4-morpholinopropanesulphonic acid

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

ANALOGUE APPROACH JUSTIFICATION
Please refer to the attached read-across justification in section 13

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield (migrated information)

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield (migrated information)

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield (migrated information)

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Area under the curve (AUC)

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Area under the curve (AUC)

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Area under the curve (AUC)

Description of key information

The 72 h ErC₅₀ value of the read-across substance was calculated to be > 100 mg test item/L and the 72 h NOErC was determined to be 100 mg test item/L (reference 6.1.5-1).

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

EC10 or NOEC for freshwater algae:

100 mg/L

Additional information

No study data with the test item is available for short-term toxicity to aquatic algae and cyanobacteria. Therefore, a read-across to the read-across substance with a very similar chemical structure and comparable physico-chemical parameters is used to evaluate the potential for short-term toxicity to aquatic algae of the test item. 

The acute toxicity of the read-across source substance was investigated in a GLP-study according to OECD test guideline 201 using unicellular freshwater green alga Desmodesmus subspicatus CHODAT. For this purpose, exponentially growing cultures of this unicellular green algal species were exposed to a nominal concentration of 100 mg/L of the test item under defined conditions. The inhibition of growth in relation to control cultures was determined over a test period of 72 hours, and thus, over several algal generations. The purpose of the analytical part of this study was to verify the concentrations of the test item in the test medium. This study encompassed six replicates for the test item concentration of 100 mg/L and control. The EC₅₀s of potassium dichromate were tested in a current reference test. The cell concentration of each replicate was determined by measuring the absorption at 440 nm every 24 hours with a spectral photometer. With these measured values, the number of cells was calculated (linear correlation between cell concentration and absorption given). Then the growth rate µ, the area under the growth curve (AUC) and the Yield were determined. At the start and at the end of the test, the quantification of the test item in the test samples was performed using high performance liquid chromatography (HPLC) with UV. The recovery after 72 hours was 99 % of the start concentration, the measured concentration at the beginning and at the end of the test was 100 % and 99 % of the nominal concentration, respectively. Therefore, the determination of the results was based on the nominal concentrations. All validity criteria were met. The effect of the read-across source substance on freshwater green alga Desmodesmus subspicatus according to OECD TG 201 showed the following results: the 72 hour EyC₅₀ was calculated to be > 100 mg test item/L, the 72 hour EbC₅₀ was calculated to be > 100 mg test item/L and the 72 hour ErC₅₀ value was calculated to be > 100 mg test item/L. The 72 hour NOEyC was determined to be 100 mg test item/L, the 72 hour NOEbC was determined to be 100 mg test item/L and the 72 hour NOErC was determined to be 100 mg test item/L. No abnormal appearance of the algal cells was observed during the experiment.