Reaction mass of nonyl methacrylate and decyl methacrylate and undecyl 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

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

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

At the start of the exposure and at renewal (0 and 24 hours), samples were taken from the freshly prepared WAF. At renewal and at the end of the exposure (24 and 48 hours), samples of the 24-hours old media were taken from the test vessels.
All samples were filled up to the top into the sampling vials (at least 20 mL) and closed immediately with crimp caps.

Vehicle:

no

Details on test solutions:

One water accommodated fraction (WAF) was prepared with a nominal loading of the test item of 100 mg/L. The loading levels are based on the results of a preliminary range finding test (non-GLP, open system).
The water accommodated fraction was prepared in a brown glass flask, which was filled with 2000 ml of dilution water. 227 μL of the test item (corresponding to 200 mg, when density of the test item of 0.88 g/cm3 is taken into account) were placed by pipette onto the surface of the dilution water. A slow stirring procedure was applied. Gentle stirring (to avoid formation of an emulsion) was carried out with a magnetic stirrer at room temperature for 24 ± 1 hour. After a separation phase of 1 hour, the aqueous phase or WAF was removed by siphoning (from the approximate bottom of the glass flask) via a glass tube (the glass tube was inserted in the dilution water before the test item was pipetted on the surface). The resulting water accommodated fraction (WAF) was used in a limit test. The WAF was checked via laser beam (Tyndall effect) for undissolved test item (formation of an emulsion). No Tyndall effect was observed.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Strain/clone: Daphnia magna STRAUS (Clone 5)
- Source: Breeder: Noack Laboratorien GmbH, Sarstedt, Germany (Institut für Wasser-, Boden- und Lufthygiene (WaBoLu), 14195 Berlin, Germany)
- Age of parental stock (mean and range, SD): Less than 24 hours old daphnids from a healthy stock were used for the study. Juvenile daphnids were removed from the culture vessels at the latest 24 hours before the start of the exposure and discarded. The juveniles born within the following period of max. 24 hours preceding the exposure were used for the test. No first brood progeny was used for the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

total hardness: 160 to 180 mg CaCO3/L

Test temperature:

18 - 22 °C (+/- 1°C)

pH:

7.3 - 7.6

Dissolved oxygen:

7.3 - 9.1

Nominal and measured concentrations:

Nominal loading 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers (50 ml)
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 20 ml
- Renewal rate of test solution (frequency/flow rate): The test solutions were renewed after 24 hours. For this purpose, a second set of test vessels was filled with the freshly prepared test solutions and the daphnids were transferred by pipette
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates):4
- No. of vessels per control (replicates): 4

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16/8 hours light/dark cycle
- Light intensity: diffuse light, light intensity of max. 1500 lx

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Basis for effect:

mobility

Details on results:

The WAF and the control were analytically verified via GC-MS in fresh media at the start of the exposure and at renewal (0 and 24 hours) as well as in 24-hours old media at renewal and at the end of the test (24 and 48 hours). The measured concentrations of the test item were 13.9 and 8.20 μg test item/L in the fresh media (0 and 24 hours) and < LOQ in the old media (24 and 48 hours).
All effect values are given based on the nominal loading of the test item C9-11 Methacrylate of 100 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

At the WAF with a nominal loading of 100 mg/L of the test item C9-11 Methacrylate, no effects on Daphnia magna STRAUS were observed.

Description of key information

An acute immobilization test with Daphnia magna (STRAUS) was carried out at the test facility to determine the effects of a Water Accommodated Fraction (WAF) with a nominal loading of 100 mg/L of the test item C9-11 Methacrylate according to OECD 202 (2004) which is equivalent to the Commission Regulation (EC) No.440/2008 Method C.2 (2008). The limit test was conducted under semi-static conditions over a period of 48 hours. The test item is a colorless, clear liquid. A water solubility of 40 μg/L ± 20 μg/L at 20 °C ± 0.5 °C was determined. Twenty daphnids (divided into 4 replicates with 5 daphnids each) were exposed to the WAF and the control. At the WAF with a nominal loading of 100 mg/L of the test item C9-11 Methacrylate, no effects on Daphnia magna STRAUS were observed.