Cyanamide

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1990-01-08

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: CIPAC Guideline MT 157.2

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

> 800 g/L

Temp.:

20 °C

pH:

3.8

Water solubility:

> 560 g/L

Temp.:

20 °C

pH:

7

Water solubility:

> 530 g/L

Temp.:

20 °C

pH:

> 9 - < 11

Details on results:

Due to the high water solubility of the tets item Cyanamid F1000 (850 g/L as given by the manufacturer), even with the lowest quantity of water (40 mL as required by the guideline), a mixture of approx. 400 g Cyanamid F1000 with 40 mL water had to be prepared. At such a high concentration and test temperature of 30 °C the exothermic formation of Dicyandiamide is possible. A further reaction to Melamine may also occur. It is thus not possible to determine the saturation concentration at equilibrium, also taking into account safety aspects regarding the laboratory personnel.
From the density calibration curve, it can be seen, that the water solubility of Cyanamid F1000 at 20 °C and pH 3.8 is greater than 800 g/L.
It is known from the literature that there is a dimerization of cyanamide to dicyandiamine at pH values > 5 and a hydrolysis to urea at pH values < 3.8.

Conclusions:

The water solubility of the test item is greater than 800 g/L at 20 °C and pH 3.8.

Executive summary:

A determination of the water solubility of Cyanamid F1000 with the flask method as described in the CIPAC MT 157.2 was attempted. Due to the high water solubility of the compound (850 g/L as given by the manufacturer), even with the lowest quantity of water (40 mL as required by the guideline), a mixture of appro. 400 g Cyanamid F1000 with 40 mL water had to be prepared. At such a high concentration and test temperature of 30 °C the exothermic formation of Dicyandiamide is possible. A further reaction to Melamine may also occur. It is thus not possible to determine the saturation concentration at equilibrium. Results of the preliminary test showed that at pH 7: > 560 g/L and at pH 9-11: > 530 g/L (at 20 °C), but it is known from the literature that there is a dimerization of cyanamide to dicyanamide at pH values > 5 and a hydrolysis to urea at pH values < 3.8. From the density calibration curve, it could be seen, that the water solubility of Cyanamid F1000 at 20 °C and pH 3.8 is greater than 800 g/L. Cyanamid F1000 is therefore considered as very soluble (> 10000 mg/L).

Description of key information

The water solubility of the test item is greater than 800 g/L at 20 °C and pH 3.8.

Key value for chemical safety assessment

Water solubility:

800 g/L

at the temperature of:

20 °C

Additional information

A determination of the water solubility of Cyanamid F1000 with the flask method as described in the CIPAC MT 157.2 was attempted. Due to the high water solubility of the compound (850 g/L as given by the manufacturer), even with the lowest quantity of water (40 mL as required by the guideline), a mixture of appro. 400 g Cyanamid F1000 with 40 mL water had to be prepared. At such a high concentration and test temperature of 30 °C the exothermic formation of Dicyandiamide is possible. A further reaction to Melamine may also occur. It is thus not possible to determine the saturation concentration at equilibrium. Results of the preliminary test showed that at pH 7: > 560 g/L and at pH 9-11: > 530 g/L (at 20 °C), but it is known from the literature that there is a dimerization of cyanamide to dicyanamide at pH values > 5 and a hydrolysis to urea at pH values < 3.8. From the density calibration curve, it could be seen, that the water solubility of Cyanamid F1000 at 20 °C and pH 3.8 is greater than 800 g/L. Cyanamid F1000 is therefore considered as very soluble (> 10000 mg/L).