Excessive artificial lighting at night is increasingly being identified as a serious environmental and public health issue worldwide.
According to a study published in the scientific journal Nature, global nighttime artificial light emissions increased by 16% between 2014 and 2022, while overall light intensity rose by 9%.
Researchers warn that uncontrolled lighting from:
- Street lamps
- Advertising billboards
- Vehicle headlights
- Commercial buildings
is disrupting natural biological cycles in both humans and wildlife.
Health Impact on Humans
Scientists say excessive exposure to bright artificial light at night interferes with the body’s natural sleep-wake cycle.
In particular, cool white lighting that resembles daylight can suppress production of:
- Melatonin
Reduced melatonin levels have been linked to increased risks of:
- Obesity
- Diabetes
- Sleep disorders
- Other long-term health complications
Impact on Wildlife and Ecosystems
The report also highlights severe consequences for nocturnal animals and ecosystems adapted to natural darkness.
Among the effects identified:
- Migratory birds become disoriented while navigating using stars and moonlight
- Some bird species lay eggs prematurely
- Billions of insects die after being attracted to artificial lights
- Fireflies struggle to find mates
- Nocturnal mammals such as Bats lose habitat access
- Artificial light near waterways disrupts fish migration routes
The study notes that light pollution has increased sharply in:
- China
- India
- The west coast of the United States
Meanwhile, parts of Europe have recorded a 4% reduction in light pollution due to:
- Energy-efficient lighting systems
- Reduced industrial activity
- Stronger environmental regulations
Countries such as:
- France
- Czech Republic
- Slovenia
have introduced measures including:
- Turning off commercial lighting late at night
- Directing streetlights downward
- Limiting electricity consumption
The city of Fulda in Germany has become a notable example.
Officials there say motion-activated lighting reduced insect deaths by 90%, while the city was also recognized as Germany’s first “star city” for preserving dark skies.
Experts recommend several simple steps to reduce light pollution:
- Using warm yellow lighting below 3000 Kelvin outdoors
- Turning off unnecessary lights
- Closing curtains at night
- Using targeted lighting instead of excessive floodlights
Researchers say these measures can help protect ecosystems, conserve energy, and improve human health.
