Chemistry of organic traces in air

✍ Scribed by Th. Class; K. Ballschmiter

• Book ID: 104623269
• Publisher: Springer Netherlands
• Year: 1988
• Tongue: English
• Weight: 610 KB
• Volume: 6
• Category: Article
• ISSN: 0167-7764
• DOI: 10.1007/bf00048330

✦ Synopsis

The occurrence of CH2Br2, CH 2BrC1, CH212, CH2Cll , CHBr3, CHBr2C1 , CHBrC12 and CH2Br-CH 2 Br in marine air and seawater from various sampling sites in the region of the Atlantic Ocean have been measured and evaluated. A correlation exists between high concentrations of these compounds in air and in water and the occurrence of algae at the coastlines of various islands (The Azores, Bermuda, Tenerife) and in a region of high bioaetivity in the Atlantic Ocean near the West African coast.

'Real-world' air-water concentration ratios derived from measurements in the open ocean identify the water mass near the African coast with its high primary production as a source for the above compounds. This region has to be discussed also as a possible secondary source in which CHBr2C1 , CHBrCI 2 and CH2CII can be formed via halogen-exchange. Whether CHBrC12 and CH2CII undergo transformation to CHC13 and CH2C12, respectively, is open to further investigations.

Direct photolysis and degradation by OH-radicals lead to a gradient in the marine troposphere with reduced concentrations for the organobromides above the tropospheric boundary layer.