Organic Sunscreen Actives

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Organic sunscreen actives are carbon based hence the name organic. They are also called chemical sunscreen actives. They work using a different mechanism than inorganic sunscreen actives to protect your skin from the UV rays. Organic sunscreen actives absorb UV radiation, dissipating it as heat, rather than deflect and block as do the inorganic sunscreen actives. Organic sunscreen actives are bothersome for some people causing irritation and allergic reactions. The inorganic sunscreens actives are a better choice if you are sensitive to the organics.

Here is a chart showing all of the organic sunscreen actives as well as the inorganic sunscreens (TiO2 and ZnO).  In addition, this chart shows the maximum concentrations allowed in a finished sunscreen product.

UV-filter	Other names	Maximum concentration	Permitted in these countries	Results of safety testing
p-Aminobenzoic acid	PABA	15% (EC- banned from sale to consumers from 8 October 2009)	USA, AUS	Protects against skin tumors in mice.[42][43][44] Shown to increase DNA defects, however, and is now less commonly used.
Padimate O	OD-PABA, octyldimethyl-PABA, σ-PABA	8% (EC,USA,AUS) 10% (JP) (Not currently supported in EU and may be delisted)	EC, USA, AUS, JP	Not tested
Phenylbenzimidazole sulfonic acid	Ensulizole, Eusolex 232, PBSA, Parsol HS	4% (US,AUS) 8% (EC) 3% (JP)	EC,USA, AUS, JP	Genotoxic in bacteria[45]
Cinoxate	2-Ethoxyethyl p-methoxycinnamate	3% (US) 6% (AUS)	USA, AUS	Not tested
Dioxybenzone	Benzophenone-8	3%	USA, AUS	Not tested
Oxybenzone	Benzophenone-3, Eusolex 4360, Escalol 567	6% (US) 10% (AUS,EU) 5% (JP)	EC, USA, AUS, JP	Not tested
Homosalate	Homomethyl salicylate, HMS	10% (EC, JP) 15% (US,AUS)	EC, USA, AUS, JP	Not tested
Menthyl anthranilate	Meradimate	5%	USA, AUS	Not tested
Octocrylene	Eusolex OCR, 2-Cyano-3,3-diphenyl acrylic acid, 2-ethylhexylester	10%	EC,USA, AUS, JP	Increases ROS[46]
Octyl methoxycinnamate	Octinoxate, EMC, OMC, Ethylhexyl methoxycinnamate, Escalol 557, 2-Ethylhexyl-paramethoxycinnamate, Parsol MCX	7.5% (US) 10% (EC,AUS)20% (JP)	EC,USA, AUS, JP
Octyl salicylate	Octisalate, 2-Ethylhexyl salicylate, Escalol 587,	5% (EC,USA,AUS) 10% (JP)	EC,USA, AUS, JP	Not tested
Sulisobenzone	2-Hydroxy-4-Methoxybenzophenone-5-sulfonic acid, 3-Benzoyl-4-hydroxy-6-methoxybenzenesulfonic acid, Benzophenone-4, Escalol 577	5% (EC) 10% (US, AUS, JP)	EC,USA, AUS, JP
Trolamine salicylate	Triethanolamine salicylate	12%	USA, AUS	Not tested
Avobenzone	1-(4-methoxyphenyl)-3-(4-tert-butyl phenyl)propane-1,3-dione, Butyl methoxy dibenzoylmethane, BMDBM, Parsol 1789, Eusolex 9020	3% (US) 5% (EC,AUS)10% (JP)	EC, USA, AUS, JP	Not available[47]
Ecamsule	Mexoryl SX, Terephthalylidene Dicamphor Sulfonic Acid	10%	EC,AUS (US:Approved in certain formulations up to 3% via New Drug Application (NDA) Route)	Protects against skin tumors in mice[48][49][50]
Titanium dioxide	CI77891	25% (No limit Japan)	EC,USA, AUS, JP	Not tested
Zinc oxide		25% (US) 20% (AUS) (EC-25% provided particle size >100 nm) (Japan, No Limit)	EC,USA, AUS, JP	Protects against skin tumors in mice[48]

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There are also several other sunscreen actives that are not approved for use in the US but are approved else where. Most of these sunscreen actives are for UVA protection. 

UV-filter	Other names	Maximum concentration	Permitted in
4-Methylbenzylidene camphor	Enzacamene, Parsol 5000, Eusolex 6300, MBC	4%*	EC, AUS
Tinosorb M	Bisoctrizole, Methylene Bis-Benzotriazolyl Tetramethylbutylphenol, MBBT	10%*	EC, AUS, JP
Tinosorb S	Bis-ethylhexyloxyphenol methoxyphenol triazine, Bemotrizinol, BEMT, anisotriazine	10% (EC, AUS) 3% (JP)*	EC, AUS, JP
Neo Heliopan AP	Bisdisulizole Disodium, Disodium phenyl dibenzimidazole tetrasulfonate, bisimidazylate, DPDT	10%	EC, AUS
Mexoryl XL	Drometrizole Trisiloxane	15%	EC, AUS
Benzophenone-9	Uvinul DS 49, CAS 3121-60-6, Sodium Dihydroxy Dimethoxy Disulfobenzophenone [53]	10%	JP
Uvinul T 150	Octyl triazone, ethylhexyl triazone, EHT	5% (EC, AUS) 3% (JP)*	EC, AUS
Uvinul A Plus	Diethylamino Hydroxybenzoyl Hexyl Benzoate	10% (EC,JP)	EC, JP
Uvasorb HEB	Iscotrizinol, Diethylhexyl butamido triazone, DBT	10% (EC) 5% (JP) *	EC, JP
Parsol SLX	Dimethico-diethylbenzalmalonate, Polysilicone-15	10%	EC, AUS, JP
Isopentenyl-4-methoxycinnamate	Isoamyl p-Methoxycinnamate, IMC, Neo Heliopan E1000, Amiloxate	10% *	EC, AUS

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Here is a chart showing the UVB and UVA protection ability of sunscreen actives. You will see that Zinc Oxide protects against both UVB and UVA radiation. 

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PABA is very irritating and is not used much anymore. In the USA, TiO2 and ZnO cannot be used with avobenzone. If you do work with avobenzone be aware that it can make the sunscreen yellow. TiO2 reacts with avobenzone and makes the formula yellow.