What is oxygen toxicity, and how does it impact divers?

Oxygen toxicity occurs when divers are exposed to high partial pressures of oxygen, leading to harmful effects, particularly on the central nervous system. This condition can arise at depths greater than approximately 20 meters (66 feet) when using pure oxygen or oxygen-rich gas mixtures. At high pressures, the amount of dissolved oxygen in the body increases, which can lead to symptoms such as nausea, twitching, visual disturbances, and in severe cases, convulsions, and loss of consciousness.

Understanding the condition is crucial for divers because it necessitates careful monitoring of oxygen exposure and adherence to safe diving practices. The other options do not accurately describe oxygen toxicity. For instance, low oxygen levels causing hypoxia relates to insufficient oxygen, rather than excess, while adaptation to high oxygen levels is not a characteristic of oxygen toxicity, nor is it a term for nitrogen's effects under pressure.