Sodium 1-amino-9,10-dihydro-4-[5-[(2-hydroxyethyl)sulphamoyl]-3,4-xylidino]-9,10-dioxoanthracene-2-sulphonate

Toxicity to aquatic plants other than algae

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic plants other than algae

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 221 (Lemna sp. Growth Inhibition Test)

Deviations:

yes

Remarks:

No major (pH of the control increased by more than 1.5 units during the test. The test is still valid, as it was shown that validity criteria are met).

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Name: FAT 20033/L
Batch number: AT-PD13-359A1
EAS Test item code: 2014-000179
Appearance / colour: solid / dark blue
Date of analysis: 07 Jan 2014
Expiry date: 07 Jan 2019
Storage conditions: ambient (+5 to +30 °C), dark, dry

Analytical monitoring:

yes

Details on sampling:

After sampling, the test medium samples (0.5 mL) were mixed with 0.5 mL methanol and stored deep-frozen (below -18 °C) until analysis.

Vehicle:

no

Details on test solutions:

The necessary amount of test item for preparing the stock solution S1 was weighed and transferred to a volumetric flask. Test medium was added up to the bench mark and the solution was homogenised by shaking. Lower concentrations of the test item were prepared by dilution of the stock solution.

Test organisms (species):

Lemna gibba

Details on test organisms:

The test organism was the aquatic plant duckweed, Lemna gibba G3 (Alismatales: Araceae). The plants used in this study were taken as aseptic clones from the cultivation of the testing facility. They were primarily cultured by Dr. Janet Slovin, Horticulture Crops Quality Laboratory, U.S. Department of Agriculture. BARC-West, Bldg. 050 HH-4, Beltsville, MD 20705, U.S.A. The plants were cultured in appropriate glass beakers under continuous illumination with OSRAM light tubes (L30/32-930 and L30/W72-965), at 6500 - 7000 lux. The temperature was 24 ± 2 °C. Before the test was started, plants were cultured under the same illumination and temperature conditions as those to be used for the toxicity test. Young, light-green plants of similar size and comprising 2 - 5 fronds were transferred onto fresh medium and cultured for 3 weeks prior to testing, with two further transfers onto fresh medium before initiating the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

7 d

Hardness:

none

Test temperature:

23.1 – 24.7 °C

pH:

7.45 – 7.61

Nominal and measured concentrations:

0, 0.298, 0.954, 3.05, 9.77, 31.3 and 100 mg/L

Details on test conditions:

Light intensity (mean): ~ 6800 lux OSRAM light tubes (L 30 W77 and L 30 W25)
Exposure to light: continuously
Test vessels: 250 mL glass beakers filled with 150 mL
Number of fronds: 12 per test vessel

Reference substance (positive control):

no

Duration:

7 d

Dose descriptor:

EC10

Effect conc.:

1.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of frond number

Remarks on result:

other: 0.727-2.02

Duration:

7 d

Dose descriptor:

EC20

Effect conc.:

4.17 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of frond number

Remarks on result:

other: 2.79-5.72

Duration:

7 d

Dose descriptor:

EC50

Effect conc.:

24.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of frond number

Remarks on result:

other: 19.2 – 30.5

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

0.954 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of frond number

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

3.05 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of frond number

Duration:

7 d

Dose descriptor:

EC10

Effect conc.:

6.78 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of frond number

Remarks on result:

other: 3.80-10.2

Duration:

7 d

Dose descriptor:

EC20

Effect conc.:

20.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of frond number

Remarks on result:

other: 14.5-28.3

Duration:

7 d

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of frond number

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

3.05 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of frond number

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

9.77 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of frond number

Duration:

7 d

Dose descriptor:

EC10

Effect conc.:

2.51 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of dry weight

Remarks on result:

other: 1.55-3.59

Duration:

7 d

Dose descriptor:

EC20

Effect conc.:

5.35 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of dry weight

Remarks on result:

other: 3.76-7.02

Duration:

7 d

Dose descriptor:

EC50

Effect conc.:

19.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of dry weight

Remarks on result:

other: 15.6 – 24.4

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

3.05 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of dry weight

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

9.77 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield of dry weight

Duration:

7 d

Dose descriptor:

EC10

Effect conc.:

6.26 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of dry weight

Remarks on result:

other: 3.51-9.33

Duration:

7 d

Dose descriptor:

EC20

Effect conc.:

16.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of dry weight

Remarks on result:

other: 11.2-21.5

Duration:

7 d

Dose descriptor:

EC50

Effect conc.:

68.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of dry weight

Remarks on result:

other: 53.7 – 91.2

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

3.05 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of dry weight

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

9.77 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate of dry weight

Reported statistics and error estimates:

