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Environmental fate & pathways

Phototransformation in air

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Description of key information

The major components (C20-C22) in the reaction products of 1-decene, 1-dodecene, and 1-octene, hydrogenated have the potential to be degraded rapidly by OH- attack.  However, multimedia distribution modeling predicts that the main components in the reaction products of 1-decene, 1-dodecene, and 1-octene, hydrogenated will partition very little if any (~0.3-0.4%) to the air compartment, partly due to its low  vapor pressure and its relatively short atmospheric oxidation half-life (4.5-5.0 hours).  Therefore, photochemical degradation is unlikely to contribute to the loss of the reaction products of 1-decene, 1-dodecene, and 1-octene, hydrogenated, from the environment.

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Additional information

The photochemical degradation of the main constituents (i.e., C20-C22 hydrogenated components) of the reaction mass of 1-decene, 1-dodecene, and 1-octene, hydrogenated was calculated using the EPA EpiSuite (AOPWIN) in order to estimate their atmospheric oxidation half-lives under 12-hr exposure to sunlight and hydroxyl radicals.

Indirect photochemical degradation of the major C20-C22 components in the multi-constituent reaction mass of 1-decene, 1-dodecene, 1-octene, hydrogenated as mediated by OH- attack is estimated to have half-lives of 0.38-0.42 days or 4.5-5.0 hours based on a 12 -hour sunlight day, a rate of 25.5 to 28.3 E-12 cm3/molecule-sec, and an average OH- concentration of 1.5E6 OH-/cm3. A 12-hour day half-life value normalizes degradation to a standard day light period during which hydroxyl radicals needed for photolysis are generated in the atmosphere.