Chemical sunscreens are some of the most popular sun protection options on the market. They offer lightweight formulas and invisible finishes that suit a variety of skin tones. However, popular as they are, some lingering questions remain about their safety and environmental impact. In this article we unpack everything you need to know about chemical sunscreens, including how they work, their benefits and their safety. We also review the evidence on whether chemical sunscreens cause cancer, whether they are safe in pregnancy and how they affect marine ecosystems.
What are Chemical Sunscreens?
Unlike physical (mineral) sunscreens that sit on the skin’s surface and reflect UV rays, chemical sunscreens work by interacting with UV light to neutralise its harmful effects. Chemical (or organic) sunscreens contain active ingredients that absorb UV radiation before it can damage the skin and convert it into heat, which the skin then releases. Their lightweight, invisible nature makes them popular for daily wear, especially under makeup or in humid climates. They also tend to look more natural on people with skin of colour.
What are the Types of UV Filters in Chemical Sunscreens?
UV filters are the active ingredients that make chemical sunscreens work. Different filters absorb specific wavelengths of light, so chemical sunscreens usually contain one or more filters to provide broad-spectrum protection. This lets them work against both UVA rays (which cause premature ageing) and UVB rays (which cause sunburn). The most common UV filters in chemical sunscreens include the following.
- Oxybenzone: This filter absorbs both UVB and shortwave UVA rays. Oxybenzone offers partial broad-spectrum protection, which is why it often appears alongside other filters to boost efficacy. There is some controversy around using oxybenzone, though, due to potential hormonal effects and environmental concerns.
- Avobenzone: The main value of avobenzone is excellent protection against UVA rays, which penetrate deeper into the skin and contribute to ageing and skin cancer. Formulators often pair it with stabilising agents, since it can degrade quickly in sunlight. Avobenzone is considered safe for most skin types, but some people may notice mild irritation, particularly on sensitive skin.
- Octinoxate: This UVB filter protects the skin from sunburn and UV-induced damage. It is lightweight and easy to formulate with, which makes it a popular choice. However, like oxybenzone, it has raised environmental concerns over its impact on coral reefs. It also does not usually suit sensitive skin, since it can cause irritation or allergic reactions in some people.
- Octisalate: Another UVB filter, octisalate mainly stabilises other sunscreen ingredients like avobenzone. It extends the sunscreen’s effectiveness by slowing the breakdown of active ingredients. Octisalate is gentle and rarely irritating, so it suits sensitive or reactive skin.
- Octocrylene: This photostable filter absorbs UVB and some UVA rays, so it also helps prevent the breakdown of less stable ingredients like avobenzone. Unfortunately, octocrylene has been linked to allergic reactions, especially in sensitive skin. It is also under scrutiny for its potential environmental impact on marine ecosystems.
- Homosalate: Mainly a UVB filter, homosalate helps prevent sunburn and protects the skin from UVB-induced damage. It works alongside other filters to provide broad-spectrum protection. Although considered safe in regulated amounts, there is ongoing research into its potential to disrupt hormones at higher concentrations.
What are the Benefits of Chemical Sunscreens?
A number of things make chemical sunscreens a popular choice in skincare, mostly their effectiveness, versatility and ease of use. The main benefits include the following.
- Lightweight and invisible finish: One of the biggest draws is their lightweight texture. Unlike mineral sunscreens, which can leave a white cast, chemical sunscreens absorb fully to leave an invisible finish. This suits people with darker skin tones, or anyone who prefers a smooth, transparent base under makeup.
- Effective broad-spectrum protection: Because there are many UV filters and chemical sunscreens often combine several per product, they provide comprehensive protection against both UVA and UVB rays.
- Ideal for everyday wear and easy reapplication: Their lightweight formulation and invisible finish make chemical sunscreens perfect for daily use. They layer easily over other skincare and under makeup, and they come as sticks, powders and sprays, which makes reapplication throughout the day straightforward.
- Water resistance: Many chemical sunscreens are water-resistant, which makes them a good choice for active lifestyles. They are less likely to rub off during outdoor activities, swimming or exercise, so your skin stays protected even with sweat or water. You still need to reapply throughout the day, though.
- Versatility: Chemical sunscreens are highly versatile and suit different skin types. They come in a range of bases including gels, lotions, sprays, powders and sticks. Each one can target specific needs, with hydration for dry skin, oil control for acne-prone or oily skin, and antioxidants like vitamin C or E for skin ageing. Many also come tinted, as a lighter alternative to makeup.
What is the Safety of Chemical Sunscreens?
Regulatory authorities like the FDA and European Commission approve several chemical UV filters for use. They are generally safe, but like any skincare product they can have side effects. These include the following.
