Sodium formate

Adsorption / desorption

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

adsorption / desorption: screening

Type of information:

calculation (if not (Q)SAR)

Remarks:

Scientifically acceptable calculation method

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

no guideline followed

Principles of method if other than guideline:

Calculation method determining the Koc for charged molecules.

GLP compliance:

no

Type of method:

other: calculation of log Koc for ionized molecule

Media:

soil/sewage sludge

Type:

Koc

Value:

31 L/kg

Type:

log Koc

Value:

1.49 L/kg

The data refer to the charged molecule.

Validity criteria fulfilled:

not applicable

Conclusions:

The Koc and Log Koc of formic acid were calculated to be 31 and 1.49 respectively.

Executive summary:

Based on a Log Pow value of -0.46 and a pKa value of 3.70, the Koc and Log Koc of formic acid were reliably calculated to be 31 and 1.49, respectively (Franco and Trapp, 2008; BASF SE, 2009).

Reference 2

Endpoint:

adsorption / desorption, other

Type of information:

(Q)SAR

Adequacy of study:

other information

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Generally scientifically accepted method, but EPI Suite not validated for inorganic salts

Principles of method if other than guideline:

PCKOC (v1.66)

Type of method:

other: calculated

Media:

soil

Test temperature:

25 °C

Type:

Koc

Value:

1 L/kg

Remarks on result:

other: PCKOC (v1.66) QSAR calculation based on MCI Method

Koc may be sensitive to pH.

Validity criteria fulfilled:

not applicable

Conclusions:

A Koc value of 1.00 L/Kg was estimated for sodium formate by the PCKOC (v1.66) QSAR in the EPISuite (v3.12) software based on the MCI Method.

Executive summary:

A Koc value of 1.00 L/Kg was estimated for sodium formate by the PCKOC (v1.66) QSAR in the EPISuite (v3.12) software based on the MCI Method. However, this Koc value is not assignable since EPISuite is not validated for inorganic salts.

Reference 3

Endpoint:

adsorption / desorption: screening

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance has a low octanol water partition coefficient and the adsorption potential of this substance is related to this parameter

the study does not need to be conducted because the substance and its relevant degradation products decompose rapidly

Justification for type of information:

In accordance with column 2 of REACH Annex VIII, the study does not need to be conducted since sodium formate is readily biodegradable (KM Lab, 1998) and has a low potential for adsorption due to high water solubility coupled with a very low octanol-water partition coefficient (log Kow <-1.8, Perstorp, 2009).

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

data waiving: supporting information

Reference 4

Endpoint:

adsorption / desorption: screening

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

It is considered appropriate to address the adsorption/desorption data requirement for potassium formate by read-across to an available reliable calculation on formic acid.
Sodium formate is the sodium salt of formic acid, and will dissociate immediately in aqueous and biological surroundings to the formate ion. It is therefore expected that the environmental profile of formic acid and sodium formate will be similar.

Reason / purpose for cross-reference:

read-across: supporting information

Specific details on test material used for the study:

Formic acid is being used as a read-across for sodium formate.

Type:

Koc

Value:

31 L/kg

Type:

log Koc

Value:

1.49 L/kg

The data refer to the charged molecule.

Validity criteria fulfilled:

not applicable

Conclusions:

The Koc and Log Koc of formic acid were calculated to be 31 and 1.49 respectively, and are considered suitable for read-across to sodium formate.

Executive summary:

It is considered appropriate to address the adsorption/desorption data requirement for sodium formate by read-across to an available reliable calculation on formic acid. Sodium formate is the sodium salt of formic acid, and will dissociate immediately in aqueous and biological surroundings to the formate ion. It is therefore expected that the environmental profile of formic acid and sodium formate will be similar.

 

Based on a Log Pow value of -0.46 and a pKa value of 3.70, the Koc and Log Koc of formic acid were reliably calculated to be 31 and 1.49, respectively (Franco and Trapp, 2008; BASF SE, 2009). These values are therefore also considered for sodium formate.

Description of key information

In accordance with column 2 of REACH Annex VIII, the study does not need to be conducted since sodium formate is readily biodegradable (KM Lab, 1998) and has a low potential for adsorption due to high water solubility coupled with a very low octanol-water partition coefficient (log Kow = -0.47; US EPA, 2006). Adsorption to the solid soil phase is therefore not expected.

Additional information

A read across was performed to formic acid in order to have a reliable value for the calculation of PNECsed and PNECsoil via the equilibrium partitioning method.

The Koc and log Koc of the dissociated, charged form at realistic environmental pH values was calculated by using the pKa (= 3.70) and the logPow of the uncharged molecule (= -0.46) for a corrected logKoc according to Franco et al. (2008). For the formate ion which will be present at environmental relevant pH values, slightly higher adsorption rates were estimated (Koc = 31, log Koc = 1.49) (BASF SE, 2009).