1,3-Oxathiolane-2-carboxylic acid, 5-hydroxy-, (1R,2S,5R)-5-methyl-2-(1-methylethyl)cyclohexyl ester, (2R,5R)-

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15.11.2004 to 02.12.2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(1R,2S,5R)-2-isopropyl-5-methylcyclohexyl (2R,5R)-5-hydroxy-1,3-oxathiolane-2-carboxylate

EC Number:

604-569-1

Cas Number:

147126-62-3

Molecular formula:

C14H24O4S

IUPAC Name:

(1R,2S,5R)-2-isopropyl-5-methylcyclohexyl (2R,5R)-5-hydroxy-1,3-oxathiolane-2-carboxylate

Constituent 2

Reference substance name:

OS Menthol Ester

IUPAC Name:

OS Menthol Ester

Sampling and analysis

Analytical monitoring:

no

Test solutions

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Controls: medium only
- Evidence of undissolved material: Although OS MENTHOL ESTER is reported tobe insoluble in water the water-accommodated fraction (WAF) of the saturated stock suspension mixture of test item and dilution water was used for testing

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Straus)
- Method of breeding: Culturing and holding of the test species was conducted at the Stantec Labaratory (Guelph, ON), according to the Stantec SOP #230
(Stantec, 2004a). Daphnia cultures were maintained in 1 L polystyrene containers containing 900 mL of Stantec's Iabaratory dilution water (groundwater).
Culture temperature and photoperiod were identical to that of the test system (temperature 20 +- 2°C and a photoperiod of 16 hours light and 8 hours of darkness with a 30-minute transition period). Neonae test organisms were obtained from the stock cultures following the daily transfer of adult daphnids, to ensure that test organisms were of a uniform age, and less than 24 hours old.
- Feeding during test
- Foodtype: Two to four-week old adult daphnids were transferred to fresh water daily, andfed a 3:1 mixture of Selenastrum capricomutum and Chlorella
fusca (green algae) at a rate of 10 mUL (density of 3.5 X 107 cellslmL).
- Amount: The algal diet was supplemented with a suspension of YCT (yeast, Cerophyll, and commercial traut pellets ), fed daily at a rate of 5 mUL.
- Frequency: daily

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

220 ± 20 mg/L as CaCO3

Nominal and measured concentrations:

nominal: 1 030 mg/L, 473.6 mg/L, 217.9 mg/L, 100.2 mg/L, 46.1 mg/L, 21.2mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: all glass test aquaria of 250 mL volume filled
- Aeration: no
- No. of vessels per concentration (replicates): 4 (4)
- No. of vessels per control (replicates): 4 (4)

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Ground water
- Total organic carbon: < 0.5 mg/L
- Alkalinity: 236 mg/L
- Ca/Mg ratio: 61.4 mg Ca/L, 29.1 mg Mg/L
- Conductivity: 522 µS/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: Dissolved oxygen, pH, conductivity at start and end oftest, temperature and visual observations at 0, 24 and 48
hours, dilution water hardness at 0-hours.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: light/dark cycle was 16 to 8 h
- Light intensity: 400 to 800 LUX

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobilisation was monitored one and two days after exposure

Reference substance (positive control):

yes

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

250 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

87.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Mortality of control: all daphnids were mobile in the control during the 2 days of exposure.
- Any observations that might cause a difference between measured and nominal values: the test substance was insoluble in medium, the test concentrations were present as a clear solution

Results with reference substance (positive control):

Results with reference substance
- Results with reference substance valid? yes
- EC50/LC50: LC50 = 5.6 mg/L

Any other information on results incl. tables

	exposure period 0h				exposure period 24h				exposure period 48h
Immobility (per vessel)	a	b	c	d	a	b	c	d	a	b	c	d
Nominal conc. of test substance (mg/L)
0 (control)	0	0	0	0	0	0	0	0	0	0	0	0
21.2	0	0	0	0	0	0	0	0	0	0	0	0
46.1	0	0	0	0	0	0	0	0	0	0	0	0
100.2	0	0	0	0	1	2	4	1	3	4	4	2
217.9	0	0	0	0	3	1	1	2	5	2	2	5
473.6	0	0	0	0	5	5	5	5	5	5	5	5
1030	0	0	0	0	5	5	5	5	5	5	5	5

Applicant's summary and conclusion

Conclusions:

In this short-term toxicity study in daphnia magna an 48h EC50 value of 87.3 mg/L was found.