Active Sunscreen Research Articles

Synthesis, Characterization, and Optical Properties of Novel Heterocyclic Azo Dyes and Evaluation of Their Antioxidant Activity as an Active Sunscreen Agent

AbstractWe synthesized some novel isoxazole azo derivatives using conventional methods and studied their linear, non‐linear optical properties and antioxidant activity. UV‐Vis spectroscopy revealed absorption bands ranging from 310–470 nm for the obtained compounds. Compounds 3 c and 3 b, for example, showed a large redshift and solvatochromic behavior. NLO analysis results show that compounds exhibit a greater NLO response than the magnitude of urea done by the DFT method. The electrochemical properties of compounds are studied using cyclic voltammetry and results are used for calculation of HOMO and LUMO experimentally. The antioxidant activity of the synthesized azo dyes displayed that 3 c has excellent antioxidant activity with the highest percentage (71.54605 %) of radical inhibition as compared to reference standard Vit‐C. Molecular docking analysis shows that compounds have a strong binding affinity in the range of −7.0 to −4.6 kcal/mol compared to Vit‐C, which has a binding affinity of −3.6 kcal/mol. The sun protection factor performance was determined by UV‐Vis spectroscopy, and results show that compounds are most effective, exhibit a remarkable SPF value, and offer superior sun protection by absorbing UV rays.

Molecularly engineered lignin to polyphenol via organocatalysis as an active sunscreen ingredient

Phenolation is one of the effective strategies to synthesize lignin-based polyphenols, improve lignin's properties, and extend its value-added applications in biological, medicinal and cosmetic fields. Herein, by taking the structural feature advantage of lignin, an effective and green strategy was developed to molecularly engineer lignin into a robust lignin-3-(2-hydroxyphenyl)propionate ester (LPPE) derivative via a transesterification reaction between 3,4-dihydrocoumarin (DHC) and the aliphatic hydroxyls in lignin under organocatalysis. The strategy is optimized and the novel derivative was systematically characterized by 1H, 13C and 31P nuclear magnetic resonance (NMR) and Fourier transform infrared (FT-IR) spectroscopy. The findings indicated that the successful introduction of 3-(2-hydroxyphenyl)propionate groups using a OH groups/DHC/organic base molar ratio of 1꞉1꞉0.3 at 120 °C for 6 h increased the content of phenolic hydroxyl groups from 1.793 1 to 3.017 9 mmol/g, and the LPPE exhibited excellent ultraviolet-absorbing and antioxidant performance with up to 90% free radical scavenging activity within 20 min using 5 mg/mL of LPPE. In addition, good biocompatibility and a high Sun protection factor (SPF) value of 40.9 were achieved at 5% (w) dosage of LPPE in the cream, indicating its significant application potential in sunscreen.

Developing Safe Organohydrogel Sunscreens Using Polyelectrolyte-Betaine Surfactant Complexes.

Oil-in-water emulsions are extensively used in skincare products due to their improved texture, stability, and effectiveness. There is limited success in developing effective delivery systems that can selectively target the active sunscreen ingredients onto the skin surface. Herein, an organohydrogel was prepared by physical cross-linking of an oil-in-water nanoemulsion with chitosan under neutral pH conditions. In the presence of a small quantity of coconut oil, lauramidopropyl betaine and glycerol were able to emulsify the active sunscreen ingredients into nanoscale droplets with enhanced ultraviolet light absorption. A facile pH-triggered interfacial cross-linking approach was applied to transform the nanoemulsion into an organohydrogel sunscreen. Furthermore, the organohydrogel sunscreen displayed encouraging characteristics including efficient UV-blocking capacity, resistance to water, simple removal, and minimal skin penetration. This facile approach provides an effective pathway for scaling up the organohydrogels, which are highly suitable for the safe application of sunscreen.

