|Grade||Level of Evidence|
|A||Multiple double-blind, controlled clinical trials.|
|B||1 double-blind, controlled clinical trial.|
|C||At least 1 controlled or comparative clinical trial.|
|D||Uncontrolled, observational, animal or in-vitro studies only.|
|Grade||Effect||Size of Effect||Comments|
An excellent UVA absorber that absorbs in the entire UVA spectrum.
May help prevent skin wrinkling, since it inhibits the UVA-induced expression of collagen-degrading enzymes.
Looking to buy skin care products containing Avobenzone?
Buy from Amazon.com.
Table of contents:
Avobenzone is consistently one of the most common UV filters contained within personal care products, including skin care, facial makeup and lip care products. A survey of sunscreen products in Denmark in 2002 found that avobenzone was the second most frequently used UV filter, present in 44% of 75 products. More recent and more comprehensive surveys in the UK, Germany and Switzerland also agree that it is the most commonly included UV filter.
2. Skin penetration
Minimal skin penetration of sunscreens is desirable for maximal photoprotection and to prevent any possible local or systemic toxicity. Although a small amount (<1%) of topically applied avobenzone penetrated through baby mouse skin, avobenzone is not able to pass through human epidermis. It is however able to penetrate the stratum corneum and spread laterally to untreated areas of the skin.
One study has indicated that of the up to 16.8% of free avobenzone that can penetrate human skin, the majority is localized in the stratum corneum and the remainder in the epidermis. Another observed that avobenzone was located in the upper 30% of the stratum corneum 1 hour after application and did not reach the living cells. The absorption of avobenzone is not increased in photoaged skin.
Complexing avobenzone with cyclodextrins helps reduce its skin penetration flux, prolonging the absorption lag time. This can also lower the amount of avobenzone that accumulates in the epidermis as well as decrease transdermal penetration.
The vehicle, too, influences the skin penetration of avobenzone. Liposomes, lipid microparticles, and nanodelivery systems can aid in retaining avobenzone at the superficial layers of the skin.
3. Effects on the skin
In fact, avobenzone is among the best sunscreen agents for protecting against UVA radiation. An early study that evaluated 5 commercially available sunscreens in humans found that the product containing 3% avobenzone was the most effective. Avobenzone is also more effective than titanium dioxide, which effectively attenuates UVA wavelengths up to only 360 nm, and more effective than oxybenzone in both normal unsensitized and sensitized skin.
In a controlled in vivo study involving 10 human volunteers, a SPF 10 sunscreen containing avobenzone, enzacamene and ensulizole was successful in protecting against UVB-induced DNA damage as measured by the induction of cyclobutane thymine dimers.
Sunscreens containing avobenzone were also effective in photoprotecting patients with lupus erythematosus. However, a SPF-16 sunscreen containing avobenzone was not as effective as a SPF 40 sunscreen containing benzophenone in protecting patients with actinic reticuloid, despite having a higher protection value in the UVA range.
The addition of other sunscreen actives can improve the photoprotective efficacy of avobenzone. 2 separate studies on photosensitized subjects show that avobenzone + Padimate O provides greater protection than avobenzone alone, for instance. The bioconvertible antioxidants vitamin E acetate and sodium ascorbyl phosphate, too, improve photoprotection by converting to vitamin E and vitamin C within the skin, thereby forming an antioxidant reservoir that deactivates reactive oxygen species (ROS) generated by UV photons not blocked by the UV filters avobenzone and octinoxate.
The formulation influences the photoprotective effect of avobenzone as well. For example, avobenzone is retained better in the stratum corneum in an oil-in-water emulsion gel than in petrolatum, which helps enhance its photoprotective efficacy. Lipid nanoparticles loaded with avobenzone also demonstrated an enhanced UVA blocking effect compared to conventional emulsions, while other nanocarriers both enhanced and prolonged avobenzone's UV-protection efficacy. Complexation with cyclodextrins and poly(methyl methacrylate) (PMMA)-encapsulation also improves avobenzone's photoprotective ability.
However, incorporating avobenzone within lipid microparticles can adversely affect avobenzone's UV filter efficacy since it enhances the removal of avobenzone by watering.
