1,3-dibutyl-2-thiourea

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Specific details on test material used for the study:

None.

Key result

Water solubility:

212 mg/L

Conc. based on:

act. ingr.

Loading of aqueous phase:

4 g/L

Incubation duration:

72 h

Temp.:

20 °C

pH:

5

Details on results:

Test item concentrations determined in samples are presented in Table 1. The test item concentrations in filtered, centrifuged and centrifuged then filtered samples are not significantly different, but samples centrifuged then filtered did not contain any undissolved particles. These samples were thus considered for calculation. Results are presented in table1. As specified in the OECD 105 guideline, the saturation equilibrium was reached: the concentrations measured in at least the two last vessels did not differ by more than 15%, all three samples were thus considered for the final calculation. The temperature in the test systems was monitored during the test, it was remained between 19.9°C and 20.0°C throughout the experiment (mean 19.9°C).

Table1Definitive test: test item determinations

 

Time point (hours)	Control concentration	Test item concentration (g/L)	Difference from previous time point (%)*	Overall Mean Measured Test Item (g/L)
24	<DL	Filtered sample : 0.216	NA	0.212
		Centrifuged sample: 0.221
		Centrifuged & filtered sample: 0.214
48	<DL	Centrifuged & filtered sample: 0.217	1.4%
72	<DL	Centrifuged & filtered sample: 0.206	-5.1%

*only the centrifuged & filtered sample was considered

NA Not Applicable

< DL (0.0028 mg/L): concentration lower than the Detection Limit of the analytical method

< QL (0.0093 mg/L): concentration lower than the Quantification Limit of the analytical method

Conclusions:

Water solubility of 1,3-dibutyl-2-thiourea is 212 mg/L.

Executive summary:

The solubility of 1,3 -dibutyl-2 -thiourea was determined according to the OECD 105 guideline, shake-flask method. Three replicate samples of test item (around 1 g) dissolved in ultrapure water were prepared into glass flasks (250 mL of capacity, theoretical concentration of 4 g/L). Samples were diluted with ultrapure and shaken during 5 min, then test vessels were capped and placed in an oven operating at ca 30°C under continuous stirring (with a magnetic stir bar). Three additional glass flasks containing only ultrapure water were also placed within the same conditions (control samples). After ca 24 hours at 30°C, 1 test item sample and 1 control sample were transferred in an oven operating at ca 20°C (agitation was stopped). After 24h, and due to the presence of undissolved test item, an aliquot of the supernatants was filtered through 0.8 and 0.8 µm filters, 1 aliquot was centrifuged (2000 g / 12 minutes) and 1 aliquot was centrifuged then filtered: clear solutions of all samples were analysed according to the available analytical procedure. This protocol was applied to dispose of undissolved particles. The other samples after 48 and 72 days were only centrifuged then filtered. The pH of test item samples were assessed after a cooling period (pH strips); the temperature in the oven was monitored during the whole test. 1,3-dibutylthiourea was analysed with UPLC/MS. Variation on a set of repeated measurements was 0.62% (repeatability). LOQ was 9 µg/L and LOD was 3 µg/L.

The test item concentrations in filtered, centrifuged and centrifuged then filtered samples were not significantly different, but samples centrifuged then filtered did not contain any undissolved particles. These samples were thus considered for calculation. As specified in the OECD 105 guideline, the saturation equilibrium was reached: the concentrations measured in at least the two last vessels did not differ by more than 15%, all three samples were thus considered for the final calculation. The temperature in the test systems was monitored during the test, it was remained between 19.9°C and 20.0°C throughout the experiment (mean 19.9°C). pH was between 4.5 and 5.5

Water solubility of 1,3-dibutyl-2-thiourea is 212 mg/L.

Description of key information

The solubility of 1,3-dibutyl-2-thiourea was determined according to the OECD 105 guideline, shake-flask method. Three replicate samples of test item (around 1 g) dissolved in ultrapure water were prepared into glass flasks (250 mL of capacity, theoretical concentration of 4 g/L). Samples were diluted with ultrapure and shaken during 5 min, then test vessels were capped and placed in an oven operating at ca 30°C under continuous stirring (with a magnetic stir bar). Three additional glass flasks containing only ultrapure water were also placed within the same conditions (control samples). After ca 24 hours at 30°C, 1 test item sample and 1 control sample were transferred in an oven operating at ca 20°C (agitation was stopped). After 24h, and due to the presence of undissolved test item, an aliquot of the supernatants was filtered through 0.8 and 0.8 µm filters, 1 aliquot was centrifuged (2000 g / 12 minutes) and 1 aliquot was centrifuged then filtered: clear solutions of all samples were analysed according to the available analytical procedure. This protocol was applied to dispose of undissolved particles. The other samples after 48 and 72 days were only centrifuged then filtered. The pH of test item samples were assessed after a cooling period (pH strips); the temperature in the oven was monitored during the whole test. 1,3-dibutylthiourea was analysed with UPLC/MS. Variation on a set of repeated measurements was 0.62% (repeatability). LOQ was 9 µg/L and LOD was 3 µg/L.

The test item concentrations in filtered, centrifuged and centrifuged then filtered samples were not significantly different, but samples centrifuged then filtered did not contain any undissolved particles. These samples were thus considered for calculation. As specified in the OECD 105 guideline, the saturation equilibrium was reached: the concentrations measured in at least the two last vessels did not differ by more than 15%, all three samples were thus considered for the final calculation. The temperature in the test systems was monitored during the test, it was remained between 19.9°C and 20.0°C throughout the experiment (mean 19.9°C). pH was between 4.5 and 5.5

Water solubility of 1,3-dibutyl-2-thiourea is 212 mg/L.

Key value for chemical safety assessment

Water solubility:

212 mg/L

at the temperature of:

20 °C