Registration Dossier

Diss Factsheets

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Hydrolysis:

The hydrolysis of chlorocresol was estimated to be 0.0000000000256787 cm3/molecule - seconds. The estimated half life of the substance indicates that the substance is non persistent in nature as the OH rate constant is negligible and so the substance is biodegradable.

Biodegradation in water: screening tests:  

According to the PBT profiler model, Chlorocresol degrades 50% in water in 38 days, suggesting that it is readily biodegradable in water and it will not be persistent in the aquatic environment

Media

Half-Life 
(days)

Percent in
Each Medium

 water

 

38

19%

 

Biodegradation in water and sediment: simulation tests:

Chlorocresol degrades 50% in water in 37.5 days, suggesting that it is readily biodegradable in water. However, in the sediment Chlorocresol has a long half life of 337.5 days. Thus it can be concluded that Chlorocresol will be persistent in the sediment given its long half life of 337.5 days.

Media

Half-Life 
(days)

Percent in
Each Medium

Water

37.5

19.1%

Sediment

337.5

0.519%

 

Biodegradation in soil:

Half-life of chlorocresol in soil was estimated to be 1800 hours i.e. 75 days .Thus is can be concluded that chlorocresol is persistent in soil given the half life of 75 days which is slightly greater than the threshold of 60 days (half life) indicating ready bio-degradability and low persistence in soil

Media

Half-Life 
(days)

Percent in
Each Medium

 Soil

 

75

80%

 

Bioaccumulation: aquatic / sediment:

BCF values of 5.5 to 11 and 6.7 to 13 were measured using initialChlorocresolconcentrations of 2 ug/l and 20 ug/l, respectively. Tests were conducted in a continuous flow system with six weeks exposure using carp having an average lipid content of 4.9 percent. According to a classification scheme, these BCF ranges suggest the potential for Bioconcentration in aquatic organisms is low (SRC). For the purpose of chemical safety assessment and dossier preparation, Bioconcentration factor of 11 has been considered.

Adsorption / desorption:

The Koc of chlorocresol was found to be 490. According to a classification scheme, this Koc value suggests that chlorocresol is expected to have moderate mobility in soil. In addition, this chemical was found to be mobile in an activated carbon-sand filter system; this was considered to be indicative of a low adsorption potential in soil systems.