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Endpoint:
adsorption / desorption, other
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Original reference is not available.
GLP compliance:
not specified
Media:
soil
Executive summary:

Paya-Perez (1991)


KOC = 10400

Endpoint:
adsorption / desorption, other
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Original reference is not available.
GLP compliance:
not specified
Executive summary:

UBA (1984)
KOC = 4300 (calculated)

Endpoint:
adsorption / desorption, other
Type of information:
other: EU Risk Assessment
Adequacy of study:
other information
Reliability:
other: EU Risk Assessment
Rationale for reliability incl. deficiencies:
other: No reliability is given as this is a summary entry for the EU RAR.
Reason / purpose for cross-reference:
reference to other study
Principles of method if other than guideline:
EU Risk Assessment
GLP compliance:
not specified

EU Risk Assessment (2003):


 



This endpoint study record was only created for further reference entries (>10) belonging to "5.4.1, rel other, EU Risk Assessment, 2003 (part 1/2)".


Executive summary:

EU Risk Assessment, 2003 (part2/2):



This endpoint study record was only created for further reference entries (>10) belonging to “5.4.1, other, EU Risk Assessment, 2003 (part 1/2)”.

Endpoint:
adsorption / desorption, other
Type of information:
other: EU Risk Assessment
Adequacy of study:
other information
Reliability:
other: EU Risk Assessment
Rationale for reliability incl. deficiencies:
other: No reliability is given as this is a summary entry for the EU RAR.
Reason / purpose for cross-reference:
reference to other study
Principles of method if other than guideline:
EU Risk Assessment
GLP compliance:
not specified

EU Risk Assessment (2003):


 


Conclusion on mobility and adsorption


1,2,4-TCB has a high adsorption capacity and the mobility in soil is expected to be low. However, because the degradation is slow in soil, 1,2,4-TCB may leach through sandy soils low in organic carbon content and reach groundwater.


_________________________________________________________________________________________________________________


 


Mobility (Leaching studies)


Mobility was studied in a soil column study on a sandy soil in a 5 cm diameter and 140 cm high soil column. The soil contained 92% sand, 2.1% clay, 0.067% organic carbon and pH was 6.4. The soil column received 14 cm water per day over 45 days with the measured concentrations 3.4 and 0.57 mg/l 1,2,4-TCB. When 3.4 mg/l was applied, 46% was leached and 54% was degraded or not accounted for. When 0.57 mg/l was applied, 39% was found in eluate and 61% was degraded or not accounted for. The amount of volatiles was not determined (Wilson et al., 1981) although other studies indicated volatility to be essential. The study indicates that 1,2,4-TCB may leach into groundwater in sandy soils with low content of organic carbon. The potential for mobility is confirmed by recoveries in groundwater surveys.


 


Adsorption


The adsorption was studied according to OECD TG 106 in three soils; alfisol clay soil (0.76% organic carbon (OC)) using the concentration range 6-25µg/l, spodosol (sandy soil, 3.56% OC) in the concentration range 7 -127µg/l and entisol (clay soil 1.11% OC). The adsorption coefficient K values were 9.7, 82 and 10.7 and the estimated Koc values were 1,300, 2,300 and 970 for alfisol, spodosol and entisol, respectively (Broecker et al., 1984).


 


Three silty clay soils are used in an adsorption study of soils with low organic carbon content (1.2, 0.11 and 0.06% OC, respectively). The initial concentrations were 0.5 -1.0 mg/l. Koc values were estimated to be 885, 2,100 and 1,300, respectively for the three soils. (Southworth and Keller, 1986). The soils were all clay soils with a clay content of 60, 86 and 68%, respectively.


 


The Freundlich adsorption constant in a peaty soil (29% organic matter ) was 241.4 resulting in a Koc of 1,441 (Friesel et al., 1984). The difference between adsorption and desorption (Kdes 200.8) indicates a high degree of reversibility of sorption.


 


In the study by Chiou et al. (1983), the adsorption was studied in a silt loam with 1.9% and a log Kom of 2.70 is presented. Recalculating Kom to Koc would result in a Koc of 864.


 


In an American study on an alluvial soil with low carbon content,the adsorption distribution constant K varied between 1.2 and 11.6 (l/kg) and the Koc values were calculated to be in the range 800 to 2,490 with the mean ± SD to be 1,460 ± 440 (Banerjee et al., 1985)


 


Other reported Koc values were 2,042 (US EPA, 1980; Howard, 1989; Calamari et al., 1983) and 1,000 (Wilson et al., 1981). Higher values of Koc have been found in the literature and using the TGD estimation (log Koc = 0.81 log Kow + 0.1) would result in Koc = 2,401.


 


A QSAR estimation performed by first order molecular connectivity index resulted in an estimated Koc of 718 (PCKOC in EPIWIN, 1995; Meylan and Howard, 1994).


 


The average Koc value from the data mentioned in this report is 1,424 and a Koc of 1,400 is used in the risk assessment estimations.

Executive summary:

EU Risk Assessment,2003:


1,2,4-TCB has a high adsorption capacity and the mobility in soil is expected to be low. However, because the degradation is slow in soil, 1,2,4-TCB may leach through sandy soils low in organic carbon content and reach groundwater.