3.2 Prevention of photoaging
UVA radiation is implicated in photoaging that avobenzone, as a UVA filter, may be able to prevent. In mice, topical avobenzone applied to the backs prior to UVA dosing reduced the induction of an elastin gene, indicating that it may inhibit solar elastosis, the accumulation of massive amounts of abnormal elastic tissue that is a major histopathologic change in the dermis of photoaged skin.
Avobenzone can also help prevent skin wrinkling caused by degradation of collagen fibres via inhibiting the UVA-induced expression of matrix metalloproteinase-1 (MMP-1). It was less efficacious than 2 experimental UVA filters as well as Uvinul A Plus in this respect, but more effective than Tinosorb S.
A commercial broad-spectrum sunscreen (Avène 50+) containing avobenzone, Tinosorb S, Tinosorb M and titanium dioxide dramatically reduced the UVA-induced expression of matrix-metalloproteinase (MMP)-1, MMP-3 and MMP-9 by 83%, 80% and 65% respectively in human keratinocytes, compared with the unprotected irradiated controls.
A full-UV spectrum absorbing cream containing avobenzone, octocrylene and Mexoryl SX applied to the UV-exposed buttock skin of human volunteers successfully prevented many biological changes associated with photoaging, including the darkening of the skin, the increase in skin dryness, the increased density and deepening of skin furrows, increases in stratum corneum and stratum granulosum thicknesses, the decrease in the expression of type I pro-collagen and the upregulation of matrix metalloproteinase-2 (MMP-2) expression.
3.3 Antioxidant effect
Whether avobenzone has antioxidative properties is debatable. It has been suggested that avobenzone can behave as a photoantioxidant or photoactivated antioxidant under conditions where its enol isomers can be accumulated. However, avobenzone failed to prevent the photooxidation of the fluorescent indicator 2,7-dichlorofluorescin (DCFH) when incorporated in liposomal membranes. Moreover, in human keratinocytes it did not minimize UVA-induced increases in oxidative stress and lipid peroxidation; on the contrary, it actually enhanced the levels of lipid hydroperoxides.
Avobenzone-induced lipid peroxidation can be reduced by the addition of antioxidants.
3.4 Other effects and uses
Sunscreen products containing avobenzone have demonstrated effectiveness in preventing polymorphic light eruptions (PMLE) in independent trials. One trial comparing the efficacy of a sunscreen cream containing avobenzone in combination with Mexoryl SX, octocrylene and titanium dioxide to a similar cream without avobenzone found that the former inhibted PMLE flares significantly better than the latter, proving that the inclusion of avobenzone provides clinical benefit.
In addition, an open-label study of a sunscreen combining avobenzone and Padimate O found that it reduced the cutaneous signs and symptoms of discoid lupus erythematosus or subacute cutaneous lupus erythematosus such as hyperpigmentation, papules, scaling, and erythema.
Upon sunlight irradiation, avobenzone tautomerises from the enol form to the keto form. The keto form is generated in a triplet excited state, which can interact with and damage key building blocks of biomolecules such as thymidine, tryptophan and tyrosine. Alternatively, the keto form can degrade, forming a photoproduct with strong absorption in the UVB region.
Avobenzone's photo-instability compromises its protection against UVA radiation. It has been reported that a cosmetic preparation containing avobenzone lost 85% of its UVA absorbance after 2 hours of sunlight exposure. This is consistent with another study showing that avobenzone in a cosmetic emulsion degraded chemically by about 60% after 1 hour and 90% after 4 hours of UV exposure.
The sensitivity of avobenzone to light is also dependent on the experimental conditions. Avobenzone is stable in polar solvents such as alcohol, but not in non-polar solvents.
It is important to note that some sunscreen actives are chemically incompatible with avobenzone and should be avoided or tested before their addition to a avobenzone-containing formulation. An example is octinoxate, which reacts with avobenzone under irradiation, leading to the destruction of both compounds and a loss of protection efficacy. The less frequently used UVB sunscreen active Padimate O has been put forward as another example.
Once incompatible ingredients are avoided, avobenzone can be photostabilized in a few ways. The presence of the sunscreen actives octocrylene and oxybenzone, believed to be efficient singlet and triplet quenchers respectively, can enhance the photostability of avobenzone. One study showed that the addition of 10% octocrylene kept the chemical structure of avobenzone virtually intact, and that 6% oxybenzone was able to maintain about 70% of the original concentration of avobenzone after 4 hours of UV irradiation. The UVB filters 4-methylbenzylidene camphor (MBC) and DOMBM, and the broad-spectrum UV absorber Tinosorb S are also effective. The combination of 5% octisalate + 12% homosalate was less effective, but still provided modest benefit.
