Registration Dossier

Environmental fate & pathways

Adsorption / desorption

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
adsorption / desorption
Remarks:
adsorption/desorption
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
comparable to guideline study
Principles of method if other than guideline:
For sorption and desorption, each NAC (nitroaromatic compound) was extracted from the soil using acetonitrile, as described in EPA SW-846 Method 8330. NAC concentrations were determined by reversed-phase HPLC-PDA. LC/MS was used to to identify and verify TNT metabolites.
GLP compliance:
not specified
Type of method:
other: natural and model sterile and nonsterile soils using the methods of Huang et al. (20)
Media:
soil
Radiolabelling:
no
Test temperature:
25C
Sample No.:
#1
Duration:
22 h
Initial conc. measured:
ca. 5 other: mg/L
pH:
5.5
Temp.:
25 °C
Sample No.:
#2
Duration:
22 h
Initial conc. measured:
ca. 10 other: mg/L
pH:
5.5
Temp.:
25 °C
Sample No.:
#3
Duration:
22 h
Initial conc. measured:
ca. 15 other: mg/L
pH:
5.5
Temp.:
25 °C
Sample No.:
#4
Duration:
22 h
Initial conc. measured:
ca. 30 other: mg/L
pH:
5.5
Temp.:
25 °C
Sample No.:
#5
Duration:
22 h
Initial conc. measured:
ca. 50 other: mg/L
pH:
5.5
Temp.:
25 °C
Sample no.:
#1
Duration:
44 h
pH:
5.5
Temp.:
25 °C
Key result
Type:
Kd
Value:
ca. 6.38
Temp.:
25 °C
Remarks on result:
other: sorption by topsoil
Type:
Kd
Value:
ca. 223.63
Temp.:
25 °C
Remarks on result:
other: sorption by illite
Type:
Kd
Value:
ca. 12.01
Temp.:
25 °C
Remarks on result:
other: desorption from topsoil
Type:
Kd
Value:
ca. 265.98
Temp.:
25 °C
Remarks on result:
other: desorption from illite
Conclusions:
This study illustrated that soil and NAC type will have a significant effect on the Kd as well as the formation of acetylated metabolites.

Description of key information

According to method C.19 Koc = Pow which is available in section 4.7 (partition coefficient).


Other adsorption coefficient indicated as dimensionless:
- other: Kd ,6.38 at the temperature 25.0°C

[LogKoc: 1.65]

Key value for chemical safety assessment

Koc at 20 °C:
44.29

Additional information