4-hydroxybenzaldehyde

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-10-05 to 2017-12-13

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)

Version / remarks:

2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

Council Regulation (EC) No. 440/2008 laying down test methods pursuant to Regulation (EC) No. 1907/2006 of the European Parliament and the council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

For the determination of the test item concentration, two replicates of each sample were deep-frozen (< -20 °C) directly after preparation and after 48h and stored in a freezer until analysis. Analysis of the test item concentration at the beginning and at the end of the exposure period was analyzed using HPLC method with UV detection.

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
A preparation with a test item concentration of 100 mg/L was freshly prepared. For that purpose, the test item will be weighed in a calibrated flask and vehicle was added. The preparation was stirred with a magnetic stirrer for 1 hour. This solution was used for the preparation of the different test item concentrations. The pH value was not adjusted.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISMst
- Common name: water flea
- Strain/clone: Straus
- Age at study initiation: 24 hours old
- Source: IBACON GmbH (Roßdorf, Germany)
- Feeding during test: no

ACCLIMATION
- Acclimation period: none

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

236 mg CaCO3/L

Test temperature:

20.4 - 20.9 °C

pH:

7.12 - 7.84

Dissolved oxygen:

8.69 - 8.87 mg/L

Conductivity:

666 µS/cm

Nominal and measured concentrations:

Nominal concentrations: 10.0, 17.8, 31.6, 56.3 and 100.0 mg/L
Measured concentrations: > 80 % of nominal concentrations

Details on test conditions:

TEST SYSTEM
- Test vessel: glass test tubes
- Type: open
- Material, size, fill volume: glass, 20 mL, 20 mL
- Volume of solution: 20 mL
- Aeration: no
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Biomass loading rate: 4 mL medium/daphnid

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water (ELENDT M4 medium)
- Conductivity: 666 µS/cm
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hour light and 8 hour dark regime
- Light intensity: 575 Lux and 629 Lux

EFFECT PARAMETERS MEASURED: 24 and 48 hours after start of exposure, the daphnids were visually examined for their ability to swim. Those daphnids that did not make any swimming movements within 15 seconds after the test vessel had been gently agitated, were regarded as immobilized.

RANGE-FINDING STUDY
- Test concentrations: 0, 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

74.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % Confidence Interval: 57.5 - 110.9 mg/L

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

41.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % Confidence Interval: 34.7 - 48.7 mg/L

Details on results:

Under the conditions of the present study, the test item showed a 48h EC50 of 41.1 mg/L.

Results with reference substance (positive control):

Potassium dichromate:
24h EC50 1.13 mg/L (0.98 – 1.34 mg/L)
48h EC50 0.74 mg/L (0.66 – 0.82 mg/L)

The reference item (Potassium dichromate) showed a 24h EC50 value of 1.13 mg/L which is within the range of the published data of 0.6 to 1.7 mg/L (Council Regulation (EC) No. 440/2008) and 0.6 to 2.1 mg/L (OECD Guideline No. 202).

Table1: Concentration dependent immobilization in a static pre-test (non-GLP)

Nominal concentration [mg/L]	Number of daphnids immobilized / exposed
	24 hours	48 hours
Control	0/20	0/20
1	0/20	0/20
10	0/20	0/20
100	11/20	20/20

 

Table 2: Biological Results

Nominal Test Item Concentration [mg/L]	Number of daphnids immobilized / exposed		% of daphnids immobilized
	24 hours	48 hours	24 hours	48 hours
0.0	0/20	0/20	0%	0%
10.0	0/20	0/20	0%	0%
17.8	0/20	0/20	0%	0%
31.6	3/20	7/20	15%	35%
56.3	10/20	14/20	50%	70%
100.0	11/20	20/20	55%	100%

 

Table 3: EC₅₀-Values

Test Duration	EC50	95% Confidence Interval
24h	74.1 mg/L	57.5-110.9 mg/L
48h	41.1 mg/L	34.7-48.7 mg/L

 

Table 4: The results of the analyses of all samples received are summarized in the following table. Each value represents the mean concentration of three measurements.

Nominal test item concentration [mg/L]	Analytical results
	0-h		48-h
	[mg/L]	Recovery from nom. [%]	[mg/L]	Recovery from nom. [%]	Recovery from 0-h cone. [%]
0.0	<LOD	-	<LOD	-	-
10.0	10.012	100.1	9.417	94.2	94.1
17.8	17.733	99.6	16.845	94.6	95.0
31.6	31.271	99.0	29.385	93.0	94.0
56.3	55.719	99.0	54.403	96.6	97.6
100.0	99.541	99.5	98.303	98.3	98.8

LOD = Limit of detection (0.002 mg/L)

 

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present study, the test item showed a 48h EC50 of 41.1 mg/L.

Executive summary:

The influence of the test item on Daphnia magna was assessed in a 48-h Acute Immobilisation Test according to OECD TG 202. For this purpose, young daphnids, aged less than 24 hours old at the start of the study, were exposed for a period of 48 hours to five concentrations of nominal 0.0, 10.0, 17.8, 31.6, 56.3, and 100.0 mg/L of the test item in an open static system. 20 daphnids, divided into four replicates, each of five animals were used per test item group and the control group. Immobilization was recorded at 24 and 48 hours and compared with control values. The results were analyzed to calculate the EC50 at 24h and 48h. Samples of the test and control medium were taken directly after preparation and at the end of exposure (48h) and stored at < -20°C until further analysis of the test item concentration via HPLC with UV detection. The purpose of the analytical part of this study was to verify the concentrations of the test item in the test medium. The accuracy and reliability of the test method is demonstrated periodically as recommended by guidelines. In the control group, no daphnids were immobilized and the dissolved oxygen concentration at the end of the exposure period was > 3 mg/L. Thus, all validity criteria were fulfilled. No effect on the mobility of the daphnia was observed at the two lowest concentrations of nominal 10.0 and 17.8 mg/L. A concentration dependent immobilization was observed between 31.6 and 100.0 mg/L. Under the conditions of the present study, the test item showed a 48-h EC₅₀ of 41.1 mg/L.

 

Description of key information

Under the conditions of the present study, the test item showed a 48-h EC₅₀ of 41.1 mg/L (reference 6.1.3-1).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

41.1 mg/L

Additional information

The influence of the test item on Daphnia magna was assessed in a 48-h Acute Immobilisation Test according to OECD TG 202. For this purpose, young daphnids, aged less than 24 hours old at the start of the study, were exposed for a period of 48 hours to five concentrations of nominal 0.0, 10.0, 17.8, 31.6, 56.3, and 100.0 mg/L of the test item in an open static system. 20 daphnids, divided into four replicates, each of five animals were used per test item group and the control group. Immobilization was recorded at 24 and 48 hours and compared with control values. The results were analyzed to calculate the EC50 at 24h and 48h. Samples of the test and control medium were taken directly after preparation and at the end of exposure (48h) and stored at < -20°C until further analysis of the test item concentration via HPLC with UV detection. The purpose of the analytical part of this study was to verify the concentrations of the test item in the test medium. The accuracy and reliability of the test method is demonstrated periodically as recommended by guidelines. In the control group, no daphnids were immobilized and the dissolved oxygen concentration at the end of the exposure period was > 3 mg/L. Thus, all validity criteria were fulfilled. No effect on the mobility of the daphnia was observed at the two lowest concentrations of nominal 10.0 and 17.8 mg/L. A concentration dependent immobilization was observed between 31.6 and 100.0 mg/L. Under the conditions of the present study, the test item showed a 48-h EC₅₀ of 41.1 mg/L (reference 6.1.3-1).