Background on UV radiation
UV radiation refers to the electromagnetic radiation with a wavelength between 100 and 400 nm. UV radiation from the sun is classified into three bands:
- UVA (315 – 400 nm)
- UVB (280 – 315 nm)
- UVC (100 – 280 nm)
The ozone layer in the stratosphere blocks nearly all of UVC radiation and more than 90% of UVB radiation from reaching the earth’s surface. Thus 94% of UV radiation reaching the earth’s surface consists of UVA rays and only 6% consists of UVB rays.
Other than the sun, UV radiation is also artificially generated by man-made UV equipment which has found applications in various industrial, research and commercial settings. One area of concern that may pose a threat to human health is sun-tanning equipment (also known as sunbed or sunlamp) which consists of multiple UV sources used for extended exposure on the skin at close proximity.
Examples of Sun Tanning Beds
Risks and adverse health effects associated with UV exposure
According to the World Health Organization (WHO), overexposure to UV radiation from the sun and artificial sources is of considerable public health concern. UV radiation is a key contributor to the development of skin cancer, cataracts and other eye conditions, and suppresses the immune system. Cumulative exposure to UV radiation also results in premature skin ageing. Such adverse health effects are associated with sunbed use due to their emission of UV radiation.
There is increasing evidence from both experimental and epidemiological data that cumulative exposure to UV radiation increases the risk of skin cancer. Therefore, the exposure from UV tanning appliances is likely to add to the well-known detrimental consequences of natural sun exposure, and there is no evidence to suggest that any type of sunbed is less harmful than natural sun exposure. Between two and three million non-melanoma skin cancers and approximately 132,000 malignant melanomas occur globally each year. One in every three cancers diagnosed worldwide is a skin cancer. In addition, estimates from WHO show that sun exposure may have been a key contributor to the development of cataracts in up to 20% of people who have cataracts.
Other factors that may cause users of sunbed to be more prone to adverse health effects include the following:
- Use of certain drugs and cosmetics during tanning
Some drugs, for example, anti-depressants, antibiotics, psoralens, antifungals, and antidiabetics, as well as some cosmetics, can make the skin more photosensitive and therefore decrease the time it takes for the skin to burn. Where there is a lack of trained staff or other methods of risk assessment, the potential for harm to the uninformed consumer is considerably greater.
- Dangers associated with childhood UV exposure
Childhood exposure to UV radiation is known to make an important contribution to the risk of developing melanoma later in life. For this reason, particular attention is required to ensure children do not use sunbeds. Hence, only adults above age of 18 are allowed to use sunbeds in Singapore.
The size of the skin area exposed
Modern “clam-type” tanning beds and canopies generally expose more of a person’s skin area to UV radiation than it would be in most outdoor situations under the sun, therefore health risk from tanning beds cannot be ignored.
While WHO does not recommend the use of UV sun tanning beds for cosmetic purposes, it is recognised that this equipment will continue to be available to the public. For this reason, there is a need for guidance to reduce the risks associated with their use.
People not suited to use UV sun tanning beds
According to the International Commission on Non-Ionizing Radiation Protection (ICNIRP), which is the international organization formally recognised by the WHO, people should not use artificial UV tanning devices if they:
- Have melano-compromised skin (skin phototypes I and II), i.e. their skin always sunburns with no ability to tan or has a high susceptibility to sunburn with only an ability to develop a light tan.
- Are less than 18 years of age.
- Have large numbers of moles.
- Tend to freckle.
- Have a history of frequent childhood sunburn.
- Have pre-malignant or malignant skin lesions.
- Have sun damaged skin.
- Are wearing cosmetics. This may enhance their sensitivity to UV exposure.
- Are taking medications. In this case they should seek advice from their physician to determine if the medication will make them UV radiation-sensitive.
Warning notices at establishment
In a commercial establishment, one or more notices, each with minimum dimensions of 21 cm x 30 cm (i.e. approximately A4 paper size) and presenting the following information in legible print, should be placed so it is within the immediate view of every client entering the establishment and in each sunbed cubicle:
- Exposure to ultraviolet radiation such as from a sunbed contributes to the skin ageing process and may cause skin cancer.
- People with skin that does not tan in natural sunlight should not use a sunbed.
- Intentional exposure to sunlight or sunbed should be avoided for 48 hours after sunbed exposure.
- UV radiation protective goggles must be worn at all times while undergoing sunbed exposure.
- No person under the age of 18 should use a sunbed.
Requirements for labelling of sunlamps
Under the Radiation Protection (Non-Ionising Radiation) Regulations, the requirements for labelling on the surface of the sunlamp include the following:
Each sunlamp shall have, on its external surface, a radiation warning sign that —
- is shown in 2 contrasting colours;
- has no outer dimensions less than 2 cm;
- is clearly visible and identifiable from the exposure position;
- bears the words “WARNING — ULTRAVIOLET RADIATION — FOLLOW INSTRUCTIONS — FAILURE TO USE PROTECTIVE EYEWEAR MAY RESULT IN SEVERE BURNS OR OTHER EYE INJURY — IF DISCOMFORT DEVELOPS, DISCONTINUE USE AND CONSULT A PHYSICIAN”; and
- incorporates a statement to indicate that —
i. as with natural sunlight, overexposure can cause eye injury and sunburn;
ii. repeated exposure may cause premature aging of skin and skin cancer;
iii. medications or cosmetics applied to the skin may increase sensitivity to ultraviolet light;
iv. a person who does not tan in the sun most likely will not tan from the use of this apparatus;
v. a person having a history of skin problems or having a specially sensitive skin to sunlight shall consult a physician before use;
vi. overexposure shall be avoided.