Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Phototransformation in air

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Available studies on the phototransformation of chloroform are not guideline-compliant. The available data indicate a rather slow dissipation of chloroform in air with an average half-life of approximately 70 days. The presence of smog may accelerate dissipation.

Key value for chemical safety assessment

Half-life in air:
70 d

Additional information

The studies of Pearson et al. (1975) and Singh et al. (1981) indicate rather long half-lives for photodegradation of chloroform in air of around 120 days. The half-life calculated by Singh et al. (1981) is for the reaction of chloroform with OH-radical being present in the atmosphere at a concentration of 1000,000 molecules per cm3. Klöpffer et al. (1988) studied the rate constant for reaction of chloroform with OH-radical in a standardised system by using a smog chamber equipped with 65 W Hg low pressure lamps. The reaction of atmospheric contaminants with OH-radical was described as the most important removal process from the atmosphere in their work. The concentration of OH-radical in the test atmosphere was considerably higher than the one assumed by Singh et al. (1981). Consequently, Klöpffer et al. (1988) found a higher rate constant for reaction of chloroform with OH-radical resulting in an estimated half-life for atmospheric chloroform of 26 days.