Mobility (Leaching studies)


Mobility was studied in a soil column study on a sandy soil in a 5 cm diameter and 140 cm high soil column. The soil contained 92% sand, 2.1% clay, 0.067% organic carbon and pH was 6.4. The soil column received 14 cm water per day over 45 days with the measured concentrations 3.4 and 0.57 mg/l 1,2,4-TCB. When 3.4 mg/l was applied, 46% was leached and 54% was degraded or not accounted for. When 0.57 mg/l was applied, 39% was found in eluate and 61% was degraded or not accounted for. The amount of volatiles was not determined (Wilson et al., 1981) although other studies indicated volatility to be essential. The study indicates that 1,2,4-TCB may leach into groundwater in sandy soils with low content of organic carbon. The potential for mobility is confirmed by recoveries in groundwater surveys.


Adsorption


The adsorption was studied according to OECD TG 106 in three soils; alfisol clay soil (0.76% organic carbon (OC)) using the concentration range 6-25µg/l, spodosol (sandy soil, 3.56% OC) in the concentration range 7 -127µg/l and entisol (clay soil 1.11% OC). The adsorption coefficient K values were 9.7, 82 and 10.7 and the estimated Koc values were 1,300, 2,300 and 970 for alfisol, spodosol and entisol, respectively (Broecker et al., 1984).


Three silty clay soils are used in an adsorption study of soils with low organic carbon content (1.2, 0.11 and 0.06% OC, respectively). The initial concentrations were 0.5 -1.0 mg/l. Koc values were estimated to be 885, 2,100 and 1,300, respectively for the three soils. (Southworth and Keller, 1986). The soils were all clay soils with a clay content of 60, 86 and 68%, respectively.


The Freundlich adsorption constant in a peaty soil (29% organic matter ) was 241.4 resulting in a Koc of 1,441 (Friesel et al., 1984). The difference between adsorption and desorption (Kdes 200.8) indicates a high degree of reversibility of sorption.


In the study by Chiou et al. (1983), the adsorption was studied in a silt loam with 1.9% and a log Kom of 2.70 is presented. Recalculating Kom to Koc would result in a Koc of 864.


In an American study on an alluvial soil with low carbon content,the adsorption distribution constant K varied between 1.2 and 11.6 (l/kg) and the Koc values were calculated to be in the range 800 to 2,490 with the mean ± SD to be 1,460 ± 440 (Banerjee et al., 1985)


Other reported Koc values were 2,042 (US EPA, 1980; Howard, 1989; Calamari et al., 1983) and 1,000 (Wilson et al., 1981). Higher values of Koc have been found in the literature and using the TGD estimation (log Koc = 0.81 log Kow + 0.1) would result in Koc = 2,401.


 


A QSAR estimation performed by first order molecular connectivity index resulted in an estimated Koc of 718 (PCKOC in EPIWIN, 1995; Meylan and Howard, 1994).


The average Koc value from the data mentioned in this report is 1,424 and a Koc of 1,400 is used in the risk assessment estimations.

Endpoint:
adsorption / desorption, other
Type of information:
other: BUA report
Adequacy of study:
other information
Reliability:
other: BUA report
Rationale for reliability incl. deficiencies:
other: No reliability is given as this is a summary entry for the BUA report.
Principles of method if other than guideline:
BUA report
GLP compliance:
not specified

BUA report (1987):


 


According to OECD TG 106 following values for adsorption / desorption were found (Brocker et al., 1984):
















































soil



K



Koc



Concentration range [µg/l]



Alfisol



9,7



1300



0,14 - 3,5



Spodosol



82



2300



0,04 ¿ 0,7



Entisol



10,7



970



0,13 ¿ 3,0



Desorption: Alfisol



KDes¿ 30



 



 



Desorption: Spodosol



KDes= 130



 



 



Desorption: Entisol



KDes= 30



 



 



 


 


In another laboratory following values were found (Korte and Freitag, 1984):






























soil



A [%]



K¿



K¿OC



D1 [%]



D2 [%]



Alfisol



98,65



361



47479



0,34



0,44



Spodosol



99,50



763



21435



0,69



0,45


Executive summary:

BUA report, 1987:



According to OECD TG 106 following values for adsorption / desorption were found (Brocker et al., 1984):















































soilKKocConcentration range [µg/L]
Alfisol9.713000.14-3.5
Spodosol8223000.04-0.7
Entisol10.797000.13-3.0
Desorption: AlfisolKdes=30  
Desorption: SpodosolKdes=130  
Desorption: EntisolKdes=30  


In another laboratory following values were found (Korte and Freitag, 1984):





























SoilA [%]KKocD1 [%]D2 [%]
Alfisol998.65361474790.340.44
Spodosol99.50763214350.690.45
Endpoint:
adsorption / desorption, other
Remarks:
adsorption
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Original reference is not available.
GLP compliance:
not specified
Media:
other: sediment
Executive summary:

