A new type of light pollution has become more prominent in much of Europe as LEDs are increasingly used in outdoor lighting, a team from the University of Exeter has found. In their paper published in the journal Science Advances, the team describes their study of photographs taken from the International Space Station.
Previous research has shown that artificial light in the natural environment can adversely affect wildlife and humans. For example, studies have shown that both animals and humans experience disrupted sleep patterns, and that many animals are confused by light at night, causing a range of survival problems.
In the new study, officials point out that officials in many countries have been advocating the use of LED lighting instead of traditional sodium bulbs on roads and parking areas. To learn more about the impact of this change, the researchers obtained photos taken by astronauts on the International Space Station between 2012-2013 and 2014-2020. These photos provide a better range of light wavelengths than satellite images.
Through the photos, the researchers were able to see which regions of Europe had converted to LED lighting and to what extent. They found that countries such as the UK, Italy and Ireland experienced significant changes, while others such as Austria, Germany and Belgium experienced little change. Since LEDs emit light at different wavelengths than sodium bulbs, an increase in blue light emission can be clearly seen in those areas that have been converted to LED lighting.
The researchers noted that they have found that blue light interferes with melatonin production in humans and other animals, which can interfere with sleep patterns, so increased blue light in LED-lit areas could negatively impact the environment and the people who live and work in these places. They suggested that officials had better study the impact of LED lighting carefully before moving forward with new projects.