Oxybenzone-loaded Polymeric Nanocapsule Gel: Strategy to Reduce Skin Penetration and Drug-induced Irritation

Aim: This work aimed to determine whether the oxybenzone-loaded nanocapsule gel (NC gel) can reduce the degree of skin penetration and, thereby, the skin irritation caused by the drug. Background: Sunscreens must be retained on the uppermost skin surface, forming a protective film throughout the entire UV exposure period. Skin penetration and/or light-induced decomposition of sunscreens is undesirable as this would decrease the expected UV protection. The changes in colour and appearance of the sunscreen, as well as the possible increase in the phototoxicity and allergenic potential of sunscreen breakdown products, are also of concern. : Furthermore, exposure to UVB radiation leads to impairment in the stratum corneum and hence enhances the skin's penetration of sunscreen actives, leading to systemic absorption. Currently, available sunscreen agents are low-molecular-weight lipophilic molecules, which make them capable of penetrating the skin and being systemically absorbed. : Oxybenzone is an organic compound widely used in commercial sunscreen preparations. The low molecular weight and lipophilic nature of oxybenzone facilitate penetration through the stratum corneum, leading to irritation and allergic reactions. : Polymeric nanocapsules (NCs) have been developed to ensure a controlled release of pharmaceutical and cosmetic agents and/or exert a preventive effect against the harmful side effects induced by direct contact of tissues with high amounts of the drug. Hence, we hypothesised that encapsulating the oxybenzone polymeric nanocapsule system would reduce the irritation and its allergic potential upon topical application. Objective: The current study aimed to develop a polymeric nanocapsule-based gel of oxybenzone and investigate its skin deposition by ex vivo permeation studies. Methods: The polymeric nanocapsules were prepared by the solvent displacement method using a combination of Eudragit RSPO and Eudragit RLPO polymers. Further nanocapsules were incorpo-rated into the xanthan gum gel base. It was evaluated for particle size, PDI, zeta potential, drug con-tent, in vitro release, ex vivo permeation, sunscreen efficacy and skin irritation potential by the HET CAM test. Results: Particle size, PDI, zeta potential, percent encapsulation, and loading of drug-loaded nanocap-sule suspension were found to be 237.1 nm, 0.189 + 58.4 mV, 852 + 0.5%, and 19.45 + 0.94%, re-spectively. DSC results indicate the suitability of selected excipients. In vitro release studies indicated 68.99% oxybenzone release from NC suspension, while NC gel showed 58.87% at the end of 24 hrs. Ex vivo permeation results showed significantly higher drug permeation from plain oxybenzone gel than NC gel. Permeation flux and reduction ratio suggest a three-fold reduction in skin permeation by NC gel. The gel offered medium-level sun protection with an SPF value of 22.12. According to the HET CAM study, there was no evidence of skin irritation caused by NC gel. Conclusion: It is concluded that the encapsulation of oxybenzone prevents direct interaction with the skin, reducing the chances of skin irritation and penetration. Results suggest that nanocapsules in gel bases can provide a promising formula for safer topical delivery of sunscreen.

Rational Design and Synthesis of Lignin‐Derived Smart Sunscreens

AbstractLignin exhibits a long‐active UV‐blocking property due to its macromolecular aromatic structure and unique semiquione‐quione‐hydroquione transition. However, its poor absorbance in UVA region (320–400 nm) and irregular aggregation are still the obstacles. Herein, active spirapyrane (SP‐Br) is synthesized and covalently introduced into alkali lignin (AL) to construct photo‐stimulated UV‐absorbing enhancement sunscreen actives (AL‐SPn). The introduction of SP significantly improved the absorbance of AL in UVA region and its aggregation is effectively eased. When the optimal AL‐SP3 solution is exposed to UV irradiation, the color turned purple, and the absorbance in UVA region further improved as the unconjugated SP transformed into conjugated merocyanine (MC) structure. When the light is removed, the solution recovered light yellow. The antioxidant property of AL endow the reversible SP‐MC transformation with good cyclic stability. As‐prepared AL‐SP3 based sunscreen exhibit obvious photo‐stimulated enhancement effect. The sun protection factor (SPF) improved from 23 to 89 after 4 h irradiation, and can maintain the high performance for another 8 h. In addition, it exhibit low permeation and good biocompatibily in vitro and vivo, demonstrating its good potential in practical use.

Review on photoprotection: a clinician's guide to the ingredients, characteristics, adverse effects, and disease-specific benefits of chemical and physical sunscreen compounds.

Photoprotection is a critical health prevention strategy to reduce the deleterious effects of ultraviolet radiation (UVR) and visible light (VL). Methods of photoprotection are reviewed in this paper, with an emphasis on sunscreen. The most appropriate sunscreen formulation for personal use depends on several factors. Active sunscreen ingredients vary in their protective effect over the UVR and VL spectrum. There are dermatologic diseases that cause photosensitivity or that are aggravated by a particular action spectrum. In these situations, sunscreen suggestions can address the specific concern. Sunscreen does not represent a single entity. Appropriate personalized sunscreen selection is critical to improve compliance and clinical outcomes. Health care providers can facilitate informed product selection with awareness of evolving sunscreen formulations and counseling patients on appropriate use. This review aims to summarize different forms of photoprotection, discuss absorption of sunscreen ingredients, possible adverse effects, and disease-specific preferences for chemical, physical or oral agents that may decrease UVR and VL harmful effects.

