“Balancing your laptop on your knees could cause permanent discolouration of the skin and, in rare cases, cancer,” warned the Daily Mail . The story is of a 12-year-old boy who developed a skin condition caused by the heat from a laptop that was balanced on his bare legs.
The condition, erythema ab igne, is also known as “toasted skin syndrome”, and is characterised by mottled-looking skin resulting from prolonged exposure to heat or an infrared source. Since 2004, there have been at least 10 reported cases of the condition or of burns related to laptop use.
This is a rare condition, but the connection between it and laptops has been documented several times before. The incidence is likely to become more frequent as laptops become more widespread.
The skin damage itself is usually harmless and has no symptoms. As reported, there is a chance that the condition can develop into cancer, but this is a small risk. Simple common-sense precautions can remove this risk. The researchers suggest using a heat-protective barrier between the skin and the laptop (such as the laptop bag), or placing the machine on another surface.
Where did the story come from?
The study was carried out by researchers from the Department of Dermatology at University Hospital Basel, Switzerland. It was published in the peer-reviewed medical journal Pediatrics .
What kind of research was this?
This was a case report of a 12-year-old boy who developed a skin condition called erythema ab igne, caused by the heat from a laptop that was balanced on his bare legs. The researchers also carried out a review of the literature on the skin condition. Erythema ab igne is indicated by discolouration and mottling of the skin, and is caused by prolonged exposure to an infrared heat source.
What did the research involve?
The case report was of a boy who had presented to the emergency department with marks on one of his upper legs. The researchers also carried out a literature search for studies of similar cases in a review of the topic. They found that nine cases of laptop-induced erythema have been reported since 2004, plus one case of a burn produced by a laptop.
What were the basic results?
The boy had a brownish coloured, mottled area on the upper part of his left leg. He reported playing computer games for several hours a day for several months, balancing the laptop on his upper legs. He recognised that the laptop grew hot on the left side (where the optical drives are located), but he did not change his position.
The review found that all nine other patients diagnosed with laptop-induced erythema also had similar damage on the upper leg, which had developed after several months of laptop use. Average laptop use was given as six to eight hours a day.
How did the researchers interpret the results?
The researchers point out that the heat produced by a computer can reach 44ºC, which is enough to cause this condition. Putting the computer on the lap may also block the ventilation fan, increasing the heat even more. They say that, at present, there is no treatment for this condition. Initially, the mottling and discolouration is mild and transient, but tends to become permanent and can also cause skin wasting. Typically, the skin changes are on the left leg as the fan and battery are on that side of a laptop.
The discolouration usually causes no symptoms, but some sufferers have reported burning and itching.
The researchers say it is possible that the skin damage could develop into burns, as mild to moderate heat between 43 and 47ºC is enough to result in burns.
The researchers say that there is a small risk of skin cancer developing in the long term, so it is important that patients with persistent skin damage are monitored. However, it would be best to prevent the condition from developing in the first place by “eliminating the heat source”.
This straightforward case report and review describes a case of skin damage caused by the heat from a laptop. The researchers searched for similar cases and found that nine have been reported since 2004.
Laptops are becoming increasingly widespread, and the number of hours children spend on them is increasing. This news story has helpfully alerted the public to the modest risk posed by these devices.
The risk is small however, and can be easily dealt with by simple common-sense measures, such as using a heat-protective barrier between the skin and the laptop, or by placing the machine on a surface.
Analysis by Bazian
Edited by NHS Website
Links to the headlines
Daily Mail, 5 October 2010
Daily Mirror, 5 October 2010
Links to the science