6-methyloct-5-en-2-one

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Reference 2

Reference Type:

other: Recalculation

Title:

Unnamed

Year:

2003

Report date:

2003

Reference 3

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: German standard DIN 38412, L11

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

6-methylhept-5-en-2-one

EC Number:

203-816-7

EC Name:

6-methylhept-5-en-2-one

Cas Number:

110-93-0

IUPAC Name:

6-methylhept-5-en-2-one

Details on test material:

- Name of test material (as cited in study report): Methylheptenon
water solubility: 3.02 g/L

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

- Test organism: the waterflea Daphnia magna STRAUS was used
- Housing: 30 animals were kept together in 5 l glass beaker containing 2.1 l water at 21°C. The water was exchanged daily and a conductivity of 658 µS/cm, a Ca: Mg ratio of 5:1 and a Na:K ratio of 20:1 were measured.
- The animals showed a reproduction rate of three animals per day.
- Feeding: the animals were fed with the algae Scenedesmus subspicatus once a day.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Test temperature:

21 °C

pH:

7.56 - 7.63

Dissolved oxygen:

8.2 - 8.6 mg/l

Nominal and measured concentrations:

Nominal test concentrations of (mg/l):
58, 100, 180, 320, 580 and control

Details on test conditions:

TEST CONDITIONS
The test conditions corresponded to that in the stock culture.

TEST SYSTEM
- 4x5 daphnids were used per concentration at a total test volume of 20 ml each.
- The test substance was added to the test water without any prior treatment. Subsequently, the daphnids were added to the water.
- As control test water without test substance was used.
- The several treatments were prepared according to the standard guideline and therefore, no measurements of oxygen, pH and temperature at the beginning of the exposure (0h) were performed. After 48h of exposure these parameters were determined:

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

74 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: effective concentration due to volatilisation

Details on results:

48 h EC0 58 mg/L (nominal) based on test material
48 h EC100 320 mg/L (nominal) based on test material

Due to a moderate volatility in an experiment using 100 mg and 200 mg of 6-methylhept-5-en-2-one, but without test organisms, the evaporation over 48 hours was observed. After 48 h approximately 33 % and 35 % of the test substance were evaporated (geometric mean of of all measured TOC values between 0 h and 48 h), respectively. Therefore, the EC50(48h) can be corrected to be 74 mg/l based on 35 % evaporation.

Reported statistics and error estimates:

Using the Spearman-Kärber method a EC50 (24h) of 168 mg/l and a EC50 (48h) of 114 mg/l was calculated.