4-chlorobenzoic acid

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2021-05-10 - 2021-05-31

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

1995

Deviations:

not specified

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

not specified

GLP compliance:

no

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

4-chlorobenzoic acid

EC Number:

200-805-9

EC Name:

4-chlorobenzoic acid

Cas Number:

74-11-3

Molecular formula:

C7H5ClO2

IUPAC Name:

4-chlorobenzoic acid

Test material form:

solid: particulate/powder

Details on test material:

white to yellowish crystalline powder

Results and discussion

Water solubility

Key result

Water solubility:

74.9 mg/L

Conc. based on:

test mat. (dissolved fraction)

Loading of aqueous phase:

51 g/L

Incubation duration:

3 d

Temp.:

20 °C

pH:

>= 3.7 - <= 3.8

Any other information on results incl. tables

Preliminary Test

The preliminary test at room temperature showed, that the water solubility of the test item was between 10.4 mg/L and 65.7 mg/L.

Table 5:    Preliminary test for the water solubility

Amount of test item [mg]	Added volume of water [mL]	Ultrasonic bath [h:min]	Remark
100.71	0.1	--	not dissolved
	0.6	--	not dissolved
	1,6	0:03	not dissolved
	3.6	0:03	not dissolved
	13.6	0:05	not dissolved
	100	0:08	not dissolved
6.57	100	18:25^1)	not dissolved
2.60	250	18:25^1)	dissolved
3.03	500	18:25^1)	dissolved

¹⁾Stirring time at room temperature

The solubility of the test item in water at room temperature was estimated to be> 10.4 mg/L and < 65.7 g/L. Therefore, the flask method was performed.

Main Test (flask method)

For the main test three flasks were prepared with an amount of test item and water, and one flask only with water (blank). After stirring and centrifugation the aqueous phases were measured by means of HPLC. The solution of each flask has been measured twice.

Table 6:    Results of the flask method

Flask	1b	2a	3a	4a
measured value [mg/L]	14.95 / 14.85	15.09 / 15.12	14.87 / 14.97	0 / 0
aliquot of the flask [mL]	0.2	0.2	0.2	0.2
total volume after dilution [mL]	1	1	1	1
water solubility [mg/L]	74.8 / 74.3	75.4 / 75.6	74.3 / 74.8	0 / 0
average water solubility [mg/L]	74.5	75.5	74.6	0
mean value of the water solubility [mg/L]	74.9			0
standard deviation [mg/L]	0.6			--
relative standard deviation [%]	0.7			--

To verify the accuracy of the analytical method a fresh prepared standard solution (prepared with the test item) was measured in between the samples of the flask method.

Table 7: Measurement of a standard solution

Standard solution (nominal value [mg/L])	Measured value [mg/L]	Repeatability [%]
Ü1 (6.95)	6.88	99.0
	7.06	101.5
Ü2 (7.93)	7.98	100.7
	7.98	100.7

The recovery rate of the measured standard solutions was in the range from 99.0 % to 101.5 %, which shows a good accuracy of the analytical method

Applicant's summary and conclusion

Conclusions:

The water-solubility of 4-chlorobenzoic acid using the flask-method was determined to be 74.9 mg/L at 20°C.

Executive summary:

According to OECD Test Guideline 105 (1995) and Regulation (EC) No 440/2008 Method A.6. the water solubility at 20 °C of the test item 4 -Chlorobenzoic acid was determined to be:

c_S = 74.9 mg/L, RSD = 0.7 %