Oxygenated water contains a significantly elevated concentration of dissolved oxygen (DO) compared to standard tap or bottled water. Regular water typically holds around 5 to 8 milligrams of dissolved oxygen per liter (mg/L). Commercial oxygenated products are manufactured to contain much higher levels, sometimes claiming concentrations of 40 mg/L or more. This article explores the scientific principles governing oxygen solubility and identifies practical, non-commercial methods for increasing the oxygen content of drinking water at home.
Understanding Dissolved Oxygen in Water
Dissolved oxygen refers to the non-compound oxygen molecules (\(\text{O}_2\)) physically mixed into the water, separate from the oxygen bonded to hydrogen in the \(\text{H}_2\text{O}\) molecule. The amount of oxygen water can hold is governed by physical laws, most notably Henry’s Law. This law states that the concentration of a gas dissolved in a liquid is directly proportional to the partial pressure of that gas above the liquid.
At standard atmospheric pressure, water can only absorb oxygen up to a certain saturation point. For example, at sea level and 20° Celsius, the maximum dissolved oxygen concentration is approximately \(9.03 \text{ mg/L}\). This saturation point limits simple home methods. The solubility of oxygen decreases significantly as the water temperature rises, meaning colder water can physically hold more gas molecules. Therefore, chilling water is a necessary step to maximize the oxygen content.
Practical Methods for Increasing Water Oxygen Content
The most accessible method for increasing dissolved oxygen involves physical aeration, which works by increasing the contact area between the water and the air. Vigorously shaking a bottle of water for several minutes creates small air bubbles that rapidly transfer oxygen into the liquid. A similar effect can be achieved by pouring water repeatedly between two containers from a moderate height, which agitates the water surface and exposes more water molecules to the surrounding air.
To maximize effectiveness, the water should be pre-chilled to a low temperature, ideally near \(4^\circ \text{C}\) (\(39^\circ \text{F}\)), to take advantage of the increased gas solubility in cold water. While simple agitation increases the oxygen level toward the saturation point, more sustained aeration can be achieved using basic equipment. A small, inexpensive aquarium air pump paired with an air stone can be used to bubble air through the water for a longer period.
The air stone breaks the air stream into tiny bubbles, maximizing the surface area for gas exchange and creating turbulence. This continuous agitation is more efficient than manual shaking and helps maintain a higher DO level, though it remains limited by the partial pressure of oxygen in the air. Achieving the highest, commercial-level concentrations requires specialized equipment that pressurizes the water with pure oxygen gas, a method not practical for home use.
Examining the Claims Associated with Oxygenated Water
Proponents of commercial oxygenated water often suggest that consuming the product can lead to various physical enhancements. Common assertions include that drinking this water can improve overall athletic performance and increase endurance during physical activity. It is also claimed that the extra oxygen aids in faster recovery after intense workouts and helps reduce muscle fatigue.
Other claims focus on internal body functions, suggesting that oxygenated water contributes to enhanced energy levels and improved digestive health. Furthermore, some brands propose that the elevated oxygen content can help speed up the body’s metabolism of alcohol. These claims motivate consumers seeking methods to increase the oxygen content of their water.