All about ‘sunscreens’
The term, ‘suntan’ lotion, may be commonly used by
many to describe a sunscreen product.
However, the purposeful use of a sunscreen product is to protect
you from the suns rays that cause a suntan.
This basic principal may help focus your view, on the roll of ‘sunscreens’,
for protection rather than to promote the idea of getting a suntan.
Protection
It is of course good advice to cover up, wear a hat, sit in the
shade or avoid the mid-day sun wherever possible, however, there
will be times when your skin is exposed to the sun and this is where
the use of sunscreens has an important roll to play.
Sunscreens, depending on their type, will absorb or reflect a proportion
of the suns UV rays. It is important to note that no ‘sunscreen’
will totally block all of the suns rays.
There are two types of rays that you will need protection from;
UVB and UVA. It is important to select a ‘sunscreen’
product that offers protection from both of these rays.
| UVB protection
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There is an internationally
recognised standard for the measurement of UVB absorbance, you
will recognise this by the SPF rating shown on all ‘sunscreen’
products. |
Important note: SPF ratings are only in relation to UVB
rays
Below is a diagram that demonstrates the absorbance levels of UVB
rays. The diagram shows the SPF category in accordance with the
percentage of absorbancy.
It is interesting to note that SPF 15 will absorb upto 93.33% of
UVB rays whereas
SPF 30 will only add a little over 3% greater absorption than SPF
15.
| UVA protection - |
There is no internationally recognised standard
for the measurement of UVA absorbance. |
However, here in the UK, we do have an Industry recognised standard;
the UVA star rating system. Most leading brands subscribe to this
system under license from Boots The Chemist Ltd, when selling their
products in the UK.
This can be recognised by the indication of a UVA star rating symbol,
normally shown on the reverse side of the product. These range from
one to five stars. Five star being the highest protection against
UVA.
This system includes a scientific test protocol that measures the
ratio of UVA/UVB absorbance for the sunscreen product. This is then
used to allocate the appropriate UVA star rating category.
In Australia they have a different system. This is called Australian
UV-A Standard.
Under this system there is also a scientific test protocol, this
may be described in broad terms as follows:-
UV-A protection is recognised when a sunscreen preparation transmits,
between a wavelength of 320nm and 360nm, less than 10% of the incoming
light.
In many other parts of the world, the term ‘broad-spectrum
UVA’ is generally used.
There is mounting pressure on Governments and the World Health
Organization to agree on an international standardised measurement
for the absorbance of UVA and to introduce a symbol or mark to be
easily identifiable by people, rather like the SPF rating used to
identify UVB protection.
Development of sunscreens & SPF ratings
We live in the 21st century, where technological advances are astounding.
We therefore expect both Governments and scientists to have all
the answers to all of our questions.
However, the development of ‘sunscreens’, their test
protocol and our in-depth knowledge of the dangers of the sun’s
UV rays are relatively new.
The advent of the package holiday and the desire to have a tanned
skin are relatively new in our times, especially in scientific terms,
where research takes on many different aspects and this can take
decades to prove findings.
The skin has an immediate response to overexposure to the sun.
Prolonged periods without protection will result in sunburn. This
is evident within a matter of hours. UVB rays are the culprits.
From this simplistic view you may understand that initially protection
from the sun’s UVB rays became a priority.
People are enjoying more outdoor activities, taking holidays in
hotter climates and ‘sunscreen’ products were originally
designed to protect you from sunburn. This gave birth to the ‘SPF
rating’ system which has an internationally agreed test protocol,
to determine the SPF values.
However, although sunburn is dangerous and can be seen immediately,
there are more dangerous aspects to overexposure, which take time
to take effect. This includes skin cancers and premature ageing
of the skin. Since skin has such an important job, to protect our
body from the harmful effects of the environment, premature ageing
is not merely a cosmetic look. Good healthy skin will protect the
body more efficiently.
Skin cancers usually result from the accumulative effect of overexposure
to UV light over a number of years. Many only appear in later life.
However, the most deadly and aggressive form of skin cancer –
melanoma – is found in young people. The incidence rate for
this cancer in young people is rising alarmingly.
There is mounting scientific research that UVA rays are now linked
to this disease, premature ageing of the skin and potentially other
forms of skin cancer.
This is why the World Health Organization is working to gain an
internationally agreed standard for the optimal method for specifying
protection against broad-spectrum UVA.
You may appreciate that although UVA sunscreens have been available
for a number of years, research into this field is more recent than
for UVB. The accumulative effect of overexposure is naturally more
recent than the initial sunburn effects. This is in a nutshell why
currently there is no internationally recognised ‘SPF’
type rating for UVA.
Important note:
We have explained earlier that in many countries the loose term
‘broad-spectrum UVA’ is generally used. When purchasing
products containing this term you will not know the level of protection
afforded by these products, only that it will contain some level
of UVA sunscreen. This may vary from country to country, and may
depend on their regulations.
You may consider it wise, to purchase your ‘sunscreen’
products before leaving the UK. In this way you can rely on the
star rating as your guide. We suggest products containing the five
star rating, as these will give the highest level of UVA protection.
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