Manganese-doped titanium dioxide can also stabilize avobenzone and the avobenzone + octinoxate combination. Similarly, the antioxidant quercetin has been found to significantly reduce the photodegradation of avobenzone and octinoxate. Quenching agents such as DEHN, DESM, polycrylene and diethylhexyl 2,6-naphthalate can serve as photostabilizers as well.
Avobenzone's photostability can also be improved by encapsulation within poly(methyl methacrylate) (PMMA), lipospheres and nanocarriers, or through complexation with cyclodextrins.
Avobenzone is approved by the US FDA as an active ingredient in sunscreens up to a concentration of 3%. It is also an approved UV filter under the EU Cosmetics Directive, which stipulates a maximum concentration of 5%.
5.1 Possible skin toxicity
Avobenzone displayed a pronounced, UVA dose-dependent phototoxicity in the 3T3 Neutral Red Uptake Phototoxicity Test. This agrees with the results of another in vitro experiment using cultured human keratinocytes, which found changes in cell morphology and proliferation as evidence of toxicity. The poor penetration of avobenzone into human skin means that its concentration in the viable epidermis after topical application is probably several times lower than that required to induce toxicity however.
The triplet excited state of the keto form that is generated upon irradiation of avobenzone can interact with and damage key building blocks of biomolecules such as thymidine, tryptophan and tyrosine. This helps explain the observations of earlier studies in which avobenzone was found to induce the production of free radicals and to cause DNA and protein damage. Fortunately, these adverse effects can be inhibted by adding triplet quenchers and free radical scavengers to formulations containing avobenzone or by complexing it with hydroxypropyl-beta-cyclodextrin (HP-beta-CD).
Avobenzone does not appear to be photomutagenic however, as its presence in irradiated Chinese hamster ovary cells did not cause a significant increase in UV-induced chromosomal aberrations.
5.2 Photoallergic contact dermatitis
Even though photoallergic reactions to UV filters are considered rare in general, there are numerous reports in the medical literature of photoallergic contact dermatitis caused by avobenzone.
In fact, avobenzone is one of the most common UV filter photoallergens. A 1998 review of 7 years' data from Swedish dermatology clinics showed that of 34 allergic reactions originating from photocontact, 6 (18%) were caused by avobenzone. Similarly, a more recent photopatch test study in Europe conducted on 1031 patients with suspected photoallergic contact dermatitis revealed that avobenzone, octocrylene and oxybenzone were the most frequent elicitors among the organic UV absorbers.
It has been suggested that these photocontact allergies are due to the arylglyoxals that are formed upon photodegradation of avobenzone, since they are strong sensitizers in the murine local lymph node assay as well as highly reactive toward the nucleophile arginine, which indicates that the immunogenic hapten-protein complex could be formed via an electrophilic-nucleophilic pathway.
Curiously, the addition of avobenzone to topical formulations of the NSAID ketoprofen appears to be effective in inhibiting ketoprofen contact dermatitis.
5.3 No evidence of estrogenicity
Unlike oxybenzone, homosalate, octinoxate, Padimate O and 4-methyl-benzylidene camphor (4-MBC), avobenzone did not stimulate the proliferation of human breast cancer cells in vitro nor did it increase the uterine weights of rats in an uterotrophic assay, indicating that it is does not possess estrogenic activity.
