What condition results from long exposures to high levels of partial pressure of oxygen at depth?

The condition that arises from long exposures to high levels of partial pressure of oxygen at depth is pulmonary oxygen toxicity. When divers are exposed to elevated levels of oxygen, particularly under increased pressure, it can lead to oxidative stress in the lungs. This can cause inflammation and damage to lung tissue, which may manifest as symptoms such as chest pain, cough, and difficulty breathing. The prolonged exposure to high partial pressures of oxygen is particularly concerning for pulmonary toxicity as it can lead to serious health complications if not managed properly.

In contrast, CNS oxygen toxicity primarily affects the central nervous system and is characterized by symptoms such as seizures and visual disturbances, occurring at shorter exposures and higher pressures. Barotrauma relates to injuries from pressure changes and not specifically to oxygen levels, while hypercapnia involves elevated carbon dioxide levels, which is not directly caused by prolonged high oxygen exposure. Thus, pulmonary oxygen toxicity is specifically linked to extended exposure to high partial pressures of oxygen, making it the correct answer.