34428 Clinical and biophysical assessment of the effects of daily use of a nature-based, broad-spectrum mineral sunscreen containing bakuchiol in photoaged skin

Background: Skin exposure to ultraviolet radiation causes disruption of fibroblast-extracellular matrix interactions causing loss of/damage to collagen, decreased fibroblast cell density and morphology and degeneration of the elastic fiber network. These result in clinical degenerative changes such as wrinkles, sallow complexion and loss of hydration and elasticity. We developed a photostable, broad-spectrum SPF 30 product with inorganic sunscreen actives and a natural retinol alternative, bakuchiol. Objective: To investigate the effects of a nature-based mineral broad-spectrum sunscreen to improve clinical outcomes of photodamaged skin. Methods: A single-center, open-label study was performed on 49 female subjects aged 35 to 60 years with mild to moderate signs of photodamage. Evaluations of the nature-based sunscreen product were made at baseline and at week 6 after twice daily minimum topical application on the face. The dermatologist investigator and subjects assessed efficacy and tolerability using a 5-point ordinal scale (0 = none, 4 = severe). Noninvasive measurements of skin hydration, barrier function and elasticity were conducted. Results: Investigator clinical evaluations showed significant improvements in skin laxity, fine lines, smoothness, pigmentation, and texture. Subject-rated change from baseline demonstrated similar efficacy as the investigator. Skin hydration significantly improved by 21%. A significant 32% decrease in the retraction time (ms) was measured after 6 weeks of product use, indicating improved skin elasticity. There was no disruption to skin barrier function. No tolerability related issues were observed during study duration. Conclusion: Daily photoprotection using a nature-based broad-spectrum mineral sunscreen containing bakuchiol visibly improved the signs of photodamage and the skin’s biophysical properties.

Computational Study Potency of Eugenol and Safrole Derivatives as Active Sunscreen Material

Computational studies have been carried out on eugenol and safrole derivatives as active sunscreen materials. The calculations were using Density Functional Theory (DFT) with the B3LYP functional and basis set 6-31G (d). The calculated eugenol derivative i.e. 3,4-dimethoxy isobutyl cinnamate; 3,4-dimethoxy isoamyl cinnamate; 3,4-dimethoxy isohexyl cinnamate; 3,4 dimethoxy isoheptyl cinnamate; 3,4-dimethoxy isoctyl cinnamate. The calculated safrole i.e. 3,4-methylenedioxy isobutyl cinnamate; 3,4-methylenedioxy isoamyl cinnamate; 3,4-methylenedioxy isohexyl cinnamate; 3,4-methylenedioxy isoheptyl cinnamate; and 3,4-methylenedioxy isooctyl cinnamate. The main parameter in determining the potential of sunscreen compounds is energy gap. The results of computational calculations show that the 3,4-methylenedioxy isohexyl cinnamate has the smallest energy gap (HOMO-LUMO) of 0.15021 eV. This shows that 3,4-methylenedioxy isohexyl cinnamate has a better potential as an active sunscreen material. In addition, the elongation of the alkyl chain does not significantly affect the HOMO-LUMO energy difference

Synergistic UV protection effects of the lignin nanodiamond complex

There are various concerns with current sunscreen actives in the sun care industry which pushes for a natural-based active that is sustainable as well as effective. Lignin is a natural polymer, capable of ultraviolet (UV) filtration and maintaining photostability. In this study, a variety of tuneable lignin-poly(ethylene glycol) (LP) nanodiamond (LP–ND) complexes were developed with varying ratios of LP to NDs. There are two fractions of LP–NDs, which use detonation NDs (LP–rNDs) and furnace NDs (LP–mNDs). Both complexes demonstrated favorable UV filtration, enhanced photostability, and uniform dispersion in water and cream. The LP–mND had maintained its particle size at <200 nm with an increasing LP ratio from 0.5 to 20 times as opposed to the increased particle size of the LP–rND. The LP–mND complex excelled in its photostability during solar radiation from 1 h to 6 h, demonstrating its effectiveness in absorbing 70% in the UV B region. Results had indicated enhanced synergistic effect of LP–rNDs and LP–mNDs with commercial sunscreen. The LP–rND complex had enhanced the sunscreen from 29 to 62, whereas the LP–mND had further boosted the sun protection factor to 89. In a nutshell, the lignin nanodiamond complexes offer a sustainable alternative to current actives in the industry.