- Kockler J, et. al. Butyl methoxy dibenzoylmethane. Profiles Drug Subst Excip Relat Methodol. (2013)
- Beasley DG, Meyer TA. Characterization of the UVA protection provided by avobenzone, zinc oxide, and titanium dioxide in broad-spectrum sunscreen products. Am J Clin Dermatol. (2010)
- Rastogi SC. UV filters in sunscreen products--a survey. Contact Dermatitis. (2002)
- Kerr AC. A survey of the availability of sunscreen filters in the UK. Clin Exp Dermatol. (2011)
- Uter W, et. al. Coupled exposure to ingredients of cosmetic products: III. Ultraviolet filters. Contact Dermatitis. (2014)
- Manová E, et. al. Organic UV filters in personal care products in Switzerland: a survey of occurrence and concentrations. Int J Hyg Environ Health. (2013)
- Montenegro L, Paolino D, Puglisi G. Effects of silicone emulsifiers on in vitro skin permeation of sunscreens from cosmetic emulsions. J Cosmet Sci. (2004)
- Klinubol P, et. al. Transdermal penetration of UV filters. Skin Pharmacol Physiol. (2008)
- Jiang R, et. al. Absorption of sunscreens across human skin: an evaluation of commercial products for children and adults. Br J Clin Pharmacol. (1999)
- Hayden CG, et. al. Sunscreen penetration of human skin and related keratinocyte toxicity after topical application. Skin Pharmacol Physiol. (2005)
- Chatelain E, Gabard B, Surber C. Skin penetration and sun protection factor of five UV filters: effect of the vehicle. Skin Pharmacol Appl Skin Physiol. (2003)
- Jacobi U, et. al. Pathways of lateral spreading. Skin Pharmacol Physiol. (2011)
- Simeoni S, Scalia S, Benson HA. Influence of cyclodextrins on in vitro human skin absorption of the sunscreen, butyl-methoxydibenzoylmethane. Int J Pharm. (2004)
- Lademann J, et. al. The tape stripping procedure--evaluation of some critical parameters. Eur J Pharm Biopharm. (2009)
- Hung CF, et. al. The risk of hydroquinone and sunscreen over-absorption via photodamaged skin is not greater in senescent skin as compared to young skin: Nude mouse as an animal model. Int J Pharm. (2014)
- Shokri J, et. al. The effect of Beta-cyclodextrin on percutaneous absorption of commonly used Eusolex® sunscreens. Drug Res (Stuttg). (2013)
- Yang J, et. al. Influence of hydroxypropyl-beta-cyclodextrin on transdermal penetration and photostability of avobenzone. Eur J Pharm Biopharm. (2008)
- Montenegro L, Puglisi G. Evaluation of sunscreen safety by in vitro skin permeation studies: effects of vehicle composition. Pharmazie. (2013)
- Liu JJ, et. al. Preparation and characterization of cosmeceutical liposomes loaded with avobenzone and arbutin. J Cosmet Sci. (2013)
- Scalia S, Coppi G, Iannuccelli V. Microencapsulation of a cyclodextrin complex of the UV filter, butyl methoxydibenzoylmethane: in vivo skin penetration studies. J Pharm Biomed Anal. (2011)
- Scalia S, Mezzena M, Ramaccini D. Encapsulation of the UV filters ethylhexyl methoxycinnamate and butyl methoxydibenzoylmethane in lipid microparticles: effect on in vivo human skin permeation. Skin Pharmacol Physiol. (2011)
- Iannuccelli V, et. al. In vivo and in vitro skin permeation of butyl methoxydibenzoylmethane from lipospheres. Skin Pharmacol Physiol. (2008)
- Hanno I, Anselmi C, Bouchemal K. Polyamide nanocapsules and nano-emulsions containing Parsol® MCX and Parsol® 1789: in vitro release, ex vivo skin penetration and photo-stability studies. Pharm Res. (2012)
- Puglia C, et. al. Evaluation of nanostructured lipid carriers (NLC) and nanoemulsions as carriers for UV-filters: characterization, in vitro penetration and photostability studies. Eur J Pharm Sci. (2014)
- Vielhaber G, et. al. Sunscreens with an absorption maximum of greater than or equal to 360 nm provide optimal protection against UVA1-induced expression of matrix metalloproteinase-1, interleukin-1, and interleukin-6 in human dermal fibroblasts. Photochem Photobiol Sci. (2006)
