Can sunscreens, the things meant to protect our skin from sun and its UV rays cause cancer? Sunscreen emerged as a breakthrough in the 1930s and ’40s, celebrated for reducing sunburn and lowering skin cancer rates. However, decades later, evidence suggests that some formulations—especially chemical sunscreens—may carry unintended health risks, including cancer‑promoting effects, hormone disruption, allergic reactions, and environmental harm.

Skin Cancer: More Sunscreen, Not Less?

It seems counterintuitive: as sunscreen use has soared, some studies find flat or even rising skin cancer incidence among regular users. A 2017 meta‑analysis of 29 studies involving 313,717 individuals found no statistically significant link between sunscreen use and reduced melanoma or non‑melanoma skin cancer rates. The melanoma odds ratio and non‑melanoma indicated no apparent protective or harmful effect.

However, context matters. Earlier datasets from the 1970s–80s showed up to a 2.35× higher melanoma risk in sunscreen users—likely due to increased sun exposure once protected. Meanwhile, modern studies show consistent sunscreen use does reduce melanoma risk by around 50%, especially when combined with other sun‑safe behaviours.

The measure takeaway from this is that sunscreen alone isn’t enough. Users must use it correctly—broad-spectrum SPF 30+, reapplied, and paired with shade and clothing—otherwise, they may be lulled into more prolonged sun exposure that counters the benefits.

The Hidden Hazards: Chemical Filters & Carcinogens

It’s not UV rays alone that worry experts today, but some ingredients in sunscreen formulas—with chemicals like oxybenzone, octocrylene, homosalate, and others under scrutiny.

1. Oxybenzone (Benzophenone‑3)

• Detected in 96% of U.S. adults’ urine and breast milk and 100% of children tested—indicating chronic absorption.
• Studies show that 4–9% of applied doses absorb systemically, lingering for days.
• Linked to photoallergic dermatitis, forming free radicals under UV light that could damage cells.
• Lab and animal studies show endocrine disruption: weak estrogenic and anti‑androgenic effects, thyroid interference, and adrenal impacts.
• The EU labels benzophenones as “possible human carcinogen(s)” and hormone disruptors; oxybenzone is banned in sunscreens in Hawaii, Palau, and Thailand.

2. Octocrylene

• This UVB/UVA‑spectrum filter can break down into benzophenone—a compound with genotoxic, DNA‑damaging potential.
• It absorbs 14× levels above the FDA’s systemic exposure safety threshold and is tied to endocrine disruption and allergies.

3. Homosalate & Octinoxate (Octyl Methoxycinnamate)

• Both act as endocrine disruptors, mimic estrogens, and are absorbed through the skin and into breast milk.
• Octinoxate is banned in Hawaii and Palau due to both environmental harm and its systemic absorption.
• Cinnamates like octinoxate and octocrylene are known to interfere with estrogen, progesterone, and thyroid hormones.

4. Avobenzone

• Although UVA‑effective, it degrades rapidly in sunlight—up to 50% loss within 30 minutes—creating free radicals that damage skin cells.
• Often used with stabilisers (like octocrylene), increasing exposure to multiple chemicals.

5. Retinyl Palmitate (Vitamin A ester)

• Once used in ~41% of sunscreens, it is now down to ~2% due to its instability in sunlight, which can accelerate tumour and lesion development.

6. Benzene Contamination in Aerosols

• In 2021, ~27% of aerosol sunscreens tested contained benzene, a known carcinogen; some batches had levels up to 6 ppm—a major red flag.

Hormonal Havoc, Allergies, & More due to sunscreen filters

Beyond cancer, sunscreen chemicals carry other health concerns:

• Hormone disruption: Animal studies show altered sexual development, sperm impairment, thyroid disruption, and puberty delays from benzophenones or cinnamates.
• One human study found intermittent testosterone dips in men after one week using combined filters (oxybenzone, MBC, octinoxate)
• Allergic/photoallergic dermatitis: Oxybenzone, octocrylene, avobenzone, cinnamates, and benzophenones are top culprits.
• Researchers have correlated Frontal fibrosing alopecia (scalp hair loss) with sunscreen use—users had 2.2× the odds—though causality remains uncertain.
• Neurotoxic concerns: Some filters cross the blood‑brain barrier in animals, potentially affecting development and neuroendocrine systems.

Regulation & Market Realities in India

Unfortunately, with the Indian regulation, lawmakers have yet to catch up with the booming cosmetic and skin care industry, making the brands that use these ingredients in higher dosages not answerable to anyone. This exposes the general public to greater risk.

• India classifies sunscreens as cosmetics, meaning no pre-launch safety testing is mandatory—unlike India’s drug-level oversight in the U.S.
• Consumers face labelling inconsistencies—many products carry “mineral sunscreen” claims while featuring chemical filters.
• Anecdotally, brand transparency varies, especially with smaller Indian brands.

Download our guide for ingredients to look out for when purchasing a sunscreen!

What Indian Consumers Should Do

1.  Choose mineral-based sunscreens with zinc oxide and titanium dioxide—they aren’t absorbed, offer adequate broad-spectrum     protection, and are dermatologist-endorsed.
2.  Avoid inhaling large amounts of spray and aerosol sunscreens—2012’s benzene contamination recalls should serve as a warning.
3.  Carefully read the labels—don’t let “mineral” claims sway you; check for banned or questionable filters like oxybenzone, octinoxate,   homosalate, and avobenzone.
4.  Reapply and layer protection: SPF 30+ every two hours, shade, UPF clothing, hats, and sunglasses.
5.  Watch for skin reactions—if you experience rashes, dermatitis, or sensitivity, temporarily stop using the sunscreen, then patch-test   mineral alternatives.
6.  Advocate for better regulations: push Indian regulators to require pre-market safety with independent testing, reduce contamination   risks, and enforce truthful labelling.

The Bigger Picture

Sunscreens likely still play a protective role when used correctly. But rising concerns about specific chemical filters—especially in frequent or high-exposure contexts—demand caution. Chemical formulations may lead to unintended consequences: systemic absorption, hormone disruption, allergic reactions, ecological damage, and possibly genotoxic carcinogens leading to rise in skin cancers.

As research—and regulation—evolve, the safest approach right now is transparent: favour mineral filters, avoid questionable chemicals, and don’t rely on sunscreen alone. Sun protection should be a comprehensive approach, with product choice as one part of a larger, more innovative strategy.