Registration Dossier

Administrative data

Link to relevant study record(s)

Description of key information

Soil photolysis is considered not a critical route of removal from the environment based on environmental distribution models.  The models indicate that less than 0.1% will partition to soil and sediments. In addition 1,1,1-trichloroethane is highly resistant to photolytic degradation but rapidly vaporises into the atmosphere.

Key value for chemical safety assessment

Additional information

In the 1996 UK review it is noted that the material is not expected to be present in soils or sediments. in addition trichloroethane is resistant to abiotic degradation (hydrolysis and photolysis) with half lives estimated in months rather than days. Contamination of soil and sediments is not predicted using environmental fate/distribution modelling. Levels of contamination of soil is predicted to be appreciably lower than that expected in surface and marine waters. It is generally accepted by reviewers that the levels of the material are so low in the soil/sediment compartment that for risk assessments this compartment can be ignored/discounted. Existing reviews particularly those conducted by Dutch authorities emphasise that soil contamination is a problem due to leaching into potable water aquifers. The reviewers identify the source and attributed the reason for the problem to leaching from uncontrolled contaminated waste sites/dumps and not to contamination arising from manufacture or transport of the material. Contamination of water is therefore considered unlikely when used as a transported intermediate as no release would occur.