The Sunscreen Filter
excluding octinoxate and oxybenzone. The
first set of formulations contained avobenzone photostabilized by octocrylene, bemotrizinol and bisoctrizole. Formulation
A had a high SPF and B a moderate SPF.
The second set were formulated without
avobenzone (Formulations C and D) and
the third set was formulated with the inorganic particulates, zinc oxide and titanium dioxide (Formulations E and F). The
results are shown in Table IV.
1. Sunscreens with Avobenzone
We have stabilized avobenzone with
only the currently approved UVB ingredient octocrylene, and the potentially TEA
approved bemotrizinol and bisoctrizole.
Any restrictions of use of octocrylene
with avobenzone need to be observed.
The two UVA TEA ingredients offer photostability to avobenzone and SPFs of
50+ designation are easily achieved. The
Broad Spectrum protection, the Critical
Wavelength λc was 380 nm for the maximum SPF protection ( 51. 75) formulation
A and λ c was 378.3 nm for the moderate
SPF protection ( 28. 75) formulation B.
2. Sunscreens without Avobenzone
Our formulations clearly demonstrate
that with the use of the standard UVB
filters and the two TEA-UVA ingredients
(bemotrizinol and bisoctrizole), avobenzone is not required to achieve Broad
Spectrum protection. Excellent photostability is inherent in the ingredients themselves and medium to high SPFs can be
achieved. Formulation C had an SPF of
48. 38 and aλc of 379nm. Formulation D
had an SPF of 30. 88 and a λc of 378 nm.
3. Sunscreens with Inorganic
Several formulations were made with
combinations of zinc oxide and titanium
dioxide augmented by the two new TEA
UVA ingredients only. Extremely photo-
stable formulations with medium to high
SPF ( 50+) and broad spectrum protection
were achieved. Formulation E yielded an
SPF of 59. 4 and a λ c of 379nm, and for-
mulation F had an SPF of 28. 75 and aλc of
379nm. Note that bisoctrizole has a λmax
at 360nm (UVA-absorbance) with a criti-
cal wavelength λc of 388nm contributing
to significant broad spectrum protection.
Both ingredients are photo-stable broad
spectrum UVA filters and have been used
safely and effectively in Europe, Japan,
Australia and elsewhere for over a decade
already (see Table III).
In conclusion, the US sun care industry will benefit greatly from the approval
of the pending TEA ingredients, especially
the four UVA filters (L’Oréal’s ecamsule
and drometrizole trisiloxane, bemotrizinol and bisoctrizole). Once approved and
utilized by US cosmetic and sunscreen
manufacturers in their formulations, extremely photostable, broad spectrum
high SPF formulations would be possible. This would allow us to claim that
US sunscreens are not only on-par with
their European, Australian and Japanese
counterpart formulations but, with our
enhanced ingredients and technology, we
could be superior, the best and safest that
the world sunscreen industry can provide.
I would like to thank the staff of AMA Laboratories
(New City, NY) for its support in performing a two-
subject in-vivo SPF test and a Broad Spectrum Critical
Wavelength test for all these formulations. I would also
would like to thank my partner Tim Meadows for the
1. Nadim A. Shaath, “The Archaic TEA process
revisited” in The Sunscreen Filter, Happi, May edition
2. Nadim A. Shaath, “Ultraviolet Filters” in
Photochemical and Photobiological Sciences, Vol 9, pp
3. J. Nash and P. Tanner (2014), Photoderm.,
Photoimmun. And Photomed., Relevance of UV Filter/
sunscreen product photostability to human safety, 30,
4. Nadim A. Shaath, “The Sunscreen Innovation
Act”, The Sunscreen Filter, Happi, August Edition
8. Tests done at AMA Laboratories (New City,
NY). Formulations done at Shaath & Meadows
Consultation Laboratories (Florida).
TABLE IV: IN-VIVO/IN-VITRO TESTINg
RESULTS OF SUNSCREENS8
SPF (2 subjects) λc (Broad Spectrum Protection) Comments
A 51. 75 380 nm Maximum SPF protection with Avobenzone
B 26. 75 378.3 nm Moderate SPF protection with Avobenzone
C 48. 37 379 nm Maximum SPF protection without Avobenzone
D 30. 88 378 nm Moderate SPF protection without Avobenzone
E 59. 40 379 nm Maximum SPF protection with Inorganic Particulates
F 28. 75 379 nm Moderate SPF protection with Inorganic Particulates
Effective sunscreens from Europe may soon
spread to the US.