Environmental Light Pollution Increases Risk Of Breast And Prostate Cancers

Technology is only good when it is properly used in a way that it does not ignite an environmental health issue. The use of modern, super-lit technological equipment is great but when it threatens our environmental health, it calls for concerned action to limit its effect on the environment. In both the industrialized and developing countries, it is becoming very difficult to avoid light pollution even if we knew about the harmful effects of the environmental exposure to night light.  This unconcerned acceptance to the impression that, it is after all 'only light', may be the reason for the increased risk to breast cancer, in women, and prostate cancer in men, in our industrialized society.

 There is a growing concern among environmental pollution specialists about the health effects of the long term decrease in melatonin, a naturally occurring hormone which can only be produced at night or in the dark, in the human body. This hormones is chiefly responsible for regulating sleep and wake cycles. Although quite a few other factors may be responsible for blocking the production of melatonin by the pineal gland in the brain, one of them being old age, light pollution at night has been implicated in many environmental pollution studies.

Light pollution has been identified as as a serious environmental health issue. This has even gained awareness around the world, leading International Agency for Research on Cancer (IARC), a branch of the World Health Organization (WHO) to classify light pollution as a high grade cancer risk among night shift workers. Environmental pollution specialists have discovered that long exposures to bright night lights tend to decreases the human body's ability to produce melatonin and sadly enough, this form of environmental pollution has been linked to high incidences of breast cancer in women and prostate cancer in men, especially in people in night shift jobs who are exposed to bright lights. This environmental pollution issue calls for great concern, because of the facts at hand, especially as it has to do with breast cancer. Data on cancer shows that after skin cancer, breast cancer is the most common cancer among women in the US, and it is the second leading cause of cancer death in women, after lung cancer.

A quick explanation of this work is necessary. Exposure to bright night light hinders melatonin production by specialized eye nerve cells (primitive ganglion eye cells) in the photosensitive retina. These nerve cells have high sensitivity to blue wavelength. In the instances of night light pollution, these eye nerve cells are triggered to produce blue light (similar to daytime sky light) which is sent to our brain's Supra Chiasmatic Nuclei or SCN, a group of brain cells that control our 'biological clocks'. When this happens, the SCN turns of the pineal gland, a small gland located in the brain, which also turns of melatonin production. When it is dark or there is little or no light, the eye nerve cells do not produce blue light and SCN does not stop melatonin production. Even at weak amounts of night light pollution, melatonin production is suppressed by the pineal gland. Without the health benefits of melatonin, the activities of other hormonal glands will go unchecked and this may lead to increased risk of cancer.

A group of researchers lead by Dr. Fuad Faresand Adina Yokler, Orna Harel and Hagit Schwimmer carried out a study to identify the link between light pollution, decreased melatonin production and increased breast and prostate cancer risk on four groups of lab mice injected with cancerous cells and exposed to different duration of light and darkness, and treated with melatonin. Their results showed:

1. A link between light pollution and cancer

2. The suppression of melatonin production increased tumor development

3. Melatonin suppression is associated with to bright night light.

Melatonin, according to research studies, when released in to the body system can both suppress cancer growth and cause death of cancer cells. It also controls the activities of other hormone-producing glands like the ovaries. It suppresses the activities of estrogen, progesterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH). These hormones are know to cause rapid breast cell growth which may cause error in genetic coding, leading to breast cancer.

Free radicals account for about 70% of biological damage to DNA proteins and cellular membranes, leading to production of cancer cells. While most antioxidants can clean up these free radicals, they do not permanently eradicate them as these free radicals can be released into the body, recaptured and again, causing more damage. Melatonin oxidizes and permanently breaks apart these radicals, making sure they are not released into the body again. A single melatonin molecule has been proven to consume up to 10 free radical molecule species.