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According to the National Toxicology Program Report on Carcinogens from the US Department of Health and Human Services, broad-spectrum UV radiation is a carcinogen whose DNA damage is thought to contribute to most of the estimated 1.5 million skin cancers and the 8,000 deaths due to metastatic melanoma that occur annually in the United States.
In the average human adult it is estimated that 50 to 70 billion cells die each day from apoptosis. One of the largest promoters of apoptosis is exposure to ultraviolet (UV) light. While UV light is essential to human life it can also cause harm by inducing cancer, immunosuppression, photoaging, inflammation, and cell death. [1]
The Sun's UV output is divided into UV-A and UV-B: solar UV-A flux is 100 times that of UV-B, but the erythema response is 1,000 times higher for UV-B. [citation needed] This exposure can increase at higher altitudes and when reflected by snow, ice, or sand. The UV-B flux is 2–4 times greater during the middle 4–6 hours of the day, and is ...
“Skin cancer is the most common cancer in the U.S., and unprotected exposure to the sun’s harmful ultraviolet rays is a major risk factor for skin cancer,” the AAD stresses in its official ...
[3]: 39–40 Radiation therapy can also cause radiation cancer. [ 3 ] : 40 With interventional fluoroscopy, because of the high skin doses that can be generated in the course of the intervention, some procedures have resulted in early (less than two months after exposure) and/or late (two months or more after exposure) skin reactions, including ...
When radiation deposits enough energy in organic tissue to cause ionization, this tends to break molecular bonds, and thus alter the molecular structure of the irradiated molecules. Less energetic radiation, such as visible light, only causes excitation, not ionization, which is usually dissipated as heat with relatively little chemical damage ...
The searing heat from wildfires can transform metals found naturally in the soil into cancer-causing airborne particles, according to a new report.. While a growing body of research has focused on ...
However, UVA is now known to cause significant damage to DNA via indirect routes (formation of free radicals and reactive oxygen species), and can cause cancer. [23] Visible range or light spans 380 to 700 nm. [24] As the name suggests, this range is visible to the naked eye. It is also the strongest output range of the Sun's total irradiance ...