Atrazine

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 14 June 1993 to 13 October 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

not specified

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EPA OPP guidelines 63-8

Deviations:

yes

Remarks:

the water solubility test was performed in distilled water only and at 20°C only

Principles of method if other than guideline:

The PKa value is so low (1.56) that the water solubility test was performed in distilled water only and not using buffers at 3 pH values (4, 7, 9) since the atrazine molecule would be in the same form at all these pH's and solubility would not be effected. In addition the preliminary work indicated a water solubility of 4.04x10^-2 g/l at 30°C and hence a solubility temperature dependence of less than 3% per °C compared to the 20°C result. Therefore the test was performed at 20°C only and not at two other temperatures at least 10°C above and 20°C below of the test temperature.

GLP compliance:

yes

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

Atrazine

EC Number:

217-617-8

EC Name:

Atrazine

Cas Number:

1912-24-9

Molecular formula:

C8H14ClN5

IUPAC Name:

6-chloro-N2-ethyl-N4-(propan-2-yl)-1,3,5-triazine-2,4-diamine

Details on test material:

Atrazine (pure grades)
Batch number 744
Purity 99.5%
Expiry: Stable until at least January 2995
Storage 4°C
Appaerance: white powder

Results and discussion

Water solubility

Water solubility:

0.032 g/L

Temp.:

20 °C

pH:

8.07 - 8.46

Details on results:

The water solubility results (uncorrected for purity) rangs from 0.03115 to 0.03351 g/L and pH from 8.07 to 8.46.
The mean water solubility was determined as 0.03193 g/L (corrected for purity) with an associated standard deviation of 8.75 x 10^-4 g/L

Applicant's summary and conclusion

Conclusions:

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