2-(2-ethoxyethoxy)ethanol

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

1999

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Published study with original report also available. However, no analytical monitoring available. The fact that no clear dose response relationship was seen, that the NOEC derived is extraordinarily low compared to the consistent acute EC50 data from a number of studies (factor of ~250) and that the confidence limits are huge (factor of 600 from lower to upper limit) means that this study is not regarded as being sufficiently reliable as a key study and is disregarded from the derivation of the PNEC

Data source

Reference

Reference 1

Reference Type:

publication

Title:

"Effects of|ethylene glycol ethers on the reproduction of Ceriodaphnia dubia."

Author:

DeVillers, J., A. Chezeau, et al. (2003).

Year:

2003

Bibliographic source:

Chemosphere 50: 373-376.

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: draft AFNOR NF T90 - 376

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

yes

Remarks:

, different species. Only 7 days

Principles of method if other than guideline:

Note that the second reference, which is for a similar but different substance, contains some of the details of the methodology used that are reported here. Young organisms <24hrs old and from 2nd-5th brood of healthy adults are exposed to test solution.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-(2-ethoxyethoxy)ethanol

EC Number:

203-919-7

EC Name:

2-(2-ethoxyethoxy)ethanol

Cas Number:

111-90-0

Molecular formula:

C6H14O3

IUPAC Name:

2-(2-ethoxyethoxy)ethan-1-ol

Details on test material:

purity >= 99%;
Purchased from Sigma-Aldricht (Saint-Quentin Fallavier, France);

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

Analytical monitoring was not carried out because preliminary tests showed that that concentrations remained stable (due to the low volatility) between the 24hr renewals.

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Ceriodaphnia dubia

Details on test organisms:

TEST ORGANISM
- Source: Laboratoire INERIS
- Age of parental stock (mean and range, SD): 7-14 days
- Feeding during test: Yes
- Food type: Chlorella vulgaris 6E6 cells/50ml; Raphidocelis subcapitata 3E6 cells/50ml; commercial fish food 5g/l

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

7

Test conditions

Hardness:

250 +/- 20 mg/L as CaCO3

Test temperature:

25 +/- 2°C, monitored continuously.

pH:

~8

Dissolved oxygen:

Disolved oxygen measured daily except weekends

Nominal and measured concentrations:

5 concentrations, not specified. The highest concentration tested was the NOEC from acute toxicity studies using daphnia magna (see chapter 6.1.3)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: glass, 90ml size, 50ml fill.
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): daily, except weekends (either not day 1/2 or 2/3)
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10
- No. of vessels per vehicle control (replicates):

TEST MEDIUM / WATER PARAMETERS after aeration (typical)
- Source/preparation of dilution water: Evian mineral water
- Metals: 108mg/l (measured ions)
- Chloride: 4.5mg/l
- Ca 78mg/l
- Mg 24mg/l
- Na: 5mg/l
- K 1mg/l
- Sulphate 10mg/l
- Conductivity: 400 +/- 50uS/cm
- Hardness: 200mg CaCO3/l
- O2: >7mg/l
- pH: 8.3

OTHER TEST CONDITIONS
- Photoperiod: 16:8 light:dark photoperiod was employed
- Light intensity: (300-500 lux.);
- Test solutions renewed daily from day 3

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : parental mortality and number of offspring per alive parent (10% inhibition);

Results and discussion

Effect concentrations

Duration:

7 d

Dose descriptor:

EC10

Effect conc.:

7.38 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 0.14 - 89.21mg/l (95% CL)

Results with reference substance (positive control):

Sodium pentachlorophenate, copper(II) sulphate pentahydrate within normal ranges.

Reported statistics and error estimates:

EC values calculated using TOXSTAT v3.5 using Hill method. NOEC calculated using Bonferroni test

Any other information on results incl. tables

The 95% confidence interval is very wide, covering between 1 and 2 orders of magnitude.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

control survival >80%, less than 20% of males at day 7 per batch, >60% of control females had >=3 broods, control females producing an average of 15 offspring each by day 7. Reference compound results within historic ranges.

Executive summary:

In a semi-static study carried out to an AFNOR protocol (similar to an OECD guideline study but shorter duration), Ceriodaphnia Dubai were exposed to 2 -(2 -ethoxyethoxy)ethanol for 7 days. An EC10 for reproduction of 7.38mg/l was established.