Fatty acids, C10-12, esters with polylactic acid, sodium salts

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:

August-14-16, 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study was performed according to GLP requirements. Chemical analysis was performed at a laboratory approved by the Swedish Medical Products Agency to be in compliance with Good Manufacturing Practice according to GMP guidelines laid down in Directive 2003/94/EC.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

EU Method C.2. Acute toxicity for daphnia

Deviations:

no

Remarks:

no

Qualifier:

according to guideline

Guideline:

ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0,2,5,10,20,50 mg/L
- Sampling method:Samples were collected from test solutions at t(0), t(24h) old and new solutions, t(48h) termination of test
- Sample storage conditions before analysis: Samples of 40 ml were stored in 50 ml glass bottles and stored at -20°C +/- 2.0°C

Vehicle:

no

Details on test solutions:

Test medium: ISO-medium prepared from MQ water and salts were added to the water according to the standard procedure. pH was 7.9 and hardness was 250 +/- 25 mg/L expressed as CaCO3.
Test solutions: Stock solution of 50mg/L was prepared at t(0) and t(24) by weighing out 50 mg of test product and dissolving it in 1 L of test medium. pH was adjusted from 7.4-7.9 at t(0) and from 7.3-7.7 (t=24h) with one droplet of 1 M NaOH. The test solutions of minor concentrations were prepared by diluting appropate amounts of the stock solution in the test medium.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: Straus
- Source: Langedam, Birkerod, cultured at DHI since 1979
- Age at study initiation (mean and range, SD): < 24 h

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

250 +/- 25 mg/L expressed as CaCO3

Test temperature:

20.3 +/- 0.4°C

pH:

7.8 - 8.0

Dissolved oxygen:

Start: 100% saturation
End: 99% saturation

Salinity:

n.a.

Nominal and measured concentrations:

Nominal concentrations: 0, 2,5,10,20 and 50 mg/L
Measured concentration: (Average based on measurement of 10,20 and 50 mg/L nominal concentration at 0,24(old/fresh) and 48h , n=4))
10.6, 27.4, 46,5 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 50 ml glass beakers with 25 ml of test solution
- Type (delete if not applicable): closed
- Aeration: none
-Renewal rate of test solution (frequency/flow rate): At t(24h) the test solution were renewed
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates):4
- No. of vessels per control (replicates): 6
- Biomass loading rate: ca. 1 daphnia/5 ml test medium

TEST MEDIUM / WATER PARAMETERS
- Intervals of water quality measurement: daily

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: none
- Light intensity: total darkness

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobilisation at t(24h) and t(48h)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Justification for using less concentrations than requested by guideline: n.a.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (K2Cr2O7)

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

29 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

dissolved

Basis for effect:

mobility

Remarks on result:

other: 25-32

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

34 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

dissolved

Basis for effect:

mobility

Remarks on result:

other: 30-42

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

21 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: n.d.

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

27 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 22-n.d.

Details on results:

- Behavioural abnormalities: none
- Mortality of control: 0
- Other adverse effects control: none
- Abnormal responses: no
- Effect concentrations exceeding solubility of substance in test medium: no, water solubility of test substance is 0,12 g/L

Results with reference substance (positive control):

EC10 (24h): 1.1 mg/L
EC50 (24h): 1.6 mg/L
Validity is fulfilled. The EC50 value (24h) of the reference substance potassium chromate is within the range specified in ISO 6341 (0.6-2.1 mg/L)

Reported statistics and error estimates:

EC values for test product and reference substance were calculated by use of the standard procedure Probit Analysis.
Chi-square statistic for heterogeneity of variance is calculated, and the tablular value at the 0.05 level.
Estimated EC10 and EC50, and associated 95% confidence limits

Table 1 Test results

Nominal concentration [mg/L]	Total number of animals per concentration	Number of immobile after 24 h	Number of immobile after 48 h
Control	30	0	0
2	20	0	0
5	20	0	0
10	20	0	0
20	20	0	1
50	20	15	20

Table 2: Validity criteria for OECD 202.

Criterion from the guideline	Outcome	Validity criterion fulfilled
In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.	0%	yes
The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.	Start: 100% saturation End:   99% saturation	yes

 

 

Validity criteria fulfilled:

yes

Remarks:

please refer to "Any other information on results incl. tables"

Conclusions:

EC10 (24h): 33 mg/l
EC 10 (48h): 29 mg/L
EC50 (24h): 29 mg/L
EC50 (48h): 34 mg/L

Executive summary:

The test was performed to specify the acute toxic effects of the reaction products of racemic lactic acid, partially neutralized with sodium hydroxide, and decanoic acid and dodecanoic acid on the crustacean Daphnia magna. The test was carried out in fully accordance with OECD 202 Daphnia sp.; Acute immobilization test further specified in ISO Standard 6341 Water quality - determination of the inhibition of the mobility of Daphnia magna STRAUS (Cladocera, Crustacea)-Acute toxicity test.

OECD 202 also corresponds to EU testing Method C.2. Acute toxicity for daphnia.

Number of immobilized animals was recorded after 24h and 48 h.

Postive control was performed by using Potassium dichromate.

No deviations to study protocol are documented.

Result: EC 50 (24h): 29 mg/L; EC 50(48h): 34 mg/L

Description of key information

EC50 (48h): 34 mg/L (arith. mean, measured OECD 202)

Additional information

One study investigating the acute toxicity to aquatic invertebrates is available. The study was performed with a semi-static test regime following OECD guideline 202 and GLP. Daphnia magna were exposed to nominal concentrations of 2, 5, 10, 20 and 50 mg/L. The test solutions were renewed daily. Analytical dose verification of the three highest test concentrations was performed (HPLC) with newly prepared and old test media. The arith. mean measured concentrations were 10.6, 27.4, 46,5 mg/L. Immobilisation was observed at the highest test concentration. The determined EC50 (48 h) was 34 mg/L (arith. mean measured concentration).