- Leenutaphong V. Evaluating the UVA protection of commercially available sunscreens. J Med Assoc Thai. (1992)
- Kaidbey K, Gange RW. Comparison of methods for assessing photoprotection against ultraviolet A in vivo. J Am Acad Dermatol. (1987)
- van Praag MC, et. al. Determination of the photoprotective efficacy of a topical sunscreen against UVB-induced DNA damage in human epidermis. J Photochem Photobiol B. (1993)
- Callen JP, et. al. Safety and efficacy of a broad-spectrum sunscreen in patients with discoid or subacute cutaneous lupus erythematosus. Cutis. (1991)
- Stege H, et. al. Evaluation of the capacity of sunscreens to photoprotect lupus erythematosus patients by employing the photoprovocation test. Photodermatol Photoimmunol Photomed. (2000)
- Greaves K, Cripps AJ, Cripps DJ. Actinic reticuloid: action spectra and UVA protection factor sunscreens. Clin Exp Dermatol. (1992)
- Gange RW, et. al. Efficacy of a sunscreen containing butyl methoxydibenzoylmethane against ultraviolet A radiation in photosensitized subjects. J Am Acad Dermatol. (1986)
- Lowe NJ, et. al. Indoor and outdoor efficacy testing of a broad-spectrum sunscreen against ultraviolet A radiation in psoralen-sensitized subjects. J Am Acad Dermatol. (1987)
- Hanson KM, Clegg RM. Bioconvertible vitamin antioxidants improve sunscreen photoprotection against UV-induced reactive oxygen species. J Cosmet Sci. (2003)
- Niculae G, et. al. Lipid nanoparticles based on butyl-methoxydibenzoylmethane: in vitro UVA blocking effect. Nanotechnology. (2012)
- Niculae G, et. al. Coencapsulation of butyl-methoxydibenzoylmethane and octocrylene into lipid nanocarriers: UV performance, photostability and in vitro release. Photochem Photobiol. (2013)
- Wu PS, et. al. Effects of the novel poly(methyl methacrylate) (PMMA)-encapsulated organic ultraviolet (UV) filters on the UV absorbance and in vitro sun protection factor (SPF). J Photochem Photobiol B. (2014)
- Trotta V, et. al. Influence of lipid microparticle encapsulation on in vitro efficacy, photostability and water resistance of the sunscreen agents, octyl methoxycinnamate and butyl methoxydibenzoylmethane. Drug Dev Ind Pharm. (2013)
- Sander CS, et. al. Photoaging is associated with protein oxidation in human skin in vivo. J Invest Dermatol. (2002)
- Schroeder P, et. al. Partial depletion of mitochondrial DNA from human skin fibroblasts induces a gene expression profile reminiscent of photoaged skin. J Invest Dermatol. (2008)
- Takeuchi T, Uitto J, Bernstein EF. A novel in vivo model for evaluating agents that protect against ultraviolet A-induced photoaging. J Invest Dermatol. (1998)
- Bernstein EF, et. al. Enhanced elastin and fibrillin gene expression in chronically photodamaged skin. J Invest Dermatol. (1994)
- Jean C, et. al. UVA-activated synthesis of metalloproteinases 1, 3 and 9 is prevented by a broad-spectrum sunscreen. Photodermatol Photoimmunol Photomed. (2011)
- Seité S, et. al. A full-UV spectrum absorbing daily use cream protects human skin against biological changes occurring in photoaging. Photodermatol Photoimmunol Photomed. (2000)
- Aspée A, Aliaga C, Scaiano JC. Transient enol isomers of dibenzoylmethane and avobenzone as efficient hydrogen donors toward a nitroxide pre-fluorescent probe. Photochem Photobiol. (2007)
- Tran C, et. al. A new model using liposomes that allow to distinguish between absorption and oxidative properties of sunscreens. Photochem Photobiol. (2002)
- Armeni T, et. al. Lack of in vitro protection by a common sunscreen ingredient on UVA-induced cytotoxicity in keratinocytes. Toxicology. (2004)
- Damiani E, et. al. Synthesis and application of a novel sunscreen-antioxidant. Free Radic Res. (2006)
- Fusaro RM, Johnson JA. Topical photoprotection for hereditary polymorphic light eruption of American Indians. J Am Acad Dermatol. (1991)
