Dichloromethylbenzene

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

.
The substance described in this dossier is an isomeric mixture of five position isomers of dichlorotoluene. The similarities concerning chemical structure and key intrinsic properties such as log Kow and water solubility lead to the assumption that the values for ecotoxicological endpoints will also be very similar for the individual isomers and the mixture of isomers and that therefore results obtained with isomers can be useful for the assessment of the mixture. Study report peer-reviewed by OECD and cited in OECD SIDS Dossier, performed according to OECD-Guideline and GLP, only short abstract available

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Deviations:

not specified

GLP compliance:

yes

Specific details on test material used for the study:

Details are not provided

Radiolabelling:

not specified

Analytical monitoring:

yes

Details on sampling:

Detials are not provided

Buffers:

Detials are not provided

Estimation method (if used):

Detials are not provided

Details on test conditions:

Detials are not provided

Number of replicates:

Detials are not provided

Positive controls:

not specified

Negative controls:

not specified

Statistical methods:

Detials are not provided

Preliminary study:

Detials are not provided

Test performance:

No remarks

Transformation products:

not specified

Details on hydrolysis and appearance of transformation product(s):

Detials are not provided

pH:

4

DT50:

> 1 yr

Type:

not specified

pH:

7

DT50:

> 1 yr

Type:

not specified

pH:

9

DT50:

> 1 yr

Type:

not specified

Other kinetic parameters:

Detials are not provided

Details on results:

The result was cited as following: "not hydrolysed"

No remarks

Validity criteria fulfilled:

not specified

Conclusions:

2,4 - dichlorotoluene is hydrolytically stable.

Executive summary:

The hydrolytic behaviour of 2,4 - dichlorotoluene was tested according to OECD 111. 2,4 - dichlorotoluene was reported to be hydrolytically stable. The hydrolytic half-life at pH 4.0, 7.0, and 9.0 was deduced for this dossier to be greater than 1 year.

Reference: MITI, 1993

Description of key information

As reported in SIDS, the main isomer 2,4-dichlorotoluene was found to be hydrolytically stable at pH 4, 7, and 9 in an OECD 111 test performed by MITI, Japan. In this dossier, the DT50 of this isomer is therefore indicated to be >1 year. This DT50 is also applicable to the DCT mixture. 

Key value for chemical safety assessment

Half-life for hydrolysis:

1 yr

Additional information

The hydrolytic rate constant was not reported. The result was cited as "not hydrolysed at pH 4, 7 and 9". For the dossier preparation a DT50 > 1 year was deduced. This results in a hydrolytic rate constant of 7.89E-5 hours-1, calculated from ln2/DT50.

The study is peer-reviewed and cited in the SIDS for 2,4 - dichlorotoluene. Since the study was performed according to OECD Guideline 111 and GLP by MITI Japan, the reliability of the result is considered to be 2. Therefore, the study fulfills the requirements for a key study.

Reference: MITI, 1993

Further studies are not available for dichloromethylbenzene. 2,4 -dichlorotoluene is one of two main isomers of the DCT-mixture described in this dossier. It is assumed, that the other isomers have the same hydrolytic behaviour and therefore this worst case result may be used for the dichloromethylbenzene mixture as well.