Light of the world

Experts from around the globe gathered at Leicester’s De Monfort University in the UK this week to discuss ‘artificial light’ and how it is not only affecting the world we live in but is also increasingly helping define it.

The fact that light at night affects us adversely more than we might think is not something many of us give a second thought to - let alone consider it necessary to be discussed at an international conference.

But those at ALAN 14 - the second ‘Artificial Light at Night’ annual conference - had a significantly different take and highlighted a number of concerns that need to be taken seriously.

The scientists and researchers had travelled from the different parts of the UK, Ireland, the United States, Europe and Australia to present their findings on light-related topics and related research across the fields of health, biology, pollution, ecology, technology and design.

ALAN 2014 examined the use of artificial lighting at night in all its forms, as well as the spectrum of adverse effects that artificial light at - known collectively as light pollution - night may cause.

The theme coming through loud and clear is that society at large is barely beginning to recognising that such liberal and indiscriminate use of illumination is at a mounting cost to both the environment and ourselves.

Interestingly, an increasing number of scientific studies are now seriously questioning the long-held premise that humans are largely immune to the effects of artificial light at night.

Research is now confirming that artificial light - even in quite small doses - disrupts sleep, confuses circadian rhythms and impedes the production of the hormone melatonin.

All of which is bad news if the consequences of excessive exposure to light at night really do include an increased risk for obesity, diabetes, cancer and cardiovascular disease.

Back in 2012 the American Medical Association (AMA) called for more research into the risks and benefits of occupational and environmental exposure to artificial light at night and for the introduction of new lighting technologies at home and at work that minimise circadian disruption.

Technological advances such as LEDs (light-emitting diodes) have improved the potential for better targeted lighting - but for now they are often brighter and more intrusive than the old lights they are replacing.

Much of our modern light - whether from TVs, computer screens, smart phones and electronic gadgets or from outdoor lighting of one form or another - is also ‘blue’ rich and so proves even more disruptive to the 24 hour biological process that regulates the body's functions.

According to conference organiser Prof Martin Morgan-Taylor, of the School of Law, De Montfort University, Leicester, and a Legal Advisor to the UK Campaign for Dark Skies, the physiological effects caused by lighting may be similar to noise.

"Admittedly, there are comparatively few studies as yet on the problems caused by lighting, but lights can and do wake people up, just as does noise," he said.

"Moreover, with light it appears that the subject does not need to be fully awakened to suffer the same negative effects as someone who has been deprived of sleep altogether."

This means that people's health can even be adversely affected by ‘security’ floodlighting and, what the Chartered Institute of Environmental Health (CIEH) refers to as, ‘light briefly turning on and off' during the night.

Prof Morgan-Taylor stated the research concerning cancer risks does not restrict itself to lighting that wakes the subject because risk factors are akin to the levels of night-time light entering a bedroom.

Paul Marchant, of Leeds Metropolitan University, questioned the widely held perception of ‘improved’ (brighter) lighting is always beneficial in reducing road accidents and crime.

The generic objection to this - based on the premise that light equals protection and darkness represents danger - is that we need all this light for safety and security, he said.

Such common belief goes a long way to explain why many supermarkets, petrol station forecourts and car parks, as well as our own driveways and yards, are lit more than ten times as brightly as they were just 20 years ago.

"In fact, the issue of light at night and safety is rather more complex, and there is little compelling evidence to support widespread such mis-assumptions," he said.

"Ever-brighter lights can, for example, actually diminish security by casting glare that impedes vision and creates shadows where criminals can hide."

Emma Marrington, CPRE Dark Skies campaigner and author of ‘Shedding Light’, a survey of local authority lighting policies, said some local authorities are taking steps in the right direction.

She said the research had revealed no evidence to support the fear that adjusting or dimming street lights impacted on public safety.

"We urge councils to do more to control lighting in their areas and ensure that the right lighting is used only where and when it is needed."

"We're not advocating changes where they're not appropriate - but why shine bright lights on residential streets, quiet roads and open countryside throughout the night when they are not needed?"

The consistent theme emerging from ALAN 14 was that there are many different aspects to artificial light at night and the effects on our well-being, ecology and life in general are only just beginning to be understood.

We will, no doubt, continue to tinker with the natural world and all its variances, and the exponential growth of artificial light in our homes and across the planet shows now time of dimming yet.

In the meantime, conferences like ALAN will gradually produce evidence in an attempt to redress the balance.

And one day there may come a time of new enlightenment - when we release that at certain times of the day we need dark more than light.


The conference was hosted by Leicester De Montfort Law School, De Montfort University, and co-organised with the EU COST Action LoNNe (Loss of the Night Network) in association with the International Dark Sky Association. My thanks to Martin Morgan-Taylor and Katie Scott.