6-methyloct-5-en-2-one

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

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, most sensitive study available on this endpoint, but no GLP and no analytics were performed

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Reference 3

Reference Type:

other: calculation

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: German standard DIN 38 412, Part 15

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
- Lot/batch No.: 88/602
- Analytical purity: 98.2 %
- Physical state: liquid
water solubility: slightly soluble.

Sampling and analysis

Analytical monitoring:

no

Test solutions

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test substance was added to the test water without any prior treatment.

Test organisms

Test organisms (species):

Leuciscus idus

Details on test organisms:

TEST ORGANISM
- Common name: Golden Orfe
- Length at study initiation (length definition, mean, range and SD): 6.0 cm (range: 5.5-7.1)
- Weight at study initiation (mean and range, SD): 1.8 g (range: 1.2-2.8)
- Feeding during test: 1 day before and during exposure


ACCLIMATION
- Acclimation period: 3 days

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Hardness:

2.5 mmol/l

Test temperature:

21+/-1°C

pH:

7.5 - 7.9

Dissolved oxygen:

7.5 - 8.7 mg/l

Nominal and measured concentrations:

Nominal test concentrations (mg/l):
46.6,
100,
215,
464,
1000,
control

Details on test conditions:

TEST SYSTEM
- Test vessel: All-glass aquarium non-sealed (30 x 22 x 24 cm)
- Fill volume: 10 l
- Aeration: slight
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 1.8 g fish/l test water


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water chemistry: reconstituted freshwater was prepared from demineralized tap water that was resalted by the addition of 294.0 mg/l CaCl2*2H2O, 123.3 mg/l MgSO4*7H2O, 63.0 mg/l NaHCO3 and 5.5 mg/l KCl.


OTHER TEST CONDITIONS
- Photoperiod: 16:8 h day-night regime


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality and symptoms of intoxication

Results and discussion

Effect concentrations

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

50 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: effective concentration due to volatility

Details on results:

96 h NOEC 46.4 mg/L (nominal) based on test material
96 h LC0 46.4 mg/L (nominal) based on test material
96 h LC100 100 mg/L (nominal) based on test material

In the control and up to nominal 46.4 mg test item/L, no fish died within 96 h of exposure and displayed no symptoms of intoxication. After 4 h, all fish died at nominal 100, 215, 464 and 1000 mg/l 6-methylhept-5-en-2-one. Thus, using the geometric mean of the LC0 of 46 mg/l and the LC100 of 100 mg/l a LC50 of 68.1 mg/l (geometric mean) could be calculated.
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 96 hours was observed. After 96 h approximately 23 % and 26 % of the test substance was evaporated (geometric mean of all measured TOC values between 0 h and 96 h), respectively. Therefore, the LC50(96h) can be corrected to be approximately 50 based on 26% evaporation.

Results with reference substance (positive control):

The 48 h EC50 of the positive control (chloroacetamide) was 32 mg/l.