Ozone, the first allotrope of a chemical element to be described by science, . The odour from a lightning strike is from ions produced during the rapid chemical changes, not the ozone itself. It is present in low concentrations throughout the Earth's atmosphere. It has many industrial and consumer applications as well as being used in ozone therapy. Ozone will oxidize metals except gold, platinum, and iridium to oxides of the metals in their highest oxidation state. Ozone can be used to remove manganese from the water, forming a precipitate which can be filtered. The highest levels of ozone in the atmosphere are in the stratosphere, in a region also known as the ozone layer between about 10 km and 50 km above the surface. Here it filters out the shorter wavelengths less than 320 nm of ultraviolet light 270 to 400 nm from the Sun that would be harmful to most forms of life in large doses. These same wavelengths are also among those responsible for the production of vitamin D, which is essential for human health. Ozone can be used for bleaching substances and for killing bacteria. Disinfect laundry in hospitals, food factories, care homes etc, Disinfect water before it is bottled, deodorize air and objects, such as after a fire, kill bacteria on food or on contact surfaces, scrub yeast and mold spores from the air in food processing plants, wash fresh fruits and vegetables to kill yeast, mold and bacteria, chemically attack contaminants in water such us iron, arsenic, hydrogen sulfide, nitrites, and complex organics lumped together as color, provide an aid to flocculation (agglomeration of molecules, which aids in filtration, where the iron and arsenic are removed).