Registration Dossier

Administrative data

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 physicochemical properties of the substance indicate that it can be expected to have a low potential for adsorption
Justification for type of information:
JUSTIFICATION FOR DATA WAIVING
see attached justification
Cross-referenceopen allclose all
Reason / purpose:
data waiving: supporting information
Remarks:
dispersion stability
Reference

see endpoint study record in chapter 5.6

Reason / purpose:
data waiving: supporting information
Remarks:
dispersion stability
Reference

The study of Pigment Yellow 128 according to the mentioned guideline was not possible due to its insufficient wetting with water.

→ Details refer to the endpoint 5.7

The OECD TG 318 on Dispersion Stability of Nanomaterials in Simulated Environmental Media is the first nano-specific test guideline, published 2017. Here we applied it to an organic pigment in order to map the ranges of stability in different media of surface water.

→ The study record maintained at the endpoint 5.7

Reason / purpose:
data waiving: supporting information
Remarks:
dispersion stability
Reference
Endpoint:
additional information on environmental fate and behaviour
Remarks:
Dispersion stability in simulated environmental media
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2020
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
other: OECD 318
GLP compliance:
no

The preparation of a stock solution was not successful. The resulting suspension is heterogeneous with most of the pigment accumulated in a foam-like upper phase. It is an indication that the pigment is too hydrophobic and thus it is not sufficiently wetted by water. This makes it impossible to perform all other steps in accordance to the guideline TG-318. Thus the evaluation of the stability of Pigment Yellow 128 in simulated environmental media is not possible.

Executive summary:

The study is technically not feasible.

Reason / purpose:
data waiving: supporting information
Remarks:
logKow
Reference

Estimated based on solubility ratio:

log Pow= <0 at 23°C

The Log Pow was determined following the ETAD guideline ETAD-299 based on the water solubility method OECD 105.

The test substance is almost insoluble in water as well as in n-Octanol therefore it is not possible to determine the log Pow experimentally by the shake flask method nor by HPLC method.

Reason / purpose:
data waiving: supporting information
Remarks:
logKow
Reference
Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2011
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods with acceptable restrictions
Qualifier:
according to
Guideline:
other: based on the ETAD guideline ETAD-229, which in turn is based in part on the water solubility method (shaken flask) OECD 105.
Principles of method if other than guideline:
calculation based on solubility ratio
GLP compliance:
no
Type of method:
estimation method (solubility ratio)
Partition coefficient type:
octanol-water
Analytical method:
high-performance liquid chromatography
Key result
Type:
log Pow
Partition coefficient:
< 0
Temp.:
23 °C
Remarks on result:
other: no data on pH
Details on results:
The solubilities of the pigment at 23°C are recorded below:
Solubility in water: <25 µg/L
Solubility in n-octanol: <25 µg/L

The solubility is lower the detection limit of 25 µg/L.

Estimation based on individual solubilities:

Pow= C(n-octanol) / C(water)= <25 µg/L / <25 µg/L = <1

log Pow= <0

Conclusions:
The partition coefficient of test substance was estimated to be log Pow= <0 at 23°C

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion