Registration Dossier

Administrative data

Endpoint:
adsorption / desorption: screening
Type of information:
other: statement
Adequacy of study:
key study
Study period:
May 2019
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods with acceptable restrictions
Cross-referenceopen allclose all
Reason / purpose:
reference to other study
Reference
Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
from 18 April 2018 to 07 May 2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
The substance can be produced through different process routes, yielding solutions in water or organic solvent (e.g. methanol or ethylene glycol).
It was initially unclear how to register the substance (mono-constituent or multi-constituent substance) and which manufactured substance to test to fulfil the REACH data requirements. After consultation with the ECHA helpdesk, the test program was started with the manufactured substance of the Lead registrant (solvent: methanol) in which the highest amount of solvent could be removed without causing degradation of the substance. This resulted in the selection of a solution of 56-57% BTMAOH in methanol as test substance.
During the course of the test program, and in order to aid meaningful risk assessment, after consultation with ECHA and upon ECHA's recommendation, it was considered to be more appropriate to test the water-based manufactured substance. As a consequence, some testing was performed with a BTMAOH solution in methanol, and some testing was performed with a BTMAOH solution in water.

The current entry reflects a test performed with a water-based test solution.
Reason / purpose:
reference to other study
Qualifier:
according to
Guideline:
EU Method A.8 (Partition Coefficient)
Version / remarks:
2016
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)
Version / remarks:
1995
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)
Version / remarks:
1996
Deviations:
no
GLP compliance:
yes
Type of method:
flask method
Partition coefficient type:
octanol-water
Analytical method:
liquid chromatography
Key result
Type:
log Pow
Partition coefficient:
-3
Temp.:
20 °C
pH:
7
Key result
Type:
Pow
Partition coefficient:
0.001
Temp.:
20 °C
pH:
7
Details on results:
- Concentration analysed in the stock solution was 1.03 g/L.
- Nominal quantity of the substance in each test sample: 2.06 mg.
- Recovery (range) for the test samples: 100-104%.
- The log Pow values were within the criterion range of ± 0.3 log units (see table below)

Table: Shake-flask results

 

Ratio
n-octanol : buffer pH 7 [v:v]

Analyzed concentration

Pow

log Pow

pH

n-octanol
[g/L]

buffer pH 7
[g/L]

individual

 

 

1:1

0.000400

0.344

1.2E-3

-2.9

7.1

 

0.000481

0.350

1.4E-3

-2.9

7.1

1:2

0.000388

0.266

1.5E-3

-2.8

7.1

 

0.000250

0.266

9.4E-4

-3.0

7.1

2:1

0.000457

0.528

8.7E-4

-3.1

7.1

 

0.000478

0.525

9.1E-4

-3.0

7.1

Mean

1.1E-3

-3.0

 

Standard deviation

2.5E-4

 

 

Conclusions:
The log Pow of BTMAOH at pH 7 and 20°C was determined to be -3.0.
Executive summary:

The shake-flask method according to EC A.8, OECD 107 and OPPTS 830.7550 was performed (GLP-study). The study was performed with 20% BTMAOH in water. Quantitative analysis was performed on BTMAOH by HPLC-UV. The Pow of BTMAOH at pH 7 and 20°C was determined to be 1.1E-3 with a standard deviation of 2.5E-4. log Pow = -3.0.

Reason / purpose:
reference to other study
Reference
Endpoint:
water solubility
Type of information:
other: visual observation and titration analysis
Adequacy of study:
key study
Study period:
August 2017
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Justification for type of information:
The substance can be produced through different process routes, yielding solutions in water or organic solvent (e.g. methanol or ethylene glycol).
It was initially unclear how to register the substance (mono-constituent or multi-constituent substance) and which manufactured substance to test to fulfil the REACH data requirements. After consultation with the ECHA helpdesk, the test program was started with the manufactured substance of the Lead registrant (solvent: methanol) in which the highest amount of solvent could be removed without causing degradation of the substance. This resulted in the selection of a solution of 56-57% BTMAOH in methanol as test substance.
During the course of the test program, and in order to aid meaningful risk assessment, after consultation with ECHA and upon ECHA's recommendation, it was considered to be more appropriate to test the water-based manufactured substance. As a consequence, some testing was performed with a BTMAOH solution in methanol, and some testing was performed with a BTMAOH solution in water.

The current entry presents data obtained with a water-based test solution.
Qualifier:
no guideline followed
Principles of method if other than guideline:
A study was not conducted because other information is available: the test item is a 20% solution in water and described as ‘Clear, almost colourless liquid’. This indicates complete dissolution of the substance at 200 g/L and therefore a test was considered not necessary. In addition, the BTMAOH content and the water content of the test item were confirmed by titration analyses (see also section 1.4).
GLP compliance:
no
Type of method:
other: visual observation and titration analysis
Key result
Water solubility:
> 200 g/L
Conc. based on:
test mat.
Temp.:
20 °C
Remarks on result:
not measured/tested
Remarks:
based on BTMAOH content (detemined by titration) in an aqueous solution with pre-defined target concentration
Details on results:
The test item is a solution of BTMAOH in water. As there was no visual observation of undissolved material in the solution, the substance is considered completely dissolved in water, and therefore the water solubility is estimated to be > 200 g/L.
Conclusions:
The water solubility of the substance is > 200 g/L.
Reason / purpose:
reference to other study
Reference
Endpoint:
pH
Type of information:
not specified
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Value taken from SDS. Test method is unknown.
Qualifier:
no guideline followed
Principles of method if other than guideline:
Test method and/or guideline(s) followed are not mentioned in the SDS.
GLP compliance:
not specified
Key result
pH value:
> 13
Concentration:
20 other: w/w%
Conclusions:
According to the SDS the pH of BTMAOH 20% in water is > 13.

Data source

Reference
Reference Type:
other company data
Title:
Unnamed
Year:
2019
Report Date:
2019

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Argumentation provided for 'testing technically not feasible' (in solutions), based on available physico-chemical properties information.
GLP compliance:
no
Type of method:
HPLC estimation method
Media:
soil/sewage sludge

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Details on test material:
Appearance: Clear almost colourless liquid
Test item storage: At room temperature
Stable under storage conditions until: 30 November 2020 (expiry date)

Study design

HPLC method

Details on study design: HPLC method:
not possible to perform (strong base, pH >13)

Results and discussion

Adsorption coefficient
Key result
Remarks on result:
not determinable because of methodological limitations

Results: HPLC method

Details on results (HPLC method):
Considering the pH of the substance in a 20% aqueous solution (pH >13), the HPLC method cannot be applied for the following reasons:
-      Potential damage of the stationary phase due to expected reaction/interaction of the ions with the stationary phase (strong base)
-      Impossible to performed the test with both ionised and non-ionised forms in appropriate buffer solutions (as > 10 % of the test compound will be dissociated within pH 5.5 to 7.5)
-      Inappropriate detection system for the anion.

Any other information on results incl. tables

In addition to above stated agrumentation for not performing HPLC screening tests, it should be noted that there is no valid QSAR model available to reliably predict Koc values for organic salt substances, so it is not possible to apply this screening option (nor details of the calculation method, or details on the applicability domain of the model).

Thus, neither technique is suited for organic salt substances (strong bases) and can therefore not be applied to provide screening information on the adsorption/desorption behaviour of the substance.

Applicant's summary and conclusion

Conclusions:
In view of the nature (organic salt) and resulting pH of the substance in solution, it is considered scientifically justified to waive testing for adsorption/desorption of this substance as it appears technically not feasible to perform either adsorption/desorption screening tests or the batch equilibrium test with BTMAOH (solutions).