[No public or meaningful name is available]

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:

2019-04-10 to 2019-04-12

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

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Remarks:

HPLC-DAD method

Details on sampling:

The concentrations of the test item were analytically verified via HPLC-DAD in fresh media at the start of the exposure and at renewal (0 and 24 h) and in old media (24 and 48 h).

Vehicle:

no

Details on test solutions:

A stock solution (100 mg/L of the test item were weighed out) was freshly prepared with dilution water prior to the start of the exposure (at 0 hours) and prior to the renewal of the test solutions (at 24 hours). The stock solution was mixed thoroughly by manual agitation until the test item was completely dissolved. 5 test item concentrations in a geometric series with a separation factor of 1.78, prepared by dilution of the stock solution 100 mg/L with dilution water, were tested as follows: 9.96 - 17.7 - 31.6 - 56.2 - 100 mg/L

Test organisms (species):

Daphnia magna

Details on test organisms:

Origin: Institut für Wasser-, Boden- und Lufthygiene (WaBoLu), 14195 Berlin, Germany
Breeder: Noack Laboratorien GmbH, Käthe-Paulus-Str. 1, 31157 Sarstedt, Germany
Culture medium: Elendt M4, according to OECD 202, Annex 3 (2004), is used.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

285-298 mg CaCO3/L

Test temperature:

20.2-20.7°C

pH:

24h: 7.66-7.76; 48h: 7.40-7.80

Dissolved oxygen:

24h: 8.12-8.66; 48h: 6.89-7.69

Conductivity:

639-681 µS/cm

Nominal and measured concentrations:

Nominal concentrations: 9.96 - 17.7 - 31.6 - 56.2 - 100 mg/L;
Measured concentrations (fresh media ): 10.5 -18.3 - 33.8 - 58.8 -106 mg/L;
Measured concentrations (old media ): 9.62 - 16.75 - 30.65 - 54.9 - 98.15 mg/L.

Reference substance (positive control):

yes

Remarks:

The reference substance Potassium dichromate was determined after 24 hours from 2019-03-06 to 2019-03-07.

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

25.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

59.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

See Table 1

Results with reference substance (positive control):

The 24h-EC50 value was 2.17 mg/L (valid range: 0.6-2.4 mg/L, acc. to AQS P 9/2 (02/2000).

Table 1: Immobilization rates after 24 and 48 hours of Exposure in the definitive test.

Nominal concentration [mg/L]	Immobilization [%]
	24 hours					48 hours
	Replicates					Replicates
	1	2	3	4	Mean	1	2	3	4	mean
100	80	80	100	80	85	100	100	100	100	100
56.2	40	0	0	80	30	40	80	80	100	75
31.6	0	0	0	0	0	40	80	60	60	60
17.7	21	0	0	0	5	20	20	80	60	45
9.96	0	0	0	0	0	0	0	0	0	0
Control	0	0	0	0	0	0	0	0	0	0

Validity criteria fulfilled:

yes

Conclusions:

The short term toxicity to Daphnia magna was determined and the 48h-EC50 value was 25.2 mg/L.

Executive summary:

The acute immobilization effect of the test item to Daphnia magna (STRAUS) was performed according to OECD guideline 202 (2004) and GLP. The study was conducted in a closed system without headspace under semi-static conditions over a period of 48 hours. Based on the results of a preliminary study, five concentrations within a range of 9.96-100 mg/L ina gerometric series with a separation factor of 1.78 were tested. Twenty daphnids (divided into 4 replicates with 5 daphnids each) were exposed to each concentration level and the control (test medium without test item). The concentrations of the test item were analytically verified via HPLC-DAD in fresh media at the start of the exposure and at renewal (0 and 24 h) and in old media (24 and 48 h). The measured concentrations were within the range of ±20% of the nominal values, the effect concentrations were given on the basis of the nominal concentrations. The 48h-EC50 value was determined to be 25.2 mg/L.

Description of key information

An acute immobilization effect of the test item to Daphnia magna (STRAUS) was performed according to OECD guideline 202 (2004) and GLP. The study was conducted in a closed system without headspace under semi-static conditions over a period of 48 hours. Based on the results of a preliminary study, five concentrations within a range of 9.96-100 mg/L ina gerometric series with a separation factor of 1.78 were tested. Twenty daphnids (divided into 4 replicates with 5 daphnids each) were exposed to each concentration level and the control (test medium without test item). The concentrations of the test item were analytically verified via HPLC-DAD in fresh media at the start of the exposure and at renewal (0 and 24 h) and in old media (24 and 48 h). The measured concentrations were within the range of ±20% of the nominal values, the effect concentrations were given on the basis of the nominal concentrations. The 48h-EC50 value was determined to be 25.2 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

25.2 mg/L