Cause of stratospheric ozone layer depletion Ozone depletion in the stratosphere, linked to health effects like increased UV exposure, is mainly caused by the presence of which compounds?

Introduction / Context:
The stratospheric ozone layer filters harmful ultraviolet radiation. Its depletion increases skin cancer risk, eye damage, and ecosystem stress. Understanding the key chemical drivers of ozone loss is fundamental to environmental policy and engineering.

Given Data / Assumptions:

• We focus on stratospheric ozone depletion (not ground-level ozone or climate change).
• Candidate compounds include common air pollutants and specific halocarbons.

Concept / Approach:
Chlorofluorocarbons (CFCs) are extremely stable in the troposphere. They reach the stratosphere, where UV radiation releases chlorine radicals. These radicals catalytically destroy ozone via repeated reaction cycles, thinning the ozone layer. Policy actions such as the Montreal Protocol targeted CFC phase-outs for this reason.

Step-by-Step Solution:

Verification / Alternative check:
International assessments and satellite observations link CFCs with ozone holes, especially over polar regions; ozone recovery parallels reductions in controlled halocarbons.

Why Other Options Are Wrong:

Common Pitfalls:
Confusing climate change drivers with ozone-depleting substances; while both are atmospheric issues, the chemistries are distinct.

Final Answer:
CFC (chloro fluoro carbon)