oxygenation

Oxygenation is the process of adding oxygen to a substance or, in biological contexts, supplying oxygen to a living system. In medicine and physiology, it most often refers to delivering or achieving adequate oxygen supply to the body's tissues.

In humans, oxygenation involves the collaboration of the lungs, blood, and circulatory system. Oxygen is inhaled into the lungs, diffuses into the blood, and binds to hemoglobin in red blood cells for transport to tissues. Common measures of oxygenation include arterial oxygen tension (PaO2) and oxygen saturation (SaO2). Normal PaO2 at sea level is about 80–100 mmHg, and SaO2 is typically 95–100%. Low arterial oxygen (hypoxemia) or inadequate tissue oxygen delivery (hypoxia) can result from respiratory, cardiac, or circulatory problems. Oxygen therapy and other interventions aim to improve oxygenation by increasing inspired oxygen or enhancing delivery to tissues.

In environmental science, oxygenation refers to the dissolved oxygen content of water, which supports aquatic life. Dissolved oxygen (DO) is influenced by temperature, salinity, mixing, and biological activity. Low DO can cause hypoxic conditions and dead zones; management includes aeration, water mixing, and reducing nutrient pollution that fuels oxygen-consuming processes.

In chemistry and biochemistry, oxygenation denotes the addition of oxygen to a molecule or functional group, such as hydroxylation or epoxidation. It can be part of metabolic oxidation-reduction processes, often catalyzed by enzymes in biological systems.