Recommended: Use a voucher code MAS5385 to save an extra 5% when shopping for supplements on iHerb.

From the orange halo gracing cities worldwide to the absence of stars in the sky, light pollution is a commonly known problem, but few realize it has impacts far greater than just the ascetics of constellations.  Light pollution has been found in studies to be related to real and pressing human health concerns as well as an ecologically destructive force for a number of species.  What are the human health and ecological risks associated with light pollution and what can we do about these issues?

Human health effects

The human health effects of light pollution stem from a number of physiological repercussions of disrupting the 24 hour light-dark cycle, called the circadian cycle.  Light pollution is linked to, among other conditions, chronic lack of sleep (decreasing the immune responses), decreased levels of melatonin production, and increased risk of both breast and prostate cancers.

As an example of a group of people who suffer from extreme light pollution in their natural cycles, nightshift workers show a number of long-term adverse medical effects caused by excess exposure to light at times that disrupt the natural circadian cycle.  Pregnant nightshift workers suffer a higher risk of late-term miscarriage and stillbirth, and in 2007, the International Agency for Research on Cancer classified night-shift work as a probable human carcinogen.

Light pollution can have tremendous effects on human health over time; however, there are things we can do about it.  If you must work nightshifts, be sure that you recreate your circadian cycle on a different schedule.  The article linked above indicates that permanent nightshift workers had reduced impacts of these effects in comparison to intermittent nightshift workers due to the likely creation of an offset circadian cycle used by the permanent workers.  If you work during the day, advocate lower levels of lighting in office spaces (which are often guilty of excessive lighting).  Minimize the amount of time spent looking at sources of light  outside of natural daylight times.  (Reading this at night?  Go to sleep.)

Ecological effects of light pollution

In addition to the human effects, there are many ecological effects of light pollution, much of which involves animal movement.  Many animals use natural lighting cues, such as positioning of the moon and stars as a component of their innate navigation systems allowing them to migrate, and excess lighting from cities or ill-placed light fixtures can confuse that system in those animals.  One example is the sea turtle, which knows to walk towards the light reflecting off the ocean rather than towards the dark sand dunes in the other direction.  Lighting from beachside homes has been known to distract the turtles from their goal, causing them to die of dehydration or become prey to a number of natural predators.

The story of the sea turtle is just one of many examples.  The National Geographic cites migratory, nocturnal and seafaring birds, and certain reptiles and amphibians as adversely affected by light pollution, pointing out an event where some 50,000 birds following lights flew straight into the ground at Warner Robins Air Force Base in 1954.

As with human health concerns, there are things we can do about this problem.  Turning off lights when they are not in use makes economic sense and helps reduce our direct impact on light pollution.  Installing lighting that points downwards, only lights areas that are necessary and only for times that are necessary is the first step in controlling your surroundings.  After personal changes, we can’t underestimate our power in civic society.  Advocating responsible lighting solutions for our neighborhoods and beyond, as well as treating the night sky as a natural resource which must be conserved just as fresh water or forests, can help educate decision makers that can have a direct impact on the placement and design of urban and rural lighting systems.

The science is in:  Light pollution adversely affects both human health and the environment around us.  However, there are steps we can take to mitigate this effect in both our own behavior and in the design of the lighting around us.  Taking these steps is just one part of reducing our impact on the environment, but an important one.

Featured images:
  •  License: Royalty Free or iStock source:

This is a guest post by Lilly Sheperd. Lilly’s a freelance writer, mainly intersted in healt and green related articles. Nowadays writing on behalf World Market, a company offers the best lighting designs.

Recommended: Use a voucher code MAS5385 to save an extra 5% when shopping for supplements on iHerb.

Leave a Reply

Your email address will not be published.