Plastic watches found to carry radiation risk

IRISH scientists have expressed concern about new research which indicates that some plastic fashion watches may expose their wearers to excessive levels of cancer causing radiation.

Austrian researchers have found that some people who wore plastic watches have been exposed to many times the maximum recommended level of radiation.

The watches have been found to leak tritium, a radioactive form of hydrogen, which is used to make them luminous.

The Radiological Protection Institute of Ireland (RPII) is to examine the discovery by scientists from the University of Innsbruck, which was made during tests on consumer products.

"It's very important that people avoid any unnecessary dose of radiation. Tritium has essential uses, for example, in safety lights, but there are alternatives available for watches which do not give rise to such levels of radiation," said Mr John Cunningham, assistant chief executive of the RPII.

However, Mr Cunningham emphasised that it was "very unlikely" that tritium could prove dangerous. The radiation it emitted was "non penetrating" and was more likely to be absorbed by the body of the watch or the skin than to enter the body.

Dr Peter Mitchell, director of UCD's radiation physics research laboratory, suggested that watchmakers could be prosecuted if it were shown they had not used the best available technology to minimise the radiation dose.

According to the Austrian findings, which are published in the journal Health Physics, the average dose of radioactivity to the skin of those wearing the watches was 183 millisieverts - almost four times the maximum level set by the International Committee on Radiological Protection.

"That is a quite significant skin dose. If it's shown to be true, the scientists are quite right to be concerned," said Dr Mitchell.

To test whether a watch contains radioactive materials, place it in a drawer for at least half an hour. If the hands are still clearly visible, the watch contains a radioactive source of light.