The average person looks upon a tan as a sign of healthy attractiveness and exposure to the outdoors. However, in recent years medical science has come to appreciate the dangers of exposure to the sun, particularly UVA exposure (320-400 nm of the solar spectrum band) and UVB radiation exposure (290-320 nm). There has been a sharp increase in the frequency of cancer occurring in exposed areas, such as basal cell carcinoma, squamous cell carcinoma and, most dangerous of all, malignant melanoma.
The dangers noted above have recently increased the public's interest in self-tanning compositions. In early versions, self-tanning compositions tended to result in an orange-like appearance which most people found unacceptable. However, even present self-tanning compositions can give the user an `orange` or `fake` appearance due to the relatively large amount of composition applied onto the hand and thereafter applied to the body part to be treated.
Present self-tanning compositions are sold as liquids, creams and gels. Drops are applied to the user's hand, which then serves to apply the solution to the portion of the body, e.g. face, upper torso, etc. to be "tanned". Streaking of the body portion due to uneven application typically occurs. The texture of the user's hands also factors into this streaking effect. Furthermore, this method generally results in an orange or brown pigment being left on the applicant's hands. The user's hands need to be thoroughly scrubbed to avoid later discoloration.
There is also a certain amount of waste in applying the composition to the hand and then onto the body, as well as maintaining containers or bottles of seldom used solution. Most current self-tanners have been found to leave stains on clothes, furniture, etc. if not given time to dry effectively. Treated body parts must be kept clear of such materials for 0.5 to 1.0 hour after application.