Periodontal treatment is the specialist cleaning of your teeth and gums to help control the bacteria that cause gum disease. Gum disease is caused by the germs (bacteria) which live in your mouth.
Ground-Level Ozone (O 3). Ground-level ozone is a colorless and highly irritating gas that forms just above the earth's surface.It is called a secondary pollutant because it is produced when two primary pollutants react in sunlight and stagnant air.round-Level Ozone (O 3). Ground-level ozone is a colorless and highly irritating gas that forms just above the earth's surface.
Photograph by Stephen G. St. John. The ozone layer is a belt of naturally occurring ozone gas that sits 9.3 to 18.6 miles (15 to 30 kilometers) above Earth and serves as a shield from the harmful ultraviolet B radiation emitted by the sun.Ozone is a highly reactive molecule that contains three oxygen atoms.It is constantly being formed and broken down in the high atmosphere, 6.2 to 31 miles (10 to 50 kilometers) above Earth, in the region called the stratosphere.oday, there is widespread concern that the ozone layer is deteriorating due to the release of pollution containing the chemicals chlorine and bromine. Such deterioration allows large amounts of ultraviolet B rays to reach Earth, which can cause skin cancer and cataracts in humans and harm animals as well.