Chemical Sunscreen Filters

What are chemical sunscreen filters and what do they do?

Chemical, or organic, UV filters are carbon-based molecules that absorb ultraviolet energy and convert it into a small amount of heat. Each filter covers a particular band, so sunscreens combine several to achieve broad-spectrum protection across UVB and UVA. Avobenzone covers long UVA but can degrade in sunlight unless stabilised; newer filters, such as bemotrizinol and bisoctrizole, are more photostable and cover both UVA and UVB. Chemical filters allow thin, invisible textures without a white cast, which many people find easier to apply generously and daily. Like mineral filters, they reduce sunburn, photoaging and pigmentation only when applied in sufficient amounts and reapplied. [1]

What does the evidence show?

Clinical evidence that regular sunscreen use reduces sunburn, photoaging and skin cancer risk is well established. Randomised clinical trials by the US Food and Drug Administration showed that several organic filters are absorbed into the bloodstream above a screening threshold under maximal-use conditions; the authors stated this does not mean the filters are unsafe and that people should continue using sunscreen while further safety data are gathered.

Who should avoid chemical sunscreen filters?

Some people develop allergic or irritant reactions to specific filters, particularly octocrylene or benzophenones, and those with sensitive or eczema-prone skin may prefer mineral filters. Anyone who reacts should note the filter list and choose different products. Concerns about absorption should be discussed with a doctor rather than abandoning sun protection.

Are chemical sunscreen filters available in Singapore?

Sunscreens are regulated as cosmetic products in Singapore, and only UV filters on the permitted list under the ASEAN cosmetic rules may be used, within set maximum concentrations. Several newer filters available in Asia and Europe are not approved in the United States, so formulations differ between markets. Look for broad-spectrum protection and an appropriate SPF.

If a dark patch, breakout or irritation is not responding to what you are using, the next step is a diagnosis rather than another product. See the Skin A–Z library for related ingredients.