Reaction mass of 2-(3-{6-[3-(2-Hydroxyethyl)-3-methylureido]hexyl}-1-methylureido)ethanol and 6-[3-(2-Hydroxyethyl)-3-methylureido]hexylamino 3-(methylamino)propionate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

at time 0 and time 72.

Vehicle:

no

Details on test solutions:

Range of concentrations, nominally 0.88, 1.9, 4.3, 9.4, 20.7, 45.5 and 100 mg/L
A stock solution was prepared to give the desired series of test concentrations. 100.8 mg of the test item were added to 1 litres of dilution water, treated for 1 h in an ultrasonic bath and stirred for 24 h on a magnetic stirrer. The pH was measured to be 8.1.
To produce the different test item concentrations appropriate amounts of the stock solution were diluted with dilution water to a volume of 100 mL and 0.769 mL of the algal inoculum was added to each replicate resulting in a final cell density of 5000 cells/mL. For each test item concentration and the control 3 replicates were prepared. All flasks were sealed with cotton stoppers.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

Desmodesmus subspicatus (formerly Scene-desmus subspicatus) Strain No. 86.81 SAG
Source : Strain of the test species obtained from 'The Collection of Algal Cultures' of the Institute of Plant Physiology at the University of Göttingen (Germany).

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

21-24°C

pH:

time 0h:7.9 to 8.0
time 72h: 8.9 to 9.1

Salinity:

Nutrient medium according to guideline was used.

Nominal and measured concentrations:

Measured = nominal

Details on test conditions:

Exponentially growing stock cultures were maintained in the test facility under constant temperature conditions (21 - 24 °C with a maximum fluctuation of +/- 2 °C) at a light intensity in the range 60 to 120 μE x m-2 x s-1 (measured in the range 400 to 700 nm using a spherical quantum flux meter). The growth medium (according to BRINGMANN & KÜHN (1977) was renewed once a week. Cell density measurements were made using a microcell counter, Sysmex F300, Digitana.

Pre cultures were set up three days before the start of a test. They were grown under identical exposure conditions as the stock cultures, except from the use of a different growth medium

The algal inocula for the test were taken from an exponentially growing pre culture and were mixed with the growth medium (annex 1) to make up to a final cell density of about 5000 cells per millilitre in the test medium.

Reference substance (positive control):

no

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

- Exponential growth in the control (for algal test): yes
The results are expressed in terms of nominal concentrations. Effective concentrations ranged from 100 % to 102 % of nominal values at 0 hours, and from 93 % to 102 % of nominal values at 72 hours. Thus, nominal and measured concentrations are considered identical.

Results of HPLC analysis

Conc. (mg/L	HPLC results (0h)	HPLC results (72h)
Control	n.d.	<0.858
1.9	1.92	1.77
20.7	21.0	21.1
100	99.9	99.9

Validity criteria fulfilled:

yes

Remarks:

Biomass in the control (0-72h):141 (criterion 16) Mean of variation in the section-by-section growth rate: 15.8%. (criterion: <35 %) Coefficient of variation of the mean specific growth rate replicates in the control (0-72h): 0.9%. (criterion: <7%). .

Conclusions:

No toxicity of Reaction mass of 2,6-Bis[(dimethylamino)methyl]-4-(1-{3-[(dimethylamino)methyl]-4-hydroxyphenyl}-1-methylethyl)phenol and 4-(1-{3,5-Bis[(dimethylamino)methyl]-4-hydroxyphenyl}-1-methylethyl)-2,6-bis[(dimethylamino)methyl]phenol to algae of was reported up to 100 mg/L.

Executive summary:

A study was performed to assess the adverse effects of Reaction mass of 2,6-Bis[(dimethylamino)methyl]-4-(1-{3-[(dimethylamino)methyl]-4-hydroxyphenyl}-1-methylethyl)phenol and 4-(1-{3,5-Bis[(dimethylamino)methyl]-4-hydroxyphenyl}-1-methylethyl)-2,6-bis[(dimethylamino)methyl]phenol (EGGE 2806-1) on the growth rate of the planktonic freshwater algal species Desmodesmus subspicatus (former name: Scenedesmus subspicatus) over several generations.

