Sun Cancer, Sun Rays & Sun Screens
Skin
Cancer:
There are three major forms of skin cancer.
Basal Cell Carcinoma is the most common form of skin cancer. It occurs most frequently in men who have "high sun exposure" and primarily produces lesions on the head and neck. Basal cell carcinoma rarely spreads throughout the body but can invade neighboring bone and nerves.
Squamous cell carcinoma is the second most common skin cancer. It primarily affects people who "sunburn easily, tan poorly, and have blue eyes and red or blonde hair". Squamous cell carcinoma most commonly develops from actinic keratoses and can metastasize if left untreated. Squamous cell carcinoma of the lip is 12 times more common among men than among women.
Malignant Melanoma is the rarest form of skin cancer but is the most deadly. It affects the cells which produce melanin and seems to be more prevalent among city-dwellers than among people who work out-of-doors. It does not necessarily occur on sun-exposed areas of the body and is thought to be linked "to brief, intense periods of sun exposure and a history of severe sunburn in childhood or adolescence". Malignant melanoma metastasizes easily and is often fatal if not found early.
Ultraviolet Radiation:
UVA rays constitute 90-95% of the ultraviolet light reaching the earth. They have a relatively long wavelength (320-400 nm) and are not absorbed by the ozone layer. UVA light penetrates the furthest into the skin and is involved in the initial stages of suntanning. UVA tends to suppress the immune function and is implicated in premature aging of the skin.
UVB rays are partially absorbed by the ozone layer and have a medium wavelength (290-320 nm). They do not penetrate the skin as far as the UVA rays do and are the primary cause of sunburn. They are also responsible for most of the tissue damage which results in wrinkles and aging of the skin and are implicated in cataract formation.
UVC rays have the shortest wavelength (below 290 nm) and are almost totally absorbed by the ozone layer. As the ozone layer thins UVC rays may begin to contribute to sunburning and premature aging of the skin.
All forms of ultraviolet radiation are believed to contribute to the development of skin cancer, and likewise cause havoc for the rosacea sufferer.
Sunscreens
Sunscreens are designed to protect against sunburn (UVB rays) and generally provide little protection against UVA rays. UVA rays have a depressing effect on the immune system, and are therefore a "setup" for other dermatological problems such as rosacea.
Sunscreens come in two forms:
Chemical sunscreens contain chemicals such as benzophenone or oxybenzone (benzophenone-3) as the active ingredient. They prevent sunburn by absorbing the ultraviolet (UVB) rays. Most chemical sunscreens contain from 2 to 5% of benzophenone or its derivatives (oxybenzone, benzophenone-3) as their active ingredient. Benzophenone is one of the most powerful free radical general known to science. It is used in industrial processes to initiate chemical reactions and promote cross-linking. Benzophenone is activated by ultraviolet light. The absorbed energy breaks benzophenone's double bond to produce two free radical sites. Most chemical sunscreens cause various degrees of redness and sensitivity to rosacea sufferers.
Physical sunscreens contain ingredients such as zinc oxide, sodium chloride, magnesium stearate, polyethylene glycol, iron oxide and sulfur. These physical sunscreens are topical and do not penetrate the skin. They work by reflecting the ultraviolet (UVA and UVB) rays away from the skin. These physical natural minerals as a sunscreen are preferable for rosacea sufferers. Also, you can get further sun protection by applying the chemical sunscreen over the physical sunscreen, which helps to keep the skin from being irritated by the chemical sunscreen.
Basal Cell Carcinoma is the most common form of skin cancer. It occurs most frequently in men who have "high sun exposure" and primarily produces lesions on the head and neck. Basal cell carcinoma rarely spreads throughout the body but can invade neighboring bone and nerves.
Squamous cell carcinoma is the second most common skin cancer. It primarily affects people who "sunburn easily, tan poorly, and have blue eyes and red or blonde hair". Squamous cell carcinoma most commonly develops from actinic keratoses and can metastasize if left untreated. Squamous cell carcinoma of the lip is 12 times more common among men than among women.
Malignant Melanoma is the rarest form of skin cancer but is the most deadly. It affects the cells which produce melanin and seems to be more prevalent among city-dwellers than among people who work out-of-doors. It does not necessarily occur on sun-exposed areas of the body and is thought to be linked "to brief, intense periods of sun exposure and a history of severe sunburn in childhood or adolescence". Malignant melanoma metastasizes easily and is often fatal if not found early.
Ultraviolet Radiation:
UVA rays constitute 90-95% of the ultraviolet light reaching the earth. They have a relatively long wavelength (320-400 nm) and are not absorbed by the ozone layer. UVA light penetrates the furthest into the skin and is involved in the initial stages of suntanning. UVA tends to suppress the immune function and is implicated in premature aging of the skin.
UVB rays are partially absorbed by the ozone layer and have a medium wavelength (290-320 nm). They do not penetrate the skin as far as the UVA rays do and are the primary cause of sunburn. They are also responsible for most of the tissue damage which results in wrinkles and aging of the skin and are implicated in cataract formation.
UVC rays have the shortest wavelength (below 290 nm) and are almost totally absorbed by the ozone layer. As the ozone layer thins UVC rays may begin to contribute to sunburning and premature aging of the skin.
All forms of ultraviolet radiation are believed to contribute to the development of skin cancer, and likewise cause havoc for the rosacea sufferer.
Sunscreens
Sunscreens are designed to protect against sunburn (UVB rays) and generally provide little protection against UVA rays. UVA rays have a depressing effect on the immune system, and are therefore a "setup" for other dermatological problems such as rosacea.
Sunscreens come in two forms:
Chemical sunscreens contain chemicals such as benzophenone or oxybenzone (benzophenone-3) as the active ingredient. They prevent sunburn by absorbing the ultraviolet (UVB) rays. Most chemical sunscreens contain from 2 to 5% of benzophenone or its derivatives (oxybenzone, benzophenone-3) as their active ingredient. Benzophenone is one of the most powerful free radical general known to science. It is used in industrial processes to initiate chemical reactions and promote cross-linking. Benzophenone is activated by ultraviolet light. The absorbed energy breaks benzophenone's double bond to produce two free radical sites. Most chemical sunscreens cause various degrees of redness and sensitivity to rosacea sufferers.
Physical sunscreens contain ingredients such as zinc oxide, sodium chloride, magnesium stearate, polyethylene glycol, iron oxide and sulfur. These physical sunscreens are topical and do not penetrate the skin. They work by reflecting the ultraviolet (UVA and UVB) rays away from the skin. These physical natural minerals as a sunscreen are preferable for rosacea sufferers. Also, you can get further sun protection by applying the chemical sunscreen over the physical sunscreen, which helps to keep the skin from being irritated by the chemical sunscreen.
