Evidence that blue light from devices like mobile phones causes sleep disturbance is still unclear, with more research needed says the International Commission on Non-Ionizing Radiation Protection (ICNIRP).
Experts from the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) contributed to ICNIRP's latest statement on short wave light exposure from indoor artificial sources and its effect on human health.
Short wave light, which is also called blue light, is from the visible light part of the electromagnetic energy spectrum and it is detectable by the eye.
ARPANSA's Radiation Research and Advice Director, Associate Professor Sarah Loughran, is a sleep expert.
She says the worrying trend of increased screen time at the cost of essential behaviours such as sleep should not be ignored.
'Delaying sleep onset by being on your phone and engaging in activities on screens that might keep you awake will affect alertness and sleepiness,' A/Prof Loughran says.
'What is less clear is whether blue light from mobile devices is affecting sleep, so until we know more, ARPANSA recommends putting your phone away when you should be sleeping.'
In the past couple of decades, the use of mobile devices such as smart phones, laptops and tablets has increased exponentially resulting in more light entering our pupils at night, which is a time when our bodies want to rest.
More than 1.6 billion computers, TVs and mobile phones are sold globally each year, which indicates a large proportion of the global population is spending time in front of artificial light-emitting devices.
ARPANSA's Health Impact Assessment Assistant Director, Associate Professor Ken Karipidis, is the ICNIRP Vice-Chair elect. He says it's important to know more about the impact of artificial light exposure on sleep as poor sleep negatively affects health.
'ICNIRP's latest statement shows that there is conflicting evidence on whether short wave light exposure affects sleep quality and alertness - some studies show an affect, while others don't,' A/Prof Karipidis said.
'We need more research before we can determine what exposure guidelines may be necessary to protect people from blue light exposure.'
'Among other things, ICNIRP's statement has suggested that the measurement of light exposure needs to improve in future studies to understand its effect on human health.'
As Australia's primary radiation protection authority, ARPANSA works with leading international health authorities like ICNIRP to develop evidence-based guidelines and statements that protect people and the environment from radiation.
While there is not a clear scientific consensus on the possible impacts of blue light, there are known benefits to sleep hygiene from reducing on-screen distractions.
'Whether it's blue light, streaming a gripping drama or receiving constant social media notifications that's keeping you up at night, reducing your screen time before bed may help you get a good night's sleep,' said A/Prof Loughran.
