The oxygen we breathe has a diatomic structure. That is, a single molecule of oxygen is composed of a pair of oxygen atoms. Ozone, or trioxygen, is an unstable configuration of three oxygen atoms in one molecule. It forms in the Earth’s stratosphere when oxygen is exposed to ultraviolet light. At lower atmospheric levels, it is created by electrical discharges such as lightning or the reaction of sunlight with the atmospheric byproducts of fossil fuel combustion.
Ozone, like oxygen, is a gas. It exhibits a pale blue color in high concentrations and has a distinctive, pungent smell that can be detected by humans in concentrations as small as 10 parts per billion. When it decomposes, it forms the more stable oxygen molecule.
Ozone is a far more powerful oxidizing agent than oxygen. It is used in water treatment plants in place of chlorine to kill water-borne pathogens, since it leaves behind no taste or odor in the water. It is used to disinfect operating rooms, deodorize buildings after a fire, to kill bacteria and insects in food stores and for sanitizing food and textiles.
In the synthesis of lubricants, pharmaceuticals and other organic compounds, ozone is efficient at breaking down carbon-to-carbon chemical bonds during processing of raw materials. Its application on some fruits, such as tomatoes and pineapples actually increases their nutrient content.
The presence of ozone in Earth’s stratosphere is vital to protecting animal and plant life at the surface. It filters out a significant portion of the sun’s ultraviolet light that would otherwise damage living tissues. UV damage can cause genetic mutations in cells that would, without ozone’s filtering properties, lead to higher rates of cancer for instance.
Soon after the discovery of ozone in the mid-19th century, it was thought to be a healthy component of the lower atmosphere that we breathe. One California town even boasted of the naturally occurring high ozone concentration in its vicinity. By the early 20th century, however, it was clear that high concentrations of ozone damaged sensitive surfaces of our bodies such as the mucus membranes and lungs. Such damage may lead to shortness of breath, coughing and irritation of the eyes, nose and throat.
High levels of ozone in the outside air can lead to unhealthy levels as it seeps into buildings. Fortunately, due to ozone’s high level of reactivity with many compounds, it continually breaks down as it comes into contact with floors, walls and furniture.
However, much of it interacts with our bodies too. Recent research shows that some of the main reactants with ozone are the natural oils in human skin. Furthermore, the byproducts of this reaction, especially with cholesterol and squalene, may be more toxic to humans than ozone alone. These byproducts are present in house dust and the indoor atmosphere where they cling to walls and other surfaces.
The common reactant byproduct of ozone and skin oils is a class of carbonyl known as 4-OPA. Previously, there were no toxicological studies of these compounds. Early results, however, indicate that 4-OPAs sensitize human tissue to irritation and inflammation. Each molecule of 4-OPA produced by the interaction of one molecule of ozone appears to be more harmful than the original ozone itself.
Research into ozone’s dangers continues. If you live in an area of urban smog, it is advisable to keep doors and windows closed in order to reduce the level of ozone in your home especially when smog levels are high. Consider improving dust filtration in the home but avoid air-cleaning units that generate ozone themselves.
Appleby Systems can help you reduce the ozone in your home. Contact us today to find out how.