- Skin irritation
- Eye burning
- Allergic reactions
- Possible hormonal disruption with high doses of oxybenzone and homosalate, though more evidence is needed
Despite their benefits, popularity and approval status, some concerns linger around the long-term effects of chemical sunscreens. The main worries tend to focus on the following.
- Whether chemical sunscreens cause cancer: There is no direct evidence that chemical sunscreens cause cancer in humans. However, certain filters such as oxybenzone have raised concerns over potential hormonal disruption at high doses. Regulators in the EU and USA cap the concentration of these filters at a level they consider safe.
- Chemical sunscreens and sensitive skin: UV filters such as avobenzone and oxybenzone can cause stinging, redness or irritation, particularly around the eyes.
- Chemical sunscreens during pregnancy: If you are pregnant, the current advice is to avoid certain chemical UV filters, particularly oxybenzone, due to possible effects on hormones. Instead, opt for oxybenzone-free chemical sunscreens or switch to pregnancy-safe mineral sunscreens containing zinc oxide or titanium dioxide.
Are Chemical Sunscreens Reef-Safe?
There is some scrutiny around chemical sunscreens and their environmental impact, particularly on coral reefs and marine life. Ingredients like oxybenzone and octinoxate may contribute to coral bleaching and harm marine ecosystems. To address this, many brands now offer reef-safe or ocean-friendly chemical sunscreens that exclude these ingredients. Look for products that meet the following.
- Carry a reef-safe label
- Do not contain oxybenzone, octinoxate or octocrylene
- Use alternative UV filters like Tinosorb or Mexoryl, which are safer for the environment
How Do You Choose the Right Chemical Sunscreen?
Finding the right chemical sunscreen can feel overwhelming given how many products exist. Focus on a few key factors like formula type, active ingredients and your specific needs. When choosing, consider the following.
- Look for broad-spectrum protection: Broad-spectrum sunscreens protect against both UVA and UVB rays, which helps prevent premature ageing, sunburn and long-term skin damage.
- Check the ingredients: Avoid products containing oxybenzone and octinoxate if you are concerned about potential hormonal effects or environmental harm. Look instead for safer alternatives like Tinosorb S/M or Mexoryl SX.
- Choose the right formula for your skin type: For dry skin, opt for hydrating creams or lotion-based sunscreens with added emollients. For oily or acne-prone skin, lightweight gels or fluids help avoid clogged pores. Combination skin may benefit from hybrid formulas that blend chemical and mineral filters. For sensitive skin, choose fragrance-free sunscreens with gentler filters like octisalate.
- Pregnancy-safe options: If you are pregnant or breastfeeding, prioritise oxybenzone-free products or mineral sunscreens to avoid potential hormonal effects.
- Eye-friendly sunscreens: If chemical sunscreens tend to sting or burn your eyes, opt for formulas labelled safe for eyes, or use stick sunscreens for precise application that avoids migration into the eye area.
- Consider your lifestyle: For active or outdoor lifestyles, choose a water-resistant sunscreen that stays effective during swimming or sweating. For daily use, lightweight formulas that layer well under makeup, or tinted options that double as cosmetics, work well.
How Do You Find the Right Product?
Chemical sunscreens come in various formulations to suit different preferences and needs. Lotions and creams are ideal for dry or normal skin, since they hydrate while applying evenly. For oily or acne-prone skin, gels and fluids give a lightweight, quick-absorbing option that avoids clogging pores. Sprays are convenient for the body and for reapplication through the day, although they are less precise and not recommended for direct use on the face due to inhalation risks. Finally, stick sunscreens are compact, mess-free and perfect for targeted application on areas like the face or neck, which makes them a great choice for on-the-go touch-ups.
Chemical sunscreens are lightweight, effective and great for daily wear. They offer invisible protection, which makes them attractive across a wide range of skin tones. Despite the controversies, they remain safe and carry approval for use in skincare. Some UV filters may carry risks related to hormonal changes, irritation and marine safety, but you can sidestep these by choosing reef-safe and oxybenzone-free options that protect your skin and the environment. Whatever you choose, remember that the best sunscreen is the one you will actually use every day, so pick whatever looks and feels good on your skin.
At City Skin Clinic, we are passionate about personalised skincare. We offer custom skin and hair loss treatments using prescription-strength ingredients including tretinoin and hydroquinone where appropriate. Our doctors treat conditions including acne, hyperpigmentation, melasma and skin ageing via bespoke compounded treatments designed around you. Book a video consultation or start your online consultation today. Your journey towards great skin starts here.
This article is intended for general informational purposes only and is not a substitute for medical advice, diagnosis or treatment. Always consult a qualified medical professional with any concerns about your skin or treatment options.
