Tetrahydro-4-methyl-2H-pyran

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:

2010-02-01 to 2010-02-03

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)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Daphnia sp., Acute Immobilization test stipulated in the "Testing Methods for New Chemical Substances" of Japan

Version / remarks:

2006

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Samples of all concentrations were taken at the start and at the end of exposure.

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: Clone A
- Source: The University of Sheffield (Address: Sheffield SlO 2UQ, United Kingdom)
- Age of parental stock (mean and range, SD): > 14 days
- Feeding during test: No.

ACCLIMATION
- Acclimation conditions (same as test or not): Yes.
- Type and amount of food: Chlorella vulgaris: 0.1 - 0.2mg organic carbon content/day_daphnia

Test type:

static

Water media type:

freshwater

Remarks:

dechlorinated tap water

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

20.2 - 20.3°C

pH:

7.7

Dissolved oxygen:

8.5 - 8.8 mg/L

Nominal and measured concentrations:

nominal: 0 (control) and 100 mg/L
measured: 0 (control) and 98 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Petri dish (diameter 8.0 cm x depth 5.0 cm), filled with approx. 250 mL test solution
- Type: Closed with glass plate
- Aeration: No
- Renewal rate of test solution (frequency/flow rate): 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: tap water
- Total organic carbon: 0.1 mg/L
- Particulate matter: < 1 mg/L
- Metals: Yes, all concentration < 0.0005 mg/L
- Chlorine: 14 mg/L
- Alkalinity: 35 mg/L
- Ca/Mg ratio: 3.46
- Culture medium different from test medium: No.

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16-hour light/8-hour dark
- Light intensity: Not stated

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Immobility of daphnids after 24 and 48 hours.

RANGE-FINDING STUDY
- Test concentrations: 100 mg/L
- Results used to determine the conditions for the definitive study: Yes.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 98 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Mortality of control: No.

Results with reference substance (positive control):

The EC50-value of the daphnia acute toxicity test with potassium chromate was within the stipulated range (mean ± 2S.D.: 0.13 - 0.36 mg/L) to background data in the laboratory [mean ± S.D.: 0.24 ± 0.056 mg/L (n=69)].

Table 1: Immobility of daphnids

Nominal concentration(mg/L)	Immobility %
		24 hours		48 hours
	Replicates		Test level	Replicates	Test level
Control	A	0	0	0	0
	B	0	0	0	0
	C	0	0	0	0
	D	0	0	0	0
100	A	0	0	0	0
	B	0	0	0	0
	C	0	0	0	0
	D	0	0	0	0

Table 2: Conditions of the test

Nominal concentration(mg/L)	Dissolvedoxygen concentration(mg/L)				pH		Temperature(°C)
	Start	End		Start		End	Start	End
Control	8.8		8.5		7.7	7.7	20.3	20.2
100	8.8		8.5		7.7	7.7	20.3	20.2

Validity criteria fulfilled:

yes

Conclusions:

As no immobility was observed in the highest test concentration, the 48-hour EC50 was determined as > 100 mg/L based on nominal concentration.

Executive summary:

The toxicity of the test item Tetrahydro-4-methyl-2H-pyran was examined in a acute daphnia test according to OECD 202 and under GLP conditions. Individuals of D. magna were exposed to 0 (control) and 100 mg/L of the test substance, equivalent to 98 mg/L mean measured concentration, for 48 hours. Concentrations were analytically verified via GC-FID. As no immobility was observed in the highest test concentration, the 48-hour EC50 was determined as > 100 mg/L based on nominal concentration.

Description of key information

EC50 (48-h) > 100 mg/L based on nominal concentration

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

The toxicity of the test item Tetrahydro-4-methyl-2H-pyran was examined in a acute daphnia test according to OECD 202 and under GLP conditions. Individuals of D. magna were exposed to 0 (control) and 100 mg/L of the test substance, equivalent to 98 mg/L mean measured concentration, for 48 hours. Concentrations were analytically verified via GC-FID. As no immobility was observed in the highest test concentration, the 48-hour EC50 was determined as > 100 mg/L based on nominal concentration.