Description
Phenylbenzimidazole Sulfonic Acid (commonly abbreviated as PBSA) is a water-soluble organic UVB filter widely used in sunscreen formulations for effective protection against UVB radiation (280–320 nm). By efficiently absorbing high-energy UVB rays, PBSA helps prevent sunburn, DNA damage, and other harmful effects of sun exposure. Its primary role is to complement UVA filters to provide balanced, broad-spectrum sun protection.
PBSA stands out among UV filters because it is water-soluble, allowing formulators to create lighter, non-greasy sunscreen textures, such as gels, sprays, and water-based lotions. This property also makes it ideal for transparent sunscreen formulations that leave no white cast, making them suitable for all skin tones.
In sunscreen products, PBSA is often combined with UVA absorbers like Avobenzone and other UVB filters such as Octocrylene or Ethylhexyl Triazone to achieve higher SPF values and enhanced stability. It is compatible with a wide range of cosmetic ingredients and can be incorporated into both daily-use moisturizers and high-performance sunscreens for sports or beach activities.
PBSA is generally well tolerated by most skin types, with a low risk of irritation. However, because it is water-soluble, it is less water-resistant than oil-based UV filters, so water-resistant formulations require pairing it with additional film-forming agents or oil-soluble filters.
Regulatory approval permits PBSA use at concentrations up to 8% in the European Union, 10% in Japan, and varying levels in other regions. It is also FDA-approved in the United States for use in sunscreen formulations.
With its UVB protection efficiency, excellent cosmetic compatibility, and suitability for transparent, water-based sunscreens, PBSA remains a valuable ingredient in modern sun care products—particularly those designed for lightweight daily wear and comfortable, invisible sun protection.
