Dermatest newsletters

Our backcopy newsletters are available in pdf form for download.All contain scientific information relating to SPF and other skin product testing and relevant at the time of publication.

If you wish to subscribe to future newsletters please email us.

Latest News

12th Jan 2017

ISO 24444
– Review Gets Underway

This first ISO Sunscreen related document was
published in 2010 and has been re-opened for review during 2016. Up for review
after 5 years in use, this document will be modified with the primary objective
of improving reproducibility between test labs.
The changes are by no means finalized at this time,
but key issues being addressed are…

1. Dropping
of the use of Fitzpatrick prototyping as a basis for subject inclusion, and
instead rely solely upon Individual Tangent Angle (ITA0).

The ITA0 has been an option in the current version of ISO 24444. It
is an accurate objective measurement of skin colour based on use of a hand held
spectrophotometer. Each test subject can be assigned an ITA0, a
value that remains more or less the same over a period of time. Using this
classification, skin color becomes a continuum, rather than in three subjective
boxes according to the Fitzpatrick Scale.

2. Revision
of the definition of the MED for unprotected skin.
This value is not
quantified in the current ISO document. It is has been identified as a source of variability.

3. MEDs
to be reported in radiometric terms.
The objective here is to require that
test labs report results using exactly the same terminology.

4. Requiring
minimum unprotected MED radiometric doses
. We should all be using the same
exposure ranges based on ITA0 values if our Solar Simulators are to
as closely as possible imitate real sunlight.

5. Calibration
of radiometers for J/m2 erythema effective energy.
At present, it would
seem that this is the biggest source of variability between SPF values reported
by different test labs.

6. Possible
addition of new SPF 30 and 60 SPF reference standards
. Currently, two
Reference sunscreens with SPF around 15 are used as part of the internal
validation of the product application and measurement steps of the method.
Higher SPF references should help to further the qualification of this against
product samples in the High and Very High Protection ranges.

7. Addition
of photographs of the unprotected MEDs in the study reports for product testing
.
It is believed that this will assist in specification of the experimental
visual end point. The addition also includes a proposal for a new standardised scale
for scoring.

All of the above are provisional and subject to final agreement. The development of
the next version of the document will proceed during 2017 and is likely to be
published during 2018.