- Schleyer V, et. al. Prevention of polymorphic light eruption with a sunscreen of very high protection level against UVB and UVA radiation under standardized photodiagnostic conditions. Acta Derm Venereol. (2008)
- DeLeo VA, et. al. A new ecamsule-containing SPF 40 sunscreen cream for the prevention of polymorphous light eruption: a double-blind, randomized, controlled study in maximized outdoor conditions. Cutis. (2009)
- Pinto da Silva L, et. al. Structural, energetic, and UV-Vis spectral analysis of UVA filter 4-tert-butyl-4'-methoxydibenzoylmethane. J Phys Chem B. (2014)
- Paris C, et. al. A blocked diketo form of avobenzone: photostability, photosensitizing properties and triplet quenching by a triazine-derived UVB-filter. Photochem Photobiol. (2009)
- Cantrell A, McGarvey DJ. Photochemical studies of 4-tert-butyl-4'-methoxydibenzoylmethane (BM-DBM). J Photochem Photobiol B. (2001)
- Tarras-Wahlberg N, et. al. Changes in ultraviolet absorption of sunscreens after ultraviolet irradiation. J Invest Dermatol. (1999)
- Wetz F, et. al. A new long-chain UV absorber derived from 4-tert-butyl-4'-methoxydibenzoylmethane: absorbance stability under solar irradiation. J Cosmet Sci. (2005)
- Huong SP, et. al. Photoreactivity of the sunscreen butylmethoxydibenzoylmethane (DBM) under various experimental conditions. J Photochem Photobiol A. (2008)
- Sayre RM, et. al. Unexpected photolysis of the sunscreen octinoxate in the presence of the sunscreen avobenzone. Photochem Photobiol. (2005)
- Dondi D, Albini A, Serpone N. Interactions between different solar UVB/UVA filters contained in commercial suncreams and consequent loss of UV protection. Photochem Photobiol Sci. (2006)
- Diffey BL, et. al. Suncare product photostability: a key parameter for a more realistic in vitro efficacy evaluation. Eur J Dermatol. (1997)
- Bonda CA. Research pathways to photostable sunscreens. Cosmet Toil. (2008)
- Gaspar LR, Maia Campos PM. Evaluation of the photostability of different UV filter combinations in a sunscreen. Int J Pharm. (2006)
- Scalia S, Mezzena M. Incorporation in lipid microparticles of the UVA filter, butyl methoxydibenzoylmethane combined with the UVB filter, octocrylene: effect on photostability. AAPS PharmSciTech. (2009)
- Scalia S, Mezzena M. Co-loading of a photostabilizer with the sunscreen agent, butyl methoxydibenzoylmethane in solid lipid microparticles. Drug Dev Ind Pharm. (2009)
- Oguchi-Fujiyama N, et. al. Photophysical properties of dioctyl 4-methoxybenzylidenemalonate: UV-B absorber. Photochem Photobiol Sci. (2012)
- Chatelain E, Gabard B. Photostabilization of butyl methoxydibenzoylmethane (Avobenzone) and ethylhexyl methoxycinnamate by bis-ethylhexyloxyphenol methoxyphenyl triazine (Tinosorb S), a new UV broadband filter. Photochem Photobiol. (2001)
- Wakefield G, et. al. The effects of manganese doping on UVA absorption and free radical generation of micronised titanium dioxide and its consequences for the photostability of UVA absorbing organic sunscreen components. Photochem Photobiol Sci. (2004)
- Wakefield G, Stott J. Photostabilization of organic UV-absorbing and anti-oxidant cosmetic components in formulations containing micronized manganese-doped titanium oxide. J Cosmet Sci. (2006)
- Scalia S, Mezzena M. Photostabilization effect of quercetin on the UV filter combination, butyl methoxydibenzoylmethane-octyl methoxycinnamate. Photochem Photobiol. (2010)
- Bonda C, Steinberg D. A new photostabilizer for full spectrum sunscreens. Cosmet Toil. (2000)
- Chaudhuri RK, et. al. Design of a photostabilizer having built-in antioxidant functionality and its utility in obtaining broad-spectrum sunscreen formulations. Photochem Photobiol. (2006)
- Lhiaubet-Vallet V, et. al. Filter-filter interactions. Photostabilization, triplet quenching and reactivity with singlet oxygen. Photochem Photobiol Sci. (2010)
- Benevenuto CG, et. al. Influence of the photostabilizer in the photoprotective effects of a formulation containing UV-filters and vitamin A. Photochem Photobiol. (2010)
