Alterations in orientation, migrations and increased mortality are some of the risks of light pollution for fauna. Meanwhile, in human health it manifests itself in sleep disorders, stress generation, and altered metabolism .
LatinAmerican Post | María Fernanda Ramírez Ramos
Listen to this article
Leer en español: La contaminación lumínica amenaza a la salud y biodiversidad
Light pollution for some years has been a growing threat to wildlife and human health. Although it is one of the least talked about types of pollution, it is estimated that more than 80% of the world's population, 99% in the case of Europe and North America, lives under what is known as a lit sky, which refers to to the excess of artificial lights pointing at it.
In this regard, the United Nations Educational, Scientific and Cultural Organization, UNESCO, made a declaration entitled "The Right to Dark Skies" in 2016, declaring it a World Heritage Site. According to the information found in "The New World Atlas of Artificial Sky Brightness" , Latin America is one of the areas of the planet with the least light pollution. However, large cities do not escape the dangers of excess artificial light.
Effects of light pollution on biodiversity
The Convention on the Conservation of Migratory Species of Wild Animals, which has been meeting all year to assess the status of these species, has noted that light pollution kills millions of birds each year. "Natural darkness has conservation value in the same way as clean water, air and soil," said Amy Fraenkel, Executive Secretary of the Convention.
In this way, artificial light causes the natural cycles of darkness and light to be altered. For this reason, birds, turtles and insects, among other species, become disoriented and end up dying prematurely because they become prey, are attracted to cities, where there is danger for them, or fail to reach their migration destinations. and they remain in unfavorable situations for their survival. As for insects, light contamination si responsible for what is known as the insect apocalypse . Research published in the journal Science indicates that there is a risk that around 40% of the world's insects will become extinct in the coming decades.
Light pollution is a threat to migratory birds, causing disorientation when they fly at night????— ipbes (@IPBES) May 11, 2022
It can lead to collisions with buildings, disturbing their internal clocks & interfering with their ability to undertake long-distance migrations.#WMBD2022 #DimLightsforBirds pic.twitter.com/dX8JXl9J53
Effects of light pollution on health
Although many times we are not aware of the subject, like animals, the cycles of light and darkness have an influence on the functioning of the human body. The most obvious effects occur in relation to sleep patterns, as the body is prepared to sleep when it is dark thanks to the production of melatonin. It is a hormone that regulates sleep patterns and is also known as the hormone of darkness. Together with serotonin, which also influences mood, they ensure rest.
Melatonin secretion is regulated by changes that occur in ambient lighting, being released in the dark. However, with light pollution and excess artificial lights, the secretion of said hormone can be inhibited. This means that sleep disorders are increasingly common today, which can influence other situations such as stress, anxiety, metabolism disorders or depression.
On the other hand, excess artificial light has an influence on visual fatigue and the appearance of headaches and migraines. In addition, it can also be harmful to the skin, since the rays it emits can also have UV radiation. For this reason, it is advisable to use sun protection even indoors.
Responsibility of people and governments
Although the great sources of light pollution respond to industries and public lighting, citizens can also take action to mitigate light pollution. In fact, the World Migratory Bird Day , which was celebrated on May 14, had as its motto "Dim the lights for the birds at night".
However, it is urgent that companies and local governments commit to adapting lighting in cities, in order to generate as little light pollution as possible. In this regard, the United Nations pointed out that the countries that participate in the Convention on Migratory Species of Wild Animals approved guidelines on light pollution in which recommendations are made to assess the environmental impact of projects likely to generate this type of pollution. . "Projects need to take into account the main sources of light pollution in a given location, the wildlife species that are likely to be affected, and data on proximity to important habitats and migratory routes," he says. Next year a new conference of said convention will be held that seeks to establish new recommendations.