Potassium (S)-lactate

Viscosity

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

viscosity

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Temp.:

other: 25 °C

Parameter:

dynamic viscosity (in mPa s)

Value:

33.46

Remarks on result:

other: Dynamic viscosity for 70 % (w/w) aqueous solution.

Additional aqueous solutions of potassium lactate investigated:

% (w/w) potassium lactate	dynamic viscosity [mPa*s]
1%	0.9
2%	1
5%	1
10%	1.1
20%	1.5
30%	2.1
40%	3.3
50%	5.5
60%	11.3

Conclusions:

The dynamic viscosities of different concentrated aqueous solutions of potassium lactate were determined by the capillary method:
1 % (w/w) potassium lactate in water: η = 0.9 mPa × s;
2 % (w/w) potassium lactate in water: η = 1 mPa × s;
5 % (w/w) potassium lactate in water: η = 1 mPa × s;
10 % (w/w) potassium lactate in water: η = 1.1 mPa × s;
20 % (w/w) potassium lactate in water: η = 1.5 mPa × s;
30 % (w/w) potassium lactate in water: η = 2.1 mPa × s;
40 % (w/w) potassium lactate in water: η = 3.3 mPa × s;
50 % (w/w) potassium lactate in water: η = 5.5 mPa × s;
60 % (w/w) potassium lactate in water: η = 11.3 mPa × s;
70 % (w/w) potassium lactate in water: η = 33.5 mPa × s.

Executive summary:

In this experimental study, which is comparable to an OECD 114 study (capillary method), the dynamic viscosities of different aqueous solutions of potassium lactate were determined. Crystalline potassium lactate is hygroscopic and extremely difficult to isolate, thus only manufactured and marketed as a concentrated aqueous solution. Consequently, the following dynamic viscosities for the different potassium lactate concentrations in water were determined at 25°C:

The dynamic viscosities of different concentrated aqueous solutions of potassium lactate were determined by the capillary method:

1 % (w/w) potassium lactate in water: η = 0.9 mPa × s;

2 % (w/w) potassium lactate in water: η = 1 mPa × s;

5 % (w/w) potassium lactate in water: η = 1 mPa × s;

10 % (w/w) potassium lactate in water: η = 1.1 mPa × s;

20 % (w/w) potassium lactate in water: η = 1.5 mPa × s;

30 % (w/w) potassium lactate in water: η = 2.1 mPa × s;

40 % (w/w) potassium lactate in water: η = 3.3 mPa × s;

50 % (w/w) potassium lactate in water: η = 5.5 mPa × s;

60 % (w/w) potassium lactate in water: η = 11.3 mPa × s;

70 % (w/w) potassium lactate in water: η = 33.5 mPa × s.

This information is used in a read-across approach in the assessment of the target substance. For justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reference 2

Endpoint:

viscosity

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is a solid

Description of key information

In this experimental study, which is comparable to an OECD 114 (capillary method), the dynamic viscosities of different aqueous solutions of potassium lactate have been determined. Crystalline potassium lactate is hygroscopic and extremely difficult to isolate, thus only manufactured and marketed as a concentrated aqueous solution.

As a result the following dynamic viscosities for the different potassium lactate concentrations in water have been determined at 25 °C:

1 % (w/w) potassium lactate in water: η = 0.9 mPa*s;

2 % (w/w) potassium lactate in water: η = 1 mPa*s;

5 % (w/w) potassium lactate in water: η = 1 mPa*s;

10 % (w/w) potassium lactate in water: η = 1.1 mPa*s;

20 % (w/w) potassium lactate in water: η = 1.5 mPa*s;

30 % (w/w) potassium lactate in water: η = 2.1 mPa*s;

40 % (w/w) potassium lactate in water: η = 3.3 mPa*s;

50 % (w/w) potassium lactate in water: η = 5.5 mPa*s;

60 % (w/w) potassium lactate in water: η = 11.3 mPa*s;

70 % (w/w) potassium lactate in water: η = 33.5 mPa*s.

The aqueous Potassium-(S)-lactate solution placed on the market has a concentration of approximately 60–78 % (w/w). Derived from the results mentioned above, the dynamic viscosity of an aqueous solution of the target substance in this concentration range is approximately the same. Futhermore, derived from an extrapolation approach, it can be stated that higher concentrated solutions have higher dynamic viscosities.

Key value for chemical safety assessment

Viscosity:

33.46 mPa · s (dynamic)

at the temperature of:

25 °C