Challenging Cosmetic Innovation: The Skin Microbiota and Probiotics Protect the Skin from UV-Induced Damage.

Many studies performed in the last decade have focused on the cutaneous microbiota. It has been shown that this microbiota plays a key role in skin homeostasis. Considered as “a second barrier” to the environment, it is very important to know how it reacts to exogenous aggressions. The cosmetics industry has a started to use this microbiota as a source of natural ingredients, particularly ones that confer photoprotection against ultraviolet (UV) rays. Interestingly, it has been demonstrated that bacterial molecules can block UV rays or reverse their harmful effects. Oral probiotics containing living microorganisms have also shown promising results in restoring skin homeostasis and reversing the negative effects of UV rays. Microbial-based active sunscreen compounds have huge potential for use as next-generation photoprotection products.

Fall from GRASE: The Sunsetting of the Sunscreen Innovation Act

The 2020 Coronavirus Aid, Relief, and Economic Security (CARES) Act terminated the Sunscreen Innovation Act (SIA) that the Food &amp; Drug Administration (FDA) uses to determine sunscreen actives as safe and effective for human use. The Act also nullified a recent FDA proposal that reclassified 14 organic sunscreen actives as either not safe for human use or requires more data before being used in humans. Most sunscreen actives were approved in 1978; since that time the FDA has determined that over the last 20 years several changes have occurred leading to a substantial increase in sunscreen usage and exposure that increases the potential health risks associated with their use. Based on the scientific literature for the actives reviewed, it is clear that the SIA is needed to assure that sunscreen and other over-the-counter drugs are safe and efficacious for human use prior to entering the marketplace.

Adverse Reactions to Sunscreens.

Adverse reactions to sunscreens are uncommon in relation to their widespread use [Loden et al. Br J Dermatol. 2011;165(2):255-62; Jansen et al. J Am Acad Dermatol. 2013;69(6):867 e861-814; quiz 881-862] and can be related to both active and inactive ingredients in sunscreen products [DiNardo et al. J Cosmet Dermatol. 2018;17(1):15-19; Barrientos et al. Contact Dermatitis. 2019;81(2):151-52]. Pathogenetically, the main cutaneous adverse reaction patterns to sunscreens can be divided into allergic and irritant contact dermatitis, phototoxic and photoallergic contact dermatitis, contact urticaria, and, in solitary cases, anaphylactic reactions [Lautenschlager et al. Lancet. 2007;370(9586):528-37]. A summary is provided in Table <xref ref-type="table" rid="t01">1</xref>. Nearly all adverse effects due to active sunscreen ingredients reported to date are related to the organic UV filters, which are sometimes also referred to as "chemical UV filters." This imbalance is attributable to the lipophilic character and small molecular size of the organic UV filters that allow skin penetration, which is the basic requirement to initiate the sensitization [Stiefel et al. Int J Cosmet Sci. 2015;37(1):2-30]. In contrast, cutaneous adverse reactions to inorganic UV filters, initially termed "physical UV filters" owing to their firstly known "physical" mechanism of action through reflection and scattering [Stiefel et al. Int J Cosmet Sci. 2015;37(1):2-30], are only reported by case reports. Neither zinc oxide nor titanium dioxide possesses relevant skin-irritating properties or sensitization potential [Lau-tenschlager et al. Lancet. 2007;370(9586):528-37]. Adverse reactions to UV filters currently approved in the European Union as listed in the Annex VI (updated November 7, 2019) are summarized in Table <xref ref-type="table" rid="t02">2</xref>.

Lignin for pharmaceutical and biomedical applications – Could this become a reality?

