Figure 1: Basic Electromagnetic Physics

Figure 1: Basic Electromagnetic Physics

Figure 2: The Electromagnetic Spectrum

Figure 2: The Electromagnetic Spectrum

Figure 3: Reflected, Transmitted and Remitted Light

Figure 3: Reflected, Transmitted and Remitted Light

Figure 4: Light Rays

Figure 4: Light Rays

Figure 5: UV and DNA

Figure 5: UV and DNA

Figure 6: Penetration of UV Light into Skin

Figure 6: Penetration of UV Light into Skin

UVB Sunscreens (290–320 nm)

Following is the list of UVB sunscreens from the Federal Register in 1999 approved in the United States.

• Aminobenzoic acid (PABA) up to 15%
• Avobenzone up to 3%
• Cinoxate up to 3%
• Dioxybenzone up to 3%
• Homosalate up to 15%
• Menthyl anthranilate up to 5%
• Octocrylene up to 10%
• Octyl methoxycinnamate up to 7.5%
• Octyl salicylate up to 5%
• Oxybenzone up to 6%
• Padimate O up to 8%
• Phenylbenzimidazole sulfonic acid up to 4%
• Sulisobenzone up to 10%
• Titanium dioxide up to 25%
• Trolamine salicylate up to 12%
• Zinc oxide up to 25%

UVA Sunscreens (320–400 nm)

So far, only the following are FDA- or EU-approved UVA sunscreens include the following.

• Avobenzone up to 3%
• Bisdisulizole disodium up to 10%
• Diethylamino hydroxybenzoyl hexyl benzoate up to 10%
• Ecamsule up to 15%
• Methyl anthranilate up to 5%

Fitzpatrick Skin Types and the Sun

Type I. This type always burns and never tans in the sun. It is extremely susceptible to skin damage and skin cancers, both basal cell carcinoma and squamous cell carcinoma. In addition, Type I has a very high risk for melanoma. These individuals must use a sunscreen with an SPF of 30+, as well as wear protective clothing while avoiding the sun as much as possible. Help these clients check their skin and make sure that you refer them to a dermatologist to have an annual professional skin checkup.

Type II. This type almost always burns and rarely tans in the sun. Type IIs are extremely susceptible to skin damage and skin cancers, including basal cell carcinoma and squamous cell carcinoma. In addition, Type II has a very high risk for melanoma. See Type I for skin protection recommendations.

Type III. This type sometimes burns and sometimes tans in the sun. It is susceptible to skin damage and skin cancers, both basal cell carcinoma and squamous cell carcinoma, and is at risk for melanoma. Type IIIs need a sunscreen of at least SPF 15+ every day, should wear sun-protective clothing and should seek the shade between 10 am–4 pm. Help these clients check their skin and make sure that you refer them to a dermatologist to have an annual professional skin checkup.

Type IV. This type tans easily and is less likely to burn, yet is still at risk for skin damage and skin cancers. Type IVs should use a sunscreen with an SPF 15+ and should avoid high-intensity exposure between 10 am–4 pm. Help these clients check their skin and make sure that you refer them to a dermatologist to have an annual professional skin checkup.

Type V. This type tans easily and rarely burns, yet is still at risk. Type Vs should use sunscreens with an SPF 15+ and avoid high sun intensity between 10 am–4 pm. A type of melanoma known as acral lentiginous melanoma (ALM), a very nasty form of the disease, is more common in Type V individuals who generally have darker skin. ALM is the fourth distinct variant of cutaneous melanoma. It is the most common type of malignant melanoma in darker-skinned people, but is relatively infrequent in Caucasians. It occurs predominantly in the sixth, seventh, and eighth decades of life, with a peak incidence in the seventh decade for males and in the sixth decade for females. These lesions are usually located on palmar, plantar and subungual skin. Because these melanomas tend to appear on parts of the body rarely exposed to the sun, they often remain undetected until after the cancer has spread, so help your Type V clients check unexposed areas of the body, such as the soles of the feet, palms of hand and mucous membranes.

Type VI. This type is very similar to Type V, although it doesn’t burn. Like Type V, individuals who are Type VI should use a sunscreen with an SPF 15+ and avoid high sun intensity between 10 am–4 pm. This type is more susceptible to ALM, as well. See Type V for more information and treatment recommendations.