The statistical evaluation for day 7 was performed for yield of frond numbers, growth rate of frond numbers, growth rate of dry weight and yield of dry weight. A test for normality of the data was performed by calculating the Shapiro-Wilk’s statistic, a test for homogeneity of the data was performed according to Levene. The NOEC and LOEC were determined by using a multiple comparison method (Dunnett`s t-test, Jonckheere-Terpstra and Bonferroni-Holms corrected Welch-test). The EC10, EC20 and EC50 values for yield of frond number, yield of dry weight and growth rate of dry weight were determined by probit analysis following logistic and Gompertz procedure. The EC10 and EC20 values for growth rate of frond numbers were determined by probit analysis following Gompertz procedure The calculation of EC50 values for growth rate of frond numbers was not indicated since inhibition was below 50 %. The evaluation of data was performed by SAS® (2002-2010).

Summary of results:

	Test item [mg/L] nominal
Endpoint	EC10	EC20	EC50	NOEC	LOEC
Yield of frond numbers	1.3	4.17	24.2	0.954	3.05
Growth rate of frond numbers	6.78	20.8	>100	3.05	9.77
Yield of dry weight	2.51	5.35	19.4	3.05	9.77
Growth rate of dry weight	6.26	16.2	68.5	3.05	9.77

Validity criteria fulfilled:

yes

Conclusions:

The nominal EC10-value for growth rate of frond numbers was determined to be 6.78 mg/L, while the nominal EC50-value for growth rate of frond numbers was determined to be >100 mg/L.

Executive summary:

The aim of the study was to assess the effect of the test item on the growth of Lemna gibba according to OECD Guideline 221 and derive EC10, 20, 50 and NOEC/LOEC values. The nominal concentration used are as follows; 0, 0.298, 0.954, 3.05, 9.77, 31.3 and 100 mg/L. The initial mean measured concentration of FAT 20033/L in the test item solutions was 104 % of nominal. The overall mean concentration of fresh and aged samples was 101 % of nominal. Toxicological endpoints were evaluated using nominal concentrations of the test item. Significant inhibitory effects were determined for yield of frond numbers at 3.05, 9.77, 31.3 and 100 mg/L (nominal). Significant inhibitory effects were determined for yield of dry weight and for growth rate of dry weight and frond numbers at 9.77, 31.3 and 100 mg/L. The overall LOEC was therefore determined to be 3.05 mg/L, the corresponding NOEC at 0.954 mg/L. The nominal EC10-value for yield of frond numbers was determined to be 1.30 mg/L, the nominal EC10-value for yield of dry weight was determined to be 2.51 mg/L. The nominal EC10-value for growth rate of dry weight was determined to be 6.26 mg/L. The nominal EC10-value for growth rate of frond numbers was determined to be 6.78 mg/L. The nominal EC20-value for yield of frond numbers was determined to be 4.17 mg/L, the nominal EC20-value for yield of dry weight was determined to be 5.35 mg/L. The nominal EC20-value for growth rate of dry weight was determined to be 16.2 mg/L. The nominal EC20-value for growth rate of frond numbers was determined to be 20.8 mg/L. The nominal EC50-value for yield of frond numbers was determined to be 24.2 mg/L, the nominal EC50-value for yield of dry weight was determined to be 19.4 mg/L. The nominal EC50-value for growth rate of dry weight was determined to be 68.5 mg/L. The nominal EC50-value for growth rate of frond numbers was determined to be >100 mg/L.

Description of key information

The nominal EC10-value for growth rate of frond numbers was determined to be 6.26 mg/L, while the nominal EC50 -value for growth rate of frond numbers was determined to be 68.5 mg/L.

Key value for chemical safety assessment

EC50 for freshwater plants:

68.5 mg/L

EC10 or NOEC for freshwater plants:

6.26 mg/L

Additional information

The effect of Acid Blue 277 on the growth of Lemna gibba was assessed in a study conducted according to OECD Guideline 221. The nominal concentration used are as follows; 0, 0.298, 0.954, 3.05, 9.77, 31.3 and 100 mg/L. The nominal EC10-value for yield of frond numbers was determined to be 1.30 mg/L, the nominal EC10-value for yield of dry weight was determined to be 2.51 mg/L. The nominal EC10-value for growth rate of dry weight was determined to be 6.26 mg/L. The nominal EC10-value for growth rate of frond numbers was determined to be 6.78 mg/L. The nominal EC50-value for yield of frond numbers was determined to be 24.2 mg/L, the nominal EC50-value for yield of dry weight was determined to be 19.4 mg/L. The nominal EC50-value for growth rate of dry weight was determined to be 68.5 mg/L. The nominal EC50-value for growth rate of frond numbers was determined to be >100 mg/L. The test is valid as the doubling time of control frond numbers was calculated to be 37.9 h, corresponding to 1.581 days at day 7. This is less than the maximum allowable doubling time set in OECD guideline 221 (60 h, 2.5 days).