Registration Dossier

Diss Factsheets

Environmental fate & pathways

Phototransformation in air

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Indirect photochemical degradation of mono-, and di-(sec-hexadecyl)naphthalene as mediated by OH- attack is estimated to have half-lives of 0.148 day or 1.78 hours based on a 12 -hour sunlight day, a rate of 72.07 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. 

Key value for chemical safety assessment

Half-life in air:
1.78 h

Additional information

Mono-, and di-(sec-hexadecyl)naphthalene has the potential to be degraded rapidly by-attack. However, multimedia distribution modeling predicts that the study substance will partition very little if any (0.05%) to the air compartment, partly due to its low vapor pressure (<0.00034 Pa) and its relatively short atmospheric oxidation half-life (1.78 hours). Therefore, photochemical degradation is unlikely to contribute to the loss of the study substance from the environment.