Lignin is an aromatic biopolymer and a primary component of the cell walls in lignocellulosic biomass, where it constitutes between 15 and 40% of its dry mass. This percentage can vary, not only among plant species, but also among different cell types. Currently, the pulping and biorefinery industries worldwide extract large amounts of lignin, which is mostly combusted to generate the power needed to productively transform the lignocellulosic biomass. The specific composition and structure of this technical lignin depends on its botanical origin and on the extraction method applied. In general, however, lignin possesses antioxidant and antimicrobial properties, UV-absorbing capabilities, biocompatibility and low cytotoxicity. Moreover, lignin can increase the mechanical strength of numerous processed biomaterials. Accordingly, lignin is a promising aromatic raw material for the pharmaceutical and biomedical field. This work discusses the recent advances in the valorisation of lignin through the development of drug and gene delivery systems, wound dressings, tissue engineering or sunscreen actives. Finally, a brief overview on the current challenges and opportunities for making lignin-based products for pharmaceutical and medical applications a reality is also discussed.

Investigation of the chemical and optical properties of halogen-substituted N-methyl-4-piperidone curcumin analogs by density functional theory calculations.

Halogen-substituted N-methyl-4-piperidone curcumin analog compounds were studied for their molecular structure, molecular vibration analysis, natural bond orbital, ultraviolet spectra, molecular reactivity analysis, and nonlinear optical properties. The molecules in interest were the (3E,5E)-3,5-dibenzylidene-1-methylpiperidin-4-one along with its substituted halogen (X = F- or Cl- or Br-) at the ortho, meta and para position in the phenyl ring. The calculated geometrical parameters at B3LYP/6-311++G(d,p) were in good agreement with the available experimental XRD data. Using the frequency calculations, the molecular vibrational modes have been analyzed. Meanwhile, the hyperconjugative stabilization energies have been calculated using NBO analysis to address the donor and acceptor in the hyperconjugation. The calculated UV spectra at TD-CAM-B3LYP/6-311++G(d,p) show strong absorption around 300 to 320 nm which corresponds to the absorption in the UV-A and UV-B region. From molecular electrostatic potential surface, CO moiety is one of the electronegative regions in the compounds where the CX moiety is the other electronegative region of the compounds. Fluoro-substituted compounds are the compounds with the most electronegativity while bromo-substituted compounds are the compounds with the least electronegativity. Calculations of average local ionization energy surfaces have been performed to obtain information related to the local reactivity of the molecules where the phenyl becomes less reactive after the substitution. The calculated first hyperpolarizability is 6 to 17 times larger than urea, the standard nonlinear optic material. These findings imply that all of the molecules considered have potential to be applied as active sunscreen material or nonlinear optic material.

High-value utilization of kraft lignin: Color reduction and evaluation as sunscreen ingredient

Dark color of lignin puts brakes on its development as sunscreen ingredient. In order to address this issue, the color of lignin was whitened by facile and economical approach via solvent fractionation and follow-up acetylation. After the two-step treatment, the color of lignin was highly lightened by 313.5% owing to the separation of dark-colored condensed structures and the blocking of free hydroxyls. The UV absorbability of the light-colored lignin was investigated, which indicated that the UV absorbance of the light-colored lignin are not as strong as commercial sunscreen actives under certain wavelengths, however it presented broad-spectrum absorbability and obvious synergistic effects with the commercial sunscreen actives. Based on that, lignin-based sunscreen was prepared by blending light-colored lignin with an SPF15 lotion, and the SPF of the as-prepared lignin sunscreen was boosted from 15.3 to 75.2 under a lignin addition amount of 8%. The as-prepared lignin sunscreen is stable enough under UV irradiation and exhibits outstanding color performance, which make it possible to satisfy the daily requirement of consumers. Briefly, an effective approach was demonstrated in this work to prepare light-colored lignin, which makes lignin a green alternative to replace synthetic sunscreen actives and imparts lignin potentials in cosmetics applications.

Synthesis of cosmetic grade TiO2-SiO2 core-shell powder from mechanically milled TiO2 nanopowder for commercial mass production

TiO2 nanoparticles as an active sunscreen ingredient generate reactive oxygen species (ROS) upon UVA irradiation which is cytotoxic, genotoxic and potential to damage the DNA. The health concern and potential risks from TiO2 can be mitigated by shielding the particles through the suitable coating. Considering the advantages of SiO2, SiO2 coated TiO2 nanoparticles can be a potential material which can replace TiO2 for thickening, whitening, lubricating, and sunscreen ingredient in cosmetics. This article reports the synthesis of cosmetic grade TiO2-SiO2 core-shell nanopowder from mechanically milled TiO2 nanopowder for commercial mass production. From commercial TiO2 nanopowder was fabricated through size reduction by nanoset milling. Followed by the fabricated TiO2 nanopowder coated with SiO2 through sol-gel technique. A suitable optimum condition was explored for cosmetic grade TiO2-SiO2 core-shell nanopowder. Various physical properties and optical properties were analyzed. Synthesized of cosmetic grade TiO2-SiO2 core-shell nanopowder found to be at 100 nm size, with a homogeneous SiO2 coating having UVA protection factor 39 and sun protection factor (SPF) is 42. From the size, safety, and SPF perspective it can be an excellent cosmetic grade powder and from process simplicity perspective it can be commercially viable.

