List Of Common UV Filters and Blockers

In recent years, there have been some controversy on chemical UV filters increasing cancer-causing free radicals, thus causing more damage than they prevent. In short, it meant that photo-unstable sunscreens may damage our skin. ie. Oxybenzone
Hence, simply applying sunscreen with ingredients like avobenzone, bemotrizinol, or benzophenone-3 (Oxybenzone) isn’t enough. Stabilizers are often needed to protect against ingredients that degrade easily. ie. in a sunscreen that uses avobenzone as a UV blocker, it may have octocrylene as a stabilizer. This increases the risk of irritation and adds to the low-level toxicity of the product.

Along with UV filters, its recommended to have an antioxidant to reduce the production of free radicals.

A sunscreen filter is photo-stable if it does not degrade in sunlight. In practice, the most photo-unstable filter is avobenzone. Octyl methoxycinnamate is also photo-unstable but it does not degrade quite as quickly. However, the combination of avobenzone and octinoxate degrades faster than either alone. Oxybenzone (benzophenone-3) is also photo-unstable.

You can also read more from EWG - The Trouble With Ingredients in Sunscreen.

List of Common UV filters and blockers

Chemical name: zinc oxide
UV spectrum: UVA-1 , UVA-2, UVB
type :physical
stability: stable
irritation : none
Pros: broad range protection, safe, anti-irritant
cons: white residue

Chemical name: titanium dioxide
UV spectrum: UVA-1, UVB
type: physical
stability: unstable
irritation: none
Pros: none
cons: insufficient protection against UVA-2, may generate free radicals,
white residue

Chemical name: phenylbenzimidazole sulfonic acid 
UV spectrum: UVB
type: chemical
stability: stable
irritation: low
Pros: may stabilize other chemicals, water soluble in salt form
cons: No UVA protection

Chemical name: homosalate
UV spectrum: UVB
type: chemical
stability: unstable
irritation: low
Pros: none
cons: No UVA protection, Poor range of UVB protection

Chemical name: octyl methoxycinnamate (octinoxate)
UV spectrum: UVB
type: chemical
stability: unstable (partially stabilized by bemotrizinol/ Tinosorb M)
irritation: potential high risk
Pros: none
cons: risk of possible estrogenic and other adverse effects

Chemical name: octyl salicylate (octisalate)
UV spectrum: UVB
type: chemical
stability: unstable
irritation: low
Pros: none
cons: Poor range of UVB protection

Chemical name: octocrylene
UV spectrum: UVB, UVA-2
type: chemical
stability: very stable, stabilizes other UV filters
irritation: low
Pros: very stable, stabilizes other UV filters
cons: weak, cannot be used alone

Chemical name: Benzophenone-3 (Oxybenzone)
UV spectrum: UVB, UVA-2
type: chemical
stability: unstable
irritation: high risk
Pros: none
cons: weak, cannot be used alone, promotes generation of free radicals,
systemically absorbed and excreted in urine at a much higher rate than
other sunscreen filters.

Chemical name: Avobenzone ( butyl methoxydibenzoylmethane, Parsol 1789, Eusolex 9020, Escalol 51)
UV spectrum: UVA-1, UVA-2
type: chemical
stability: unstable (Octocrylene, increases stability. Zinc oxide and
titanium dioxide reduce stability)
irritation: low
Pros: Full UVA protection
cons: loses effectiveness over time, may produce low-level
toxicity with long-term use

Chemical name: 4-Methylbenzylidene camphor , 4-MBC, 3-(4-Methylbenzylidene)
bornan-2-one , 3-(4-Methylbenzylidene)-dl-camphor
UV spectrum: UVB
type: chemical
stability: unstable
irritation: potential high risk
Pros: Stabilizes Avobenzone
cons:risk of possible estrogenic and other adverse effects, not approved in
the USA

Chemical name: Ecamsule/terephthalylidene dicamphor sulfonic acid (Mexoryl SX and XL)
UV spectrum: UVA-1, UVA-2
type: chemical
stability: stable
irritation: low
Pros: Ecamsule is acidic, the alkaline base used for neutralizing may cause
irritation for some people.
cons: Full UVA protection, photo-stable, expensive -patented by L’Oreal

Chemical name: Bisoctrizole/methylene bis-benzotriazolyl tetramethylbutylphenol (Tinosorb M, S)
UV spectrum: UVA-1, UVA-2, UVB
type: Chemical and Physical
stability: stable
irritation: low
Pros: Full UVA protection, photo-stable,pPartially stabilizes octinoxate
cons: Not approved in the USA