Global atmospheric changes such as depletion of ozone in the stratosphere are thought to lead to increased levels of ultraviolet radiation on earth. This can have adverse effects on human health, and long-term effects of ultraviolet light on the eye are of increasing concern. Ultraviolet light exposure to the eye has been associated with cataract formation and retinal degeneration. In both cases, it is hypothesized that ultraviolet light can initiate formation of free radicals, which can cause protein modification and lipid peroxidation. Several procedures can be recommended to prevent ultraviolet light damage to the eye, such as the use of suitable protective glasses when outdoors.