Calcium 3-hydroxy-4-[(1-sulphonato-2-naphthyl)azo]-2-naphthoate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP guideline study available as unpublished report, minor restrictions in design and reporting but otherwise adequate for assessment.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Qualifier:

according to guideline

Guideline:

ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))

GLP compliance:

not specified

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
The test substance was stirred in M4 medium for about 20 hours at 20 ± 2 °C. Undissolved test substance was removed by centrifugation (approximately 20 min at about 17700 G). The nominal concentration of the eluate was 100 mg/L. This eluate was diluted with M4 medium to obtain the required test concentrations.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain: Daphnia magna STRAUS
- Source: The clone of Daphnia magna STRAUS used was supplied by Institut National de Recherche Chimique Appliquée, France, in 1978. The daphnids are cultured under standard conditions in the laboratory of ecotoxicology, BASF AG, "Ludwigshafen".
- Age at study initiation (mean and range, SD): 2-24 h
- Feeding during test: No

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

2.42 mmol/L

Test temperature:

20.3-20.5 °C

pH:

8.0-8.2

Dissolved oxygen:

8.5-8.7

Nominal and measured concentrations:

Nominal concentrations: Control, 12.5, 25, 50, 100 mg/L (based on range-finding test)

Details on test conditions:

TEST SYSTEM
- Test vessel: Test tubes (glass) with fIat bottom (nominal volume 20 mL); fill volume: 10 mL
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: synthetic medium M4
- This synthetic medium has the following properties:
- Total hardness 2.20 - 3.20 mmol/L
- Alkalinity up to pH 4.3: 0.80 - 1.00 mmol/L
- Molar ratio Ca/Mg: about 4:1
- pH value: 7.5-8.5
- Conductivity : 550 - 650 µS/cm

OTHER TEST CONDITIONS
- Photoperiod: Artificial Iight, OSRAM L58 W31 warm white; day/night-rhythm = 16 / 8 hours
- Light intensity: About 2 - 7 µE/(m2xS) in the range of 400 - 700 nm

EFFECT PARAMETERS MEASURED:
Swimming ability of the test animals: Visually after 0, 24 and 48 h

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

After 48 hours, at the highest concentration tested, a single test organism was found to be immobile.

The test was performed with an aqueous extract (eluate) of the test substance. 
The test substance showed no inhibitory effect in the range of its water solubility.

Validity criteria fulfilled:

yes

Conclusions:

The test item is with high probability not acutely harmful to aquatic invertebrates. No toxic effects occur within the range of solubility.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

For the determination of the actual test item concentration, duplicate samples were taken from each treatment before the start and at the end of the test.
For the 48-hour stability samples additional flasks with adequate volumes of the freshly prepared test medium and the control were incubated during the test period imder the same conditions as in the actual test (but without daphnids). Sampling from the test beakers with daphnids was not possible because the test medium volume per beaker (50 mL) was too small for the analytical requirements (500 mL per sample).
All samples were stored deep-frozen (at about -20 °C) immediately after sampling. Based on preexperiments for investigation of the storage stability (without GLP), the analyzed main component of the test item was found to be sufficiently stable in the test water under these storage conditions.
The concenfration of the main component of the test item was analytically measured in the duplicate test medium samples of the single test concenfration taken at the start and the end of the test. From the control, only one of the duplicate samples was analyzed from each of the sampling times.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Due to the limited water solubility of the product, containing sparingly soluble components, a water accommodated fraction (WAF) was prepared according to OECD guidence documet No. 23. A dispersion of 100 mg/L was prepared by dispersing 250.4 mg of the test item into 2500 ml of test water. The dispersion was stirred in the dark for 3 hours. After the stirring period of 3 hours, the dispersion was filtered through a membrane filter

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: clone 5
- Source: Originally supplied by the University of Sheffield, UK in 1992. Since that time, the clone has been bred in the laboratories of RCC.
- Age at study initiation (mean and range, SD): 6 - 24 hours
- Feeding during test; none
- Housing conditions: same as test

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

2.5 mmol/L

Test temperature:

20 °C

pH:

7.8

Dissolved oxygen:

8.0 - 8.6 mg/L

Nominal and measured concentrations:

Nominal test concentrations: control, 100 mg/L
Mean measured concentrations: n.a., 0.0086 mg/L
n.a. = not applicable

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, nominal volume, fill volume: glass beakers, 100 ml, 50 ml
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Biomass loading rate: 0.5 daphnia/ ml

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted test water aerated prior to the test strat until oxygen saturation was reached
- Alkalinity: 0.8 mmol/L
- Ca/Mg ratio: 4:1
- Culture medium different from test medium: no
- Intervals of water quality measurement: Temperature, pH, oxygen content after 0 and 48 hours

OTHER TEST CONDITIONS
- Photoperiod: 16 hour light : 8 hour darkness (30 min transition period)
- Light intensity: 490 to 640 lux

EFFECT PARAMETERS MEASURED: immobility after 24, 48 hours

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: none
- Mortality of control: none
- Apperance of the test medium: no remarkable observations, clear test medium

Results with reference substance (positive control):

EC50 (48 h) = 0.73 mg/L (control test in Dec 2006)

Validity criteria fulfilled:

yes

Conclusions:

calcium 4-[(5-chloro-4-methyl-2-sulfonatophenyl)diazenyl]-3-hydroxy-2-naphthoate is with high probability not acutely harmful to aquatic invertebrates. No toxic effects occur within the range of solubility.

Description of key information

The test item is with high probability not acutely harmful to aquatic invertebrates. No toxic effects occur within the range of solubility.

Additional information

The toxicity of the test substance to aquatic invertebrates was examined in a non-GLP study according to OECD guideline 202 (BASF 2000). In this study, Daphnia magna (4 replicates of 5 animals per concentration) were exposed to nominal concentrations of 12.5, 25, 50, 100 mg/L and a blank control for 48 hours. The test solutions were saturated for 20 h and undissolved test material was removed by centrifugation. The loading rate of the eluate was 100 mg/L and the test concentrations were produced by diluting the eluate. No analytical verification of nominal test concentrations was performed. At the start of the test and after 24 and 48 hours each test vessel was visually checked for immobilised daphnids. After 48 hours, at the highest concentration tested, a single test organism was found to be immobile. No additional adverse effects or abnormal behaviour are reported in any of the test treatments. Based on these findings, the 48-h EC50 value is determined at >100 mg/L (nominal) or > maximum solubility in test medium.

The results are supported by a toxicity study to Daphnia magnaa ccording OECD 203 and GLP with the read-across substance (CAS 7023-61-2; RCC Ltd. 2007). Due to the low solubility of the test substance a water accommodated fraction has been used. No effects have been observed after 48 h with the loading rate of 100 mg/L. Therefore, the EC50 after 48 h was determined to be > 100 mg/L (nominal) and the NOEC was determined to be >= 100 mg/L.

Hence, the test item is with high probability not acutely harmful to aquatic invertebrates. No toxic effects occur within the range of solubility.