Laccase

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:

From January 25, 1996 to April 15, 1996

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:

1984

Deviations:

no

GLP compliance:

yes

Remarks:

Certificate included in report

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100 mg dry material/L
- Sampling method: Duplicate samples from the control and the test solutions of SP807 were taken at the beginning and at the end of the test. Samples of ca. 5 mL were taken in polyethylene bottles.
- Sample storage conditions before analysis: frozen

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia
- Strain: Daphnia magna
- Source: TNO
- Age at study initiation (mean and range, SD): <24h
- Feeding during test: no

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

Ca. 205 mg CaCO3/L

pH:

7.5-8.0

Dissolved oxygen:

6.9-9.2 mg/L

Nominal and measured concentrations:

nominal: 100 mg TOS/L
measured: 74 mg TOS/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 150 mL glass beaker
- Material, size, fill volume: glass, 150 mL, 100 mL
- Aeration: no
- 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 media (DSWL) prepared from ground water
- Total organic carbon: 1.7 mg/L
- Chlorine: 2.72 mg/L



OTHER TEST CONDITIONS
- Photoperiod: 16h light, 8h dark


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Mobility and immobility, condition of mobile animals (svimming behaviour, colour or any other visually observable morphological or behavioural criterion). Observations were made after 24h and at the end of the test (48h).

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

>= 100 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

>= 74 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: dry matter

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 74 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: dry matter

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 2.68 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: active enzyme protein (aep)

Basis for effect:

mobility

Conclusions:

No immobilisation was observed following the exposure of Daphnia magna to the test substance at a concentration of 74 mg dry material/L. Due to the low toxicity of the test material, the 48-hour EC50 value of the substance was unable to be calculated. Therefore the following values were assumed:
The 48-hour EC50 value for the test substance with Daphnia magna was determined to be >74 mg dry material/L corresponding to 2.68 > mg active enzyme protein (aep)/L.
The no-observed effect concentration (NOEC) was 74 mg dry material/L corresponding to 2.68 mg aep/L.

Executive summary:

The acute toxicity of the test substance to Daphnia magna was assessed under static exposure conditions.The study was conducted according to OECD and EC guidelines, and in compliance with GLP.

A group of 20 Daphnia were exposed to the test substance for 48 hours at a nominal concentration of 100 mg dry material/L. Mean measured concentration was 74 mg dry material/L.

Verification of test concentrations was performed based on enzyme activity. The amount of measured enzyme (LACU/g) was then converted to mg dry matter/L in order to calculate the achieved measured concentrations. Measured concentrations ranged were 67 % of nominal at 0 hours and between 79 -84% at 48 hours. The average percentage present during the test was 74%

The numbers of immobilised daphnids were recorded for each test and control group after 24 and 48 hours. All results are expressed in terms of mean measured concentration.

No immobilisation in either the control or the test group was noted throughout the exposure period, and therefore the following values were estimated:

48-hour EC50: >100 mg dry matter/L corresponding to > 2.68 mg active enzyme protein (aep)/L

NOEC: 100 mg dry matter/L corresponding to 2.68 mg aep/L

Description of key information

No immobilisation was observed following the exposure of Daphnia magna to the test substance at a concentration of 74 mg dry material/L. Due to the low toxicity of the test material, the 48-hour EC50 value of the substance was unable to be calculated. Therefore the following values were assumed: The 48-hour EC50 value for the test substance with Daphnia magna was determined to be >74 mg dry material/L corresponding to 2.68 > mg aep/L. The no-observed effect concentration (NOEC) was 74 mg dry material/L corresponding to 2.68 mg aep/L.

Additional information

The acute toxicity of the test substance to Daphnia magna was assessed under static exposure conditions.The study was conducted according to OECD and EC guidelines, and in compliance with GLP.

A group of 20 Daphnia were exposed to the test substance for 48 hours at a nominal concentration of 100 mg dry material/l. Mean measured concentration was 74 mg dry material/L.

Verification of test concentrations was performed based on enzyme activity. The amount of measured enzyme (LACU/g) was then converted to mg dry matter/L in order to calculate the achieved measured concentrations. Measured concentrations ranged were 67 % of nominal at 0 hours and between 79 -84% at 48 hours. The average percentage present during the test was 74%

The numbers of immobilised daphnids were recorded for each test and control group after 24 and 48 hours. All results are expressed in terms of mean measured concentration.

No immobilisation in either the control or the test group was noted throughout the exposure period, and therefore the following values were estimated:

48-hour EC50: >100 mg dry matter/L corresponding to > 2.68 mg aep/L

NOEC: 100 mg dry matter/L corresponding to 2.68 mg aep/L