Exo-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl methacrylate

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:

2010-01-24 to 2010-01-29

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

OECD 202, GLP, analytical monitoring.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

(2004)

Deviations:

no

Principles of method if other than guideline:

Acute Immobilization Test to Daphnia magna STRAUS to determine the effects of the saturated solution of the test item as a limit concentration after
24 and 48 hours of exposure under semi-static conditions.

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: STRAUS (Clone 5)
- Source: Institut für Wasser-, Boden- und Lufthygiene (WaBoLu), Germany
- Age at study initiation (mean and range, SD): less than 24 hours
- Length at study initiation (length definition, mean, range and SD): no data
- Weight at study initiation (mean and range, SD): mean weight: no data
- Method of breeding: Laboratory bred
- Feeding during test: daphnids were not fed during the test
- Food type: unicellular green algae e.g. Pseudokirchneriella subcapitata, Desmodesmus subspicatus and Cholorella vulgaris
- Amount: ad libitum
- Frequency: at least 5 times per week

ACCLIMATION
- Acclimation period: at least 2 hours in dilution water
- Acclimation conditions (same as test or not): in dilution water (ISO test water, according to OECD 202, Annex 3) of the same quality as used for
the test
- Health during acclimation (any mortality observed): no data

Test type:

semi-static

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

18 to 22 °C ± 1 °C constant

pH:

7.5 ± 0.1

Dissolved oxygen:

8.1 to 8.9

Nominal and measured concentrations:

0 and saturated concentration (maximum solubility level) corresponding to 2.57 mg/L (geometric mean measured concentration)

Details on test conditions:

- No solvent was used for preparing test concentrations: a saturated solution was prepared
- 20 daphnids were tested per concentration (5 per replicate).
- Control exposure: 4 replicates of dilution water (ISO test water, according to OECD 202) without test item was tested under the same conditions as
the test group
- Renewal rate of test solution (frequency/flow rate): medium renewal after 24 hours, no aeration

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 2.57 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: not applicable

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

> 2.57 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 2.57 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

2.57 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 2.57 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

- Results with reference substance valid: yes
- Referenz substance: Potassium dichromate
- EC50/LC50: 1.20 mg/L (95% confidence limit: 1.08 - 1.34 mg/L) after 24 hours

Immobilization Rates in the Definitive Test after 24 and 48 h of Exposure (n = 20, divided into 4 replicates with 5 daphnids each)

 

	Immobilisation [%]
	24 h					48 h
	Replicates					Replicates
	1	2	3	4	MV	1	2	3	4	MV
Control	0	0	0	0	0	0	0	0	0	0
Isobornyl methacrylate Saturated solution	0	0	0	0	0	0	0	0	0	0

MV = Mean value

Validity criteria fulfilled:

yes

Conclusions:

At the saturated solution level of Isobornyl methacrylate, which corresponded to the geometric mean measured concentration of 2.57 mg/L, no effect was observed.
Therefore In this valid guideline study (OECD 202, semi-static conditions), the 48 hr EC50 for Daphnia magna (STRAUS Clone 5) is > 2.57 mg/L .

Executive summary:

The 48–hr-acute toxicity of Isobornyl methacrylate to Daphnia magna straus was studied under semi static conditions according to OECD 202. Daphnids were exposed to control and saturated test chemical at a measured concentration of 0 and saturated concentration corresponding to 2.57 mg/L (geometric mean measured concentration) mg a.i./L for 48 hr. 

The concentrations of Isobornyl methacrylate were analysed in both the saturated test item solution and the control by HPLC in samples of the fresh media (0 and 24 hours) and the old media (at 24 and 48 hours). The recoveries of Isobornyl methacrylate in the saturated test item solution were determined to be 91 and 74 % of the initially measured values at 24 and 48 hours, respectively.

The water quality parameters (pH and dissolveed oxygen) were measured at 0, 24, and 48 hours and determined to be within the acceptable limits.

No immobilization was observed at the maximum concentration of the test item in this system.

Therefore the 48– hour EC₅₀was > 2.57 mg a.i./L.  The 48– hr NOEC based on immobilization/sublethal adverse effects was 2.57 mg a.i./L. 

 

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates.

 

Results Synopsis

 

Test Organism Age: Daphnia magna Straus, less than 24 hours old

Test Type: limit test, semi static, renewal after 24 hours, no aeration

 

NOEL:  2.57 mg a.i./L                       

EC₅₀: > 2.57 mg a.i./L                       95% C.I.: not applicable

Endpoint(s) Effected:  immobilisation

NOTE: Any of data in this dataset are disseminated by the European Union on a right-to-know basis and this is not a publication in the same sense as a book or an article in a journal. The right of ownership in any part of this information is reserved by the data owner(s). The use of this information for any other, e.g. commercial purpose is strictly reserved to the data owners and those persons or legal entities having paid the respective access fee for the intended purpose.

Description of key information

A reliable key study for Isobornyl methacrylate is available on short term

immobilization of aquatic invertebrates acc. OECD 202. EC50 (48h) on Daphnia magna was determined to be > 2.57 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2.57 mg/L

Additional information

A reliable key study is available on aquatic invertebrates: An OECD 202 study on Daphnia magnagives gives an EC50 -48h of > 2.57 mg/L. In a second OECD 202 study on Daphnia magna with limited documentation (only reliability:4), an EC50 -48h of 1.1 mg/l is reported.