insignificant at the power levels we are talking about here."

But while most scientists only recognise potential health effects from mobile phones linked to heating, others believe there could be "non-thermal" effects.

Alasdair Philips, the director of Powerwatch, the consumer group, said: "We are not talking about problems caused by heating. Our brains and nervous systems work by using electrical signals. I believe these signals are being interfered with by exposure to this wi-fi radiation.

"Based on studies reporting effects experienced by people living near mobile phone masts, I would predict chronic fatigue, memory and concentration problems, irritability and behaviour problems - exactly what we are seeing increasingly in our school pupils. "

Prof Challis has backed Sir William's recommendations in his 2000 report that children under 15 keep mobile phone use to a minimum and be encouraged to text rather than call.

The Health Protection Agency also advises children to limit their use of mobiles.

The Austrian Medical Association is pressing for a ban on wi-fi in schools. Dr Gerd Oberfeld, Salzburg's head of environmental health and medicine, has described wi-fi as "dangerous" to sensitive people.

A Department of Health spokesman said: "Wi-fi devices are of very low power, much lower than mobile phones. The only firm precautionary advice issued by the Health Protection Agency is about children's use of mobile phones."

?A report into the possible link between high-voltage cables and cancer has urged the Government to consider restricting homes and schools within 200 feet.

But the study, commissioned by the Department of Health, stopped short of recommending a specific ban.

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为何反对“槟城无线”及“WiMax无线上网”

为何反对“槟城无线”及“WiMax无线上网”
Reasons to Oppose wireless@penang and WiMax@penang

槟州政府计划在未公开谘询下推展wireless@penang及WiMax@penang全槟无线上网计划，其中wireless@penang涉及在全槟安装750个无线电波发射接收器(access point)，发射接收器将24小时发送无线电波，提供Wi-Fi上网服务，含盖地区包括住宅区、学校、公园、医院、商业购物中心等等，使到人民将面对24小时不间断的无线电磁波笼罩。WiMax@penang则涉及兴建电讯塔作为发送电磁波，其发射距离可远达50公里。

Wi-Fi在不少国家引起关注，包括德国政府劝告尽量避免，此外一些政府也劝告学校避免装Wi-Fi，一些大学或是学校也因为Wi-Fi潜在的健康影响，拆除或是放弃Wi-Fi。WiMax则是更新的科技产品，其发送功能更强。

目前科学界尚未针对Wi-Fi潜在的健康影响进行全面研究，不过却已提出警告，因为Wi-Fi使用2.4GHz频率，与手提电话(0.9或1.8GHz)或电讯塔的频率接近；WiMax则使用更高的频率发送。

wireless@penang及WiMax@penang将深入民居，对成长中的小孩、婴孩、孕妇、老人、病人以及电磁敏感者将带来最直接的影响；在槟州消费人协会及一些民间组织已发出声明反对wireless@penang及WiMax@penang后，槟州政府有必要向人民说出Wi-Fi及WiMax的背后“真相”。

政府及医药公会等发出警惕
Advice and Warnings from Governments

2007年德国政府发布警告，人们应该尽量避免使用Wi-Fi，因为这项技术可能给人体健康带来危害，德国官方防辐射部门(The German Federal Ministry for Radiation Protection [Das Bundesamt für Strahlenschutz])还建议，人们应该尽可能用固话代替手机，德国环境部表示，未来将就减少个人辐射展开积极的宣传。

奥地利Salzburg的环境保健及医药主任Dr Gerd Oberfeld形容Wi-Fi对敏感者“危险”，劝请学校不要装Wi-Fi。

2007年、欧盟环境署(European Environmental Agency)劝告警惕曝露Wi-Fi电波下，直至进一步的报告。欧洲环境局两个结论，一个是国家IO工作组的科学研究报告，认为以前对辐射的安全限制过于宽松，现在造成的人体长期累计暴露于辐射的情况是前所未有的；第二个结论，因此不能排除Wi-Fi致癌的可能。

2007年9月，欧盟再次劝请立即行动减少面对Wi-Fi，行动电话、及电讯塔的电磁曝露，并劝告任何延误将造成健康危机，一如石棉、抽烟及有铅汽油。

澳洲医药公会劝告以电缆取代Wi-Fi。

奥地利医药公会(Austrian Medical Association)要求禁止校园内装Wi-Fi。

奥地利Salzburg政府、法兰克福(Frankfurt)地方教育局及德国教师公会禁止及劝告学校不要安装Wi-Fi。

欧盟环保及保健行动计划2004至2010年的中期检讨报告中针对Wi－Fi及WiMax等，关注电磁波造成的健康危险，报告也指出电磁曝露的安全限制已“过时”(obsolete)。

学校的行动
Actions by Schools and University

英国、法国在教师及家长反对下拆除校内Wi-Fi，在2007年12月法国卫生及保健委员会(Hygiene and Security Commitee)劝告拆除巴黎各公共图书馆及博物馆的Wi-Fi。

加拿大湖首大學（Lakehead University）以長期使用無線上網可能危害健康為由，下令校園全面禁止無線上網。湖首大學校長吉伯特表示，無線上網科技可能會對人體有害，尤其是對年輕人，根據「加州公共設施委員會」研究及相關文獻指出，電磁輻射可能會造成血癌和腦瘤。雖然研究結果未經臨床證實，但吉伯特以可能對學生健康有害為由，下令禁止校園使用無線上網。

威尔斯Carmarthenshire郡的Ysgol Pantycelyn学府在家长反对下拆除Wi-Fi，该郡也考虑是否全面禁止校园装Wi-Fi。

2007年，英国伦敦Haringey地方政府(Haringey Council)推动校园内禁止Wi-Fi运动。

英国的Stovwe学校在一名音乐教师在安装Wi-Fi后头痛而拆除Wi-Fi。

美國芝加哥橡樹公園小學的家長會三年前以無線上網會導致兒童記憶喪失或神經損害為由，對學校提出告訴，要求學校禁止無線上網。

科学家及非政府组织及政府议员等的劝告
Advice by Scientists and Researches

Bristol大学的人类辐射系教授Dennis Henshan要求针对Wi-Fi的危险性进行调查。

Norwich的国会议员要求针对Wi-Fi的风险进行调查；此外教师专业公会也要求教育部进行调查。

英国一项报告显示WiFi将加速儿童自闭症的症状。

英国卫生保护局，已经决定对Wi-Fi及其应用展开更深入的系统研究。

中国全国政协委员、信息产业部电信研究院科技委副主任雷震洲在3月28日的通信业环境友好发展论坛上表示，需要对诸如Wi-Fi这样的技术所带来的环境和健康风险保持警惕。

台灣環保聯盟會長陳椒華則說，電磁波對人體的危害很大，會造成癌症、白血病、流產等疾病，因此瑞士在六年前立法通過的電磁波環境背景值數據，「比台灣環保署現行的建議參考值嚴格八十到一百倍」，環保署對於無線上網毫無規範措施，政府應盡快擬定「建構無線上網城市」的環境背景值。