Ozone Depletion & Skin Cancer: UV Radiation Is the Direct Cause

Ozone depletion increases UV‑B reaching Earth’s surface, which raises skin cancer risk—but the direct cause is excessive UV exposure, not the depletion itself.

Mechanism

• Stratospheric ozone absorbs UV‑B (280–315 nm).
• Thinning ozone → more UV‑B at ground level.
• UV‑B damages DNA (cyclobutane pyrimidine dimers) → mutations in p53, PTCH1 → basal/squamous cell carcinoma, melanoma.

Risk Factors (Modifiable)

• Intermittent intense sun exposure (sunburns, especially childhood).
• Chronic occupational exposure.
• Tanning beds (classified carcinogenic).
• Fair skin, many nevi, family history, immunosuppression.

Protection

• Broad‑spectrum SPF 30+ sunscreen, reapplied.
• UPF clothing, wide‑brim hat, sunglasses.
• Seek shade 10 am–4 pm.
• Avoid tanning beds.

Montreal Protocol Success

Global phase‑out of CFCs/halons → ozone layer recovering; expected pre‑1980 levels by ~2060. Continued UV vigilance still needed.