- Iannuccelli V, et. al. Influence of liposphere preparation on butyl-methoxydibenzoylmethane photostability. Eur J Pharm Biopharm. (2006)
- Scalia S, et. al. Encapsulation in lipospheres of the complex between butyl methoxydibenzoylmethane and hydroxypropyl-beta-cyclodextrin. Int J Pharm. (2006)
- US Food and Drug Administration. CFR - Code of Federal Regulations Title 21, Part 352, Subpart B, Section 352.10. Code of Federal Regulations. (2013)
- European Commission. List of UV filters allowed in cosmetic products. Cosmetics Directive. (2011)
- Gaspar LR, et. al. Skin phototoxicity of cosmetic formulations containing photounstable and photostable UV-filters and vitamin A palmitate. Toxicol In Vitro. (2013)
- Damiani E, et. al. Nitroxide radicals protect DNA from damage when illuminated in vitro in the presence of dibenzoylmethane and a common sunscreen ingredient. Free Radic Biol Med. (1999)
- Damiani E, et. al. Increased oxidative modification of albumin when illuminated in vitro in the presence of a common sunscreen ingredient: protection by nitroxide radicals. Free Radic Biol Med. (2000)
- Scalia S, et. al. Influence of hydroxypropyl-beta-cyclodextrin on photo-induced free radical production by the sunscreen agent, butyl-methoxydibenzoylmethane. J Pharm Pharmacol. (2002)
- Chételat A, Dresp JH, Gocke E. Photomutagenesis test development: II. 8-Methoxypsoralen, chlorpromazine and sunscreen compounds in chromosomal aberration assays using CHO cells. Mutat Res. (1993)
- Darvay A, et. al. Photoallergic contact dermatitis is uncommon. Br J Dermatol. (2001)
- Shaw T, et. al. True photoallergy to sunscreens is rare despite popular belief. Dermatitis. (2010)
- Schauder S, Ippen H. Photoallergic and allergic contact dermatitis from dibenzoylmethanes. Photodermatol. (1986)
- de Groot AC, Weyland JW. Contact allergy to butyl methoxydibenzoylmethane. Contact Dermatitis. (1987)
- English JS, White IR, Cronin E. Sensitivity to sunscreens. Contact Dermatitis. (1987)
- Motley RJ, Reynolds AJ. Photocontact dermatitis due to isopropyl and butyl methoxy dibenzoylmethanes (Eusolex 8020 and Parsol 1789). Contact Dermatitis. (1989)
- Buckley DA, et. al. Contact and photocontact allergy to dibenzoylmethanes and contact allergy to methylbenzylidene camphor. Contact Dermatitis. (1993)
- Parry EJ, Bilsland D, Morley WN. Photocontact allergy to 4-tert.butyl-4'-methoxy-dibenzoylmethane (Parsol 1789). Contact Dermatitis. (1995)
- Stitt WZ, et. al. Multiple chemical sensitivities, including iatrogenic allergic contact dermatitis, in a patient with chronic actinic dermatitis: implications for management. Am J Contact Dermat. (1996)
- Schmidt T, Ring J, Abeck D. Photoallergic contact dermatitis due to combined UVB (4-methylbenzylidene camphor/octyl methoxycinnamate) and UVA (benzophenone-3/butyl methoxydibenzoylmethane) absorber sensitization. Dermatology. (1998)
- Collaris EJ, Frank J. Photoallergic contact dermatitis caused by ultraviolet filters in different sunscreens. Int J Dermatol. (2008)
- Beach RA, Pratt MD. Chronic actinic dermatitis: clinical cases, diagnostic workup, and therapeutic management. J Cutan Med Surg. (2009)
- Berne B, Ros AM. 7 years experience of photopatch testing with sunscreen allergens in Sweden. Contact Dermatitis. (1998)
- European Multicentre Photopatch Test Study (EMCPPTS) Taskforce. A European multicentre photopatch test study. Br J Dermatol. (2012)
- Karlsson I, et. al. Photodegradation of dibenzoylmethanes: potential cause of photocontact allergy to sunscreens. Chem Res Toxicol. (2009)
- Atarashi K, et. al. Addition of UVA-absorber butyl methoxy dibenzoylmethane to topical ketoprofen formulation reduces ketoprofen-photoallergic reaction. J Photochem Photobiol B. (2012)
- Schlumpf M, et. al. In vitro and in vivo estrogenicity of UV screens. Environ Health Perspect. (2001)