Physical Sunscreen Vs Chemical Sunscreen

• Protection Range: Primarily blocks UVB and some short-wave UVA (320–340 nm), but is less effective against long-wave UVA (340–400 nm).
• Characteristics: Has a whiter texture and may leave a white cast; suitable for sensitive skin or short periods of sun exposure.
  

Chemical sunscreens (also known as organic sunscreens) protect the skin by absorbing UV rays and converting them into heat. Unlike physical sunscreens that reflect UV rays, chemical sunscreens penetrate the outer layer of the skin and neutralize harmful radiation through a photochemical reaction. However, they may cause irritation in sensitive skin and need to be applied in advance to be effective.

Main Chemical Sunscreen Ingredients:

Oxybenzone:

This chemical UV filter can penetrate the skin and may disrupt the endocrine system, potentially affecting hormone levels. Studies have linked it to allergic reactions and possible reproductive issues. It has also been detected in human blood, urine, and breast milk, raising concerns about systemic absorption.

• Current status: Due to environmental concerns (such as coral reef damage), places like Hawaii have banned its use. Its safety is currently under review by regulatory bodies such as the U.S. Food and Drug Administration (FDA).
  

Octinoxate (Octyl Methoxycinnamate):

Another chemical UV filter that may have endocrine-disrupting effects. It has been detected in human tissues and the environment. It may cause skin allergies in sensitive individuals.

• Status: Due to environmental concerns, it is restricted in certain regions (such as Hawaii and Palau). Its safety for human use is still under ongoing evaluation.

Homosalate

This UV filter may disrupt hormones, particularly estrogen. After sunscreen application, homosalate levels detected in human blood have exceeded the FDA’s safety threshold. Its breakdown products may also be toxic.

• Status: Currently under further safety review by the FDA.

Octocrylene:

May cause skin allergies and potentially disrupt the endocrine system. Over time, it can degrade in products into benzophenone, a suspected carcinogen.

• Status: Growing concerns have led some to call for restrictions on its use due to potential environmental and health risks.

Avobenzone:

Although generally considered safer, avobenzone breaks down under sunlight and may form harmful byproducts. It can also cause skin irritation in some users.

• Status: Widely used, but requires stabilisers to maintain effectiveness. Its long-term safety is still under investigation.
  

Based on the above comprehensive comparison, physical sunscreen stands out for its gentle nature, making it the top choice for sensitive skin, pregnant women, and infants.

This type of sunscreen uses natural mineral ingredients like zinc oxide to form a gentle protective barrier on the skin's surface. It doesn’t penetrate the skin but effectively reflects UV rays, offering you peace-of-mind protection.

One of the key advantages of physical sunscreen is its immediate effectiveness, it starts working the moment you apply it. Especially ideal for those who prioritise ingredient safety, it contains no chemical absorbers, significantly reducing the risk of allergic reactions. While the texture can feel slightly rich, modern formulations have improved greatly. Many brands, such as Ms. Chu Soap & Beaut, now offer lightweight mineral sunscreens that maintain the gentle benefits of physical protection without the heaviness.