The study was conducted in accordance with Commission Regulation (EC) No 761/2009 amending Regulation No 440/2008, Method C.3 ‘Freshwater Alga and Cyanobacteria, Growth inhibition test’ (2009) which is equivalent to OECD Guideline for Testing of Chemicals No. 201 (2006).

Exponentially growing algal cells were exposed for a period of 72 hours to a range of concentrations, nominally 0.88, 1.9, 4.3, 9.4, 20.7, 45.5 and 100 mg/L of EGGE 2806-1 dissolved in dilution water. Auxiliaries used to prepare the test media were an ultrasonic bath and a magnetic stirrer.

The cell densities were measured at 24 hour intervals. Inhibition of the algal population was measured as reduction in growth rate (index r), relative to control cultures grown under identical conditions. Growth rates were also used to calculate a No Observed Effect Concentration (NOEC) and a Lowest Observed Effect Concentration (LOEC) according to Williams Multiple Sequential t-test Procedure. The following values were determined:

Results [mg/L]:

ErC 50* (0-72 h): > 100

ErC 10* (0-72 h): > 100

NOEC [r]* (tα 0.05): ≥ 100

LOEC [r]* (tα 0.05): > 100

The results are expressed in terms of nominal concentrations. Effective concentrations ranged from 100 % to 102 % of nominal values at 0 hours, and from 93 % to 102 % of nominal values at 72 hours.

Description of key information

No toxicity of Reaction mass of 2,6-Bis[(dimethylamino)methyl]-4-(1-{3-[(dimethylamino)methyl]-4-hydroxyphenyl}-1-methylethyl)phenol and 4-(1-{3,5-Bis[(dimethylamino)methyl]-4-hydroxyphenyl}-1-methylethyl)-2,6-bis[(dimethylamino)methyl]phenol  to algae of was reported up to 100 mg/L.

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

EC10 or NOEC for freshwater algae:

100 mg/L

Additional information

Effect values shall read >100 mg/L.

A study was performed to assess the adverse effects of Reaction mass of 2,6-Bis[(dimethylamino)methyl]-4-(1-{3-[(dimethylamino)methyl]-4-hydroxyphenyl}-1-methylethyl)phenol and 4-(1-{3,5-Bis[(dimethylamino)methyl]-4-hydroxyphenyl}-1-methylethyl)-2,6-bis[(dimethylamino)methyl]phenol (EGGE 2806-1) on the growth rate of the planktonic freshwater algal species Desmodesmus subspicatus (former name: Scenedesmus subspicatus) over several generations.

The study was conducted in accordance with Commission Regulation (EC) No 761/2009 amending Regulation No 440/2008, Method C.3 ‘Freshwater Alga and Cyanobacteria, Growth inhibition test’ (2009) which is equivalent to OECD Guideline for Testing of Chemicals No. 201 (2006).

Exponentially growing algal cells were exposed for a period of 72 hours to a range of concentrations, nominally 0.88, 1.9, 4.3, 9.4, 20.7, 45.5 and 100 mg/L of EGGE 2806-1 dissolved in dilution water. Auxiliaries used to prepare the test media were an ultrasonic bath and a magnetic stirrer.

The cell densities were measured at 24 hour intervals. Inhibition of the algal population was measured as reduction in growth rate (index r), relative to control cultures grown under identical conditions. Growth rates were also used to calculate a No Observed Effect Concentration (NOEC) and a Lowest Observed Effect Concentration (LOEC) according to Williams Multiple Sequential t-test Procedure. The following values were determined:

Results [mg/L]:

ErC 50* (0-72 h): > 100

ErC 10* (0-72 h): > 100

NOEC [r]* (tα 0.05): ≥ 100

LOEC [r]* (tα 0.05): > 100

The results are expressed in terms of nominal concentrations. Effective concentrations ranged from 100 % to 102 % of nominal values at 0 hours, and from 93 % to 102 % of nominal values at 72 hours.