m-toluidine

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study meets generally accepted scientific principles.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 106 (Adsorption - Desorption Using a Batch Equilibrium Method)

GLP compliance:

no

Type of method:

batch equilibrium method

Media:

soil

Radiolabelling:

no

Test temperature:

20 +/- 2 °C

Analytical monitoring:

yes

Details on matrix:

- 4 different soils were used having an organic matter between 1.09 and 4.25 % and pH values ranging between 7.5 and 6.1
- air-dried and sieved (2 mm)

Details on test conditions:

- one gram of soil was shaken for 2 h with 10 mL chemical solution in 0.01 M CaCl2
- centrifugation for 10 min
- 5 ppm, 10 ppm, 15 ppm and 20 ppm of test substance served as initial concentrations

Type:

Koc

Value:

44.31

Temp.:

20 °C

Type:

log Koc

Value:

1.65

Temp.:

20 °C

Details on results (Batch equilibrium method):

In the reference, only the logKom value accounting for 1.41 is reported., which easily can be transfered to the resepective logKoc value by the following equation (according to Hong et al., 1996):
Koc= Kom*1.724

The adsorption isotherms for the substance was linear. When Kd was converted to Kom the value on each of the four soils was within 20% of the mean value of 1.41 (log Kom).

Validity criteria fulfilled:

not specified

Remarks:

Since the test is poorly reported the validity criteria cannot be assessed sufficiently. Nevertheless the test is considered as valid based on the data given.

Conclusions:

The experimentally determined logKoc of the substance is 1.65 at 20°C.

Executive summary:

The distribution of m-toluidine onto four different soils was investigated following a method similar to the OECD 106 (Briggs, 1981). Adsorption was measured in soils at four initial concentrations and the adsorption isotherms for the substance were linear. When Kd was converted to Kom the value on each of the four soils was within 20% of the mean value. The adsorption/desorption behaviour of m-toluidine is characterized by a logKoc of 1.65 at 20°C. In the reference, only the logKom value accounting for 1.41 is reported, which easily can be transfered to the resepective logKoc value by the following equation: Koc= Kom*1.724.

Description of key information

The experimentally determined logKoc of the substance is 1.65 at 20°C.

Key value for chemical safety assessment

Koc at 20 °C:

44.31

Additional information

The distribution of m-toluidine onto four different soils was investigated following a method similar to the OECD 106. Adsorption was measured in soils at four initial concentrations and the adsorption isotherms for the substance were linear. When Kd was converted to Kom the value on each of the four soils was within 20% of the mean value. The adsorption/desorption behaviour of m-toluidine is characterized by a logKoc of 1.65 at 20°C. In the reference, only the logKom value accounting for 1.41 is reported, which easily can be transfered to the resepective logKoc value by the following equation: Koc= Kom*1.724.

[LogKoc: 1.65]