Schrap, 1989:


sediment:
KOC =   500
KOC =   890
KOC =  1300
KOC =  2100

Endpoint:
adsorption / desorption, other
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Original reference is not available.
GLP compliance:
not specified
Media:
other: sediment
Executive summary:

Mabey, 1982:


sediment:
KOC =  9200

Endpoint:
adsorption / desorption, other
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Original reference is not available.
GLP compliance:
not specified
Media:
other: sediment
Executive summary:

Knezovich, 1988:


sediment:
KOC =  1830 
KOC =  3030

Endpoint:
adsorption / desorption, other
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
abstract
GLP compliance:
not specified
Media:
other: soil
Executive summary:

Chin, 1988:


soil:                  
KOC =  9550

Endpoint:
adsorption / desorption, other
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Original reference is not available.
GLP compliance:
not specified
Media:
other: other
Executive summary:

Brusseau, 1990:


soil:
KOC =  780
muck:  
KOC =  530

Description of key information

For transported isolated intermediates according to REACh, Article 18, this endpoint is not a data requirement. However, data is available for this endpoint and is thus reported under the guidance of "all available data".


 


Brusseau, 1990:
soil:
KOC =  780
muck:  
KOC =  530


Chin, 1988:
soil:                  
KOC =  9550


Knezovich, 1988:
sediment:
KOC =  1830 
KOC =  3030


Mabey, 1982:
sediment:
KOC =  9200


Schrap, 1989:
sediment:
KOC =   500
KOC =   890
KOC =  1300
KOC =  2100


Paya-Perez, 1991:
KOC = 10400


UBA, 1984:
KOC = 4300 (calculated)


BUA report, 1987:
According to OECD TG 106 following values for adsorption / desorption were found (Brocker et al., 1984):















































soilKKocConcentration range [µg/L]
Alfisol9.713000.14-3.5
Spodosol8223000.04-0.7
Entisol10.797000.13-3.0
Desorption: AlfisolKdes=30  
Desorption: SpodosolKdes=130  
Desorption: EntisolKdes=30  


In another laboratory following values were found (Korte and Freitag, 1984):





























SoilA [%]KKocD1 [%]D2 [%]
Alfisol998.65361474790.340.44
Spodosol99.50763214350.690.45

EU Risk Assessment, 2003:
1,2,4-TCB has a high adsorption capacity and the mobility in soil is expected to be low. However, because the degradation is slow in soil, 1,2,4-TCB may leach through sandy soils low in organic carbon content and reach groundwater.
Mobility (Leaching studies)
Mobility was studied in a soil column study on a sandy soil in a 5 cm diameter and 140 cm high soil column. The soil contained 92% sand, 2.1% clay, 0.067% organic carbon and pH was 6.4. The soil column received 14 cm water per day over 45 days with the measured concentrations 3.4 and 0.57 mg/l 1,2,4-TCB. When 3.4 mg/l was applied, 46% was leached and 54% was degraded or not accounted for. When 0.57 mg/l was applied, 39% was found in eluate and 61% was degraded or not accounted for. The amount of volatiles was not determined (Wilson et al., 1981) although other studies indicated volatility to be essential. The study indicates that 1,2,4-TCB may leach into groundwater in sandy soils with low content of organic carbon. The potential for mobility is confirmed by recoveries in groundwater surveys.
Adsorption
The adsorption was studied according to OECD TG 106 in three soils; alfisol clay soil (0.76% organic carbon (OC)) using the concentration range 6-25µg/l, spodosol (sandy soil, 3.56% OC) in the concentration range 7 -127µg/l and entisol (clay soil 1.11% OC). The adsorption coefficient K values were 9.7, 82 and 10.7 and the estimated Koc values were 1,300, 2,300 and 970 for alfisol, spodosol and entisol, respectively (Broecker et al., 1984).
Three silty clay soils are used in an adsorption study of soils with low organic carbon content (1.2, 0.11 and 0.06% OC, respectively). The initial concentrations were 0.5 -1.0 mg/l. Koc values were estimated to be 885, 2,100 and 1,300, respectively for the three soils. (Southworth and Keller, 1986). The soils were all clay soils with a clay content of 60, 86 and 68%, respectively.
The Freundlich adsorption constant in a peaty soil (29% organic matter ) was 241.4 resulting in a Koc of 1,441 (Friesel et al., 1984). The difference between adsorption and desorption (Kdes 200.8) indicates a high degree of reversibility of sorption.
In the study by Chiou et al. (1983), the adsorption was studied in a silt loam with 1.9% and a log Kom of 2.70 is presented. Recalculating Kom to Koc would result in a Koc of 864.
In an American study on an alluvial soil with low carbon content,the adsorption distribution constant K varied between 1.2 and 11.6 (l/kg) and the Koc values were calculated to be in the range 800 to 2,490 with the mean ± SD to be 1,460 ± 440 (Banerjee et al., 1985)
Other reported Koc values were 2,042 (US EPA, 1980; Howard, 1989; Calamari et al., 1983) and 1,000 (Wilson et al., 1981). Higher values of Koc have been found in the literature and using the TGD estimation (log Koc = 0.81 log Kow + 0.1) would result in Koc = 2,401.


Key value for chemical safety assessment

Additional information