2-Propanol, 1-amino-, compds. with polyethylene glycol hydrogen sulfate C12-14-alkyl ethers

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30 AUG - 02 SEP 1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all concentrations at 0 and 72 h.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution was prepared by adding 105 mg test substance to 1 L deionised water. The stock solution was diluted with dionised water to give the respective test concentrations.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: 86.81 SAG
- Source (laboratory, culture collection): originally obtained from Institut für Wasser-, Boden- und Lufthygiene, Berlin, Germany and subsequently in-house breeding
- Age of inoculum (at test initiation): 3 days

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

24 +/- 2 °C

pH:

Test start: 8.4 - 8.5
Test end: 7.6 - 9.4

Nominal and measured concentrations:

nominal: 1, 2, 4, 8, 16 and 32 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flasks
- Initial cells density: 20000 cells/mL
- Control end cells density: 970000
- No. of vessels per concentration (replicates): 5
- No. of vessels per control (replicates): 8


OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Photoperiod: continuous illumination
- Light intensity and quality: approximately 8000 Lux, white


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: photometrically at 685 nm

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

14 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

4.3 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

2 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Reported statistics and error estimates:

From the comparison of the areas under the growth curves, the percentage inhibition rates are calculated for each concentration.
The expect probits for each concentration were calculated by probit transformation of the percentage inhibition rates over the regression line. This probits are the basis for the following probit analysis according to Cavalli-Sforza.

Table 1: Mean cell numbers

	Cell number (x 10^4cells/mL)
Concentration [mg/L]	Test period (h)
	0 h	24 h	48 h	72 h
Control	2	6	25	97
1	2	7	25	93
2	2	8	25	83
4	2	6	23	77
8	2	6	16	49
16	2	4	7	11
32	2	3	4	3

Table 2: Analytically determined test concentrations

Nominal concentration	0 h	48 h	Concentration for biological valuation [mg/L]
Control	0	0	0
1	1.1	1.2	1
2	2.0	2.1	2
4	3.9	4.1	4
8	8.0	8.6	8
16	16.1	16.8	16
32	32.6	32.9	32
Stock solution	107	110	100

Validity criteria fulfilled:

not specified

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

(e.g. non-GLP study; no analytical verification of the test concentrations)

Qualifier:

according to guideline

Guideline:

other: German industrial standard test guideline DIN 38412, part 9

GLP compliance:

no

Analytical monitoring:

no

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

15.1 mg/L

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC20

Effect conc.:

19.7 mg/L

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

32.7 mg/L

Basis for effect:

growth rate

Effect values related to nominal concentration of the test substance.

Effect values (endpoint: biomass):
E_bC₁₀ (72 h) = 14.9 mg/L
E_bC₂₀ (72 h) = 17.9 mg/L
E_bC₅₀ (72 h) = 25.4 mg/L

pH:

Concentration [mg/L]	uninoculated		inoculated
	0 h	72 h	72 h
Control	8.2	8.12	9.60
7.812	8.68	8.06	9.44
15.625	8.87	8.09	9.18
31.25	9.21	8.18	8.36
62.5	9.45	8.33	8.38
125	9.69	8.54	8.75
250	9.92	8.80	8.80
500	10.24	9.04	9.03
62.5*	8.25	8.02	8.50
500*	8.08	8.00	8.05

* = neutralised samples

Inhibition may be partly due to the basic pH of the test substance:
- inhibition of the fluorescence after 72 h compared to a control:

Sample	Inhibition [%]
62.5 mg/L	94.8
62.5 mg/L (neutralized)	62.2
500 mg/L	100.0
500 mg/L (neutralized)	94.6

Validity according to OECDTG201 (adopted 23Mar2006):

(1) The factor of cell number measured in the control between 0 and 72 h was 42.1, which is > 16. The test fulfils this validity criterion.

(2) Evaluation of the sectional growth rates (the mean coefficient of variation of sectional growth rates calculated for the individual control replicates must not be higher than 35 %): Coefficients of variation in control replicates from 0 to 72 h were: Replicate 1: 5.9 %; Replicate 2: 7.9%; Replicate 3: 8.6 %; Replicate 4: 12.6 %. The mean of the replicate coefficients of variation in the section-by-section growth rate was:8.7%. Regarding the test period of72 h; the test fulfils this validity criterion.

(3) The coefficient of variation of average specific growth rates in control cultures was 0.7 % after 72 h, which is 7%. The test fulfils this validity criterion

Description of key information

ErC50 (72 h): 14 mg a.i./L (nominal, OECD 201)

NOErC (72 h): 2 mg a.i../L (nominal, OECD 201)

Additional information

The toxicity of Alcohols, C12-14 (even numbered), ethoxylated (<=2.5 moles EO), sulfated, monoisopropanolamine salt to algae was tested in a GLP guideline study according to OECD 201. Green algae (Desmodesmus subspicatus) were exposed to nominal test substance concentrations of 1, 2, 4, 8, 16 and 32 mg/L for 72 h. The test concentrations were analytically verified using the MBAS assay (methylene blue active substances assay). All measured concentrations were >80% of nominal. Based on the algal growth rate an EC50 of 14 mg a.i./L was recorded. The EC10 (72 h) was 4.3 mg a.i./L.

 

In a study performed according to German standard DIN 38412, part 9, the toxicity of monoisopropanolamine (MIPA) to algae was investigated. The determined ErC50 was 32.7 mg/L (72-h ErC10 = 15.1 mg/L). The test was performed without neutralisation of the test concentrations.