In vitro examination of an oleosome-based sun protection product on the influence of UVB-induced inflammation markers in human epidermal skin equivalent tissue model

In vitro human epidermal skin equivalent tissues (MatTek EpiDerm™) were employed to examine the influence of UVB radiation on various established inflammation markers in the presence of topically applied sunscreens. MatTek EpiDerm™ tissues were treated with 2.0mg/cm2 of an Experimental oleosome-based SPF 30 product or a commercial SPF 30 beach product. Tissues were irradiated with 300mJ/cm2 of UVB radiation. Inflammatory cytokines IL-1α, IL-6 and IL-8 as well as arachidonic acid cascade marker PGE2 were examined via ELISA-based antibody detection. Untreated tissues irradiated with 300mJ/cm2 of UVB radiation showed statistically significant upregulation of IL-1α, IL-6 and IL-8 as well as PGE2. Application of both the experimental oleosome-based SPF 30 formulation and the commercial SPF 30 formulation demonstrated an ability to prevent the upregulation of all four markers when applied prior to irradiation. The experimental oleosome-based SPF 30 product contained approximately 80% less sunscreen actives than the commercial formulation. This study demonstrates that in vitro reconstructed human tissues can be used to study the influences of sun screen actives in the presence of UVB radiation. The results support previously reported clinical results that demonstrated that oleosome-based sun care formulations can function with high protection effects with significantly less sun care actives.

Dermatological and environmental toxicological impact of the sunscreen ingredient oxybenzone/benzophenone‐3

Oxybenzone (Benzophenone-3) is an emerging human and environmental contaminant used in sunscreens and personal care products to help minimize the damaging effects of ultraviolet radiation. The Center for Disease Control fourth national report on human exposure to environmental chemicals demonstrated that approximately 97% of the people tested have oxybenzone present in their urine, and independent scientists have reported various concentrations in waterways and fish worldwide. Oxybenzone can also react with chlorine, producing hazardous by-products that can concentrate in swimming pools and wastewater treatment plants. Moreover, adverse reactions could very well be increased by the closed loop of ingesting fish contaminated with oxybenzone and/or washing the ingredient off our bodies and having it return in drinking water as treatment plants do not effectively remove the chemical as part of their processing protocols. In humans, oxybenzone has been reported to produce contact and photocontact allergy reactions, implemented as a possible endocrine disruptor and has been linked to Hirschsprung's disease. Environmentally, oxybenzone has been shown to produce a variety of toxic reactions in coral and fish ranging from reef bleaching to mortality. Lastly, with the rise in skin cancer rates and the availability of more effective sunscreen actives such as micronized zinc oxide and titanium dioxide, serious doubts about the relative prevention benefit of personal care products containing oxybenzone must be raised and compared with the potential negative health and environmental effects caused by the accumulation of this and other chemicals in the ecosystem.

Rejuvenation in neck appearance from topical treatment with physiologically-balanced growth factors, antioxidants and sunscreen actives

Rejuvenation in neck appearance from topical treatment with physiologically-balanced growth factors, antioxidants and sunscreen actives

Active sunscreen ingredients in Australia.

UV radiation exposure is the major contributor to photocarcinogenesis and photoageing. Reducing UV radiation exposure can be achieved by using adequate sunscreen preparations. The use of sunscreen can significantly reduce the incidence of squamous cell carcinoma, actinic keratoses and invasive melanoma. In the Australian market over 900 sunscreen products are available, each with their own brand, formulation and ingredients. It can be difficult for dermatologists and consumers to determine which are the most effective and appropriate products to use. We discuss the specific active ingredients found in sunscreen formulations available in Australia, their mode of protection, photostability, solubility, and side-effects and the methods used by the Therapeutic Goods Administration to determine the ratings and efficacy of each sunscreen.