Reaction mass of 3-(3,3-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal and 3-(1,1-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal and 3-(1,1-dimethyl-2,3-dihydro-1H-inden-4-yl)propanal

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014-05-19 to 2014-05-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted in accordance with relevant test method and in compliance with GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

yes

Remarks:

Measured concentration differed by 17.6% . The deviation was accepted because the analytical method, including critical liquid and extraction were assumed to have an extended uncertainty.

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

yes

Remarks:

Measured concentration differed by 17.6% . The deviation was accepted because the analytical method, including critical liquid and extraction were assumed to have an extended uncertainty.

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of inspection: 2013-06-03/05, Date of signature: 2013-11-05

Type of method:

flask method

Specific details on test material used for the study:

- Stability under test conditions: Hydrolytically stable at pH 7 and reduced oxygen conditions (NOACK lab study code 140324FZ/CPH15825)

Water solubility:

50.8 mg/L

Temp.:

20 °C

pH:

8

Remarks on result:

other: Isomer 1: 3-(3,3-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal has a water solubility value of approximately 51 mg/l

Water solubility:

40.8 mg/L

Temp.:

20 °C

pH:

8

Remarks on result:

other: Isomer 2: 3-(1,1-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal has a water solubility value of approximately 41 mg/l

Water solubility:

3.34 mg/L

Temp.:

20 °C

pH:

8

Remarks on result:

other: Isomer 3: 3-(1,1-dimethyl-2,3-dihydro-1H-inden-4-yl)propanal has a water solubility value of approximately 3.3 mg/l

Details on results:

Method validation:

Linearity:
The analytical system gave a linear response in the range of 5 -100 µg/l. Single determination of 7 standard concentrations were made. The coefficient of regression (r2) of the calibration curve was >0.992. The system quantification limit for the analyte was set to 5 µg/l based on the calibration and requirements of the study. A S/N of >11 was provided and verified by limit of detection (LOD) determination. The LOD was determined to be 2 µg/l confirmed by a signal-to-noise ratio (S/N) of at least 6.

Limit of Quantification (LOQ):
The LOQ was defined as 10 µg/l and checked by means of accuracy.

Accuracy and precision:
Mean recovery rates were 92% for the 1xLOQ and 95% for the 5xLOQ, indicating sufficient accuracy of the analytical method.
In addition, the precision of both fortification levels was satisfying with a coefficient of determination of ≤3.2%.

Specificity:
Response of blank samples were significantly lower than 30% of LOQ. Analyses were performed with GC-MS as selective detector. At least three specific ions (ideally with an m/z ratio of >100) were taken for quantification. The spectra of sample peaks were compared against spectra obtained from standards.

Preliminary study:

The water solubility determined was in the range of 102 mg/l resulting in an application dose of 500 mg/l as a fivefold of the expected solubility.

pH check

The measured pH value of test mixture was 8 at any sampling interval (24, 48, 72h) and for both replicates.

Tyndall effect check

Negative at all sampling times.

Water solubility results

Water solubility result at 20°C for test sample (sum of three isomers)

Sample	Replicate No	Concentration^2(mg/l)	Mean (mg/l)
24 h	1	102	101
	2	99.0
48 h	1	99.7	98.9
	2	98.0
72 h	1 2	89.6 81.4	85.5
mean (24 – 72 h)			95.0
Deviation[%]^1			17.6

1 calculated

2 calculated from triplicate samples

Isomer ratio [%]: determined by relative proportion of each isomer by peak area

	[%]
Sample	24 h		48 h		72 h		Mean^1
Replicate	1	2	1	2	1	2
Isomer 1	53.3	53.0	53.2	53.9	53.9	53.9	53.5
Isomer 3	3.46	3.46	3.37	3.52	3.64	3.64	3.52
Isomer 2	43.2	43.5	43.4	42.6	42.5	42.5	43.0
sum	100	100	100	100	100	100	100

 

Isomer ratio [mg/l]: determined by relative proportion of each isomer by peak area

	[mg/l]
Sample	24 h		48 h		72 h		Mean^1
Replicate	1	2	1	2	1	2
Test item	102	99.0	99.7	98	89.6	81.4	95.0
Isomer 1	54.4	52.5	53.0	52.8	48.3	43.9	50.8
Isomer 3	3.53	3.43	3.36	3.45	3.26	2.96	3.34
Isomer 2	44.1	43.1	43.3	41.7	38.1	34.6	40.8

1 Mean value of 24 – 72 h

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)

Executive summary:

The water solubility of the individual constituents of the test substance was determined using a relevant test method.

The result is considered to be reliable.

Description of key information

Water Solubility: Isomer 1: 3-(3,3-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal: 51 mg/L

Water Solubility: Isomer 2: 3-(1,1-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal: 41 mg/L

Water Solubility: Isomer 3: 3-(1,1-dimethyl-2,3-dihydro-1H-inden-4-yl)propanal: 3.3 mg/L

Additional information

The water solubility of the submission substance was determined using the flask method in accordance with OECD 105 and EU Method A.6 and in compliance with GLP.

For environmental exposure assessment, the water solubility of each individual isomer is relevant. Therefore, the water solubility at 20±0.5°C and pH 8 of each isomer of the submission substance was also determined and qualified based on peak area distribution as follows:

Isomer 1: 3-(3,3-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal: 51 mg/L

Isomer 2: 3-(1,1-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal: 41 mg/L

Isomer 3: 3-(1,1-dimethyl-2,3-dihydro-1H-inden-4-yl)propanal: 3.3 mg/L