There is still no evidence mobile phones harm human health, says a major safety review for the UK's Health Protection Agency (HPA).

英国健康保护署一项安全检查称，目前仍没有证据证明手机危害人体健康。

Scientists looked at hundreds of studies of mobile exposure and found no conclusive¹ links to cancer risk, brain function or infertility².

However, they said monitoring should continue because little was known about long-term effects.

The HPA said children should still avoid excessive use of mobiles.

It is the biggest ever review of the evidence surrounding the safety of mobile phones.

There are now an estimated 80 million mobiles in the UK, and because of TV and radio broadcasting, Wi-Fi, and other technological³ developments, the study said exposure to low-level radio frequency fields was almost universal and continuous.

A group of experts working for the HPA looked at all significant research into the effects of low-level radio frequency.

'Relatively⁴ reassuring⁵'

They concluded that people who were not exposed above UK guideline levels did not experience any detectable⁶ symptoms.

That included people who reported being sensitive to radio frequency.

They also said there was no evidence that exposure caused brain tumours⁷, other types of cancer, or harm to fertility or cardiovascular（心血管的） health.

But they said very little was known about risks beyond five years, because most people did not use mobile phones until the late 1990s.

Prof Anthony Swerdlow, who chaired the review group, said it was important to continue monitoring research.

"Even though it's relatively reassuring, I also think it's important that we keep an eye on the rates of brain tumours and other cancers," he said.

"One can't know what the long-term consequences are of something that has been around for only a short period."

There has been speculation⁸ about the health effects of using mobile phones for years.

The HPA conducted a previous review in 2003, which also concluded that there was no evidence of harm. But there is now far more research into the subject.