Decan-1-ol, ethoxylated

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

Please refer to the Category Approach Justification provided in Section 13

Reason / purpose for cross-reference:

read-across source

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.77 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other:

Remarks:

Source, WoE, C12 - C13 alcohol ethoxylates (EO 6.5), 1999

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1.75 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

immobilisation

Remarks on result:

other:

Remarks:

Source, WoE, C12 - C13 alcohol ethoxylates (EO 6.5), 1999

Reference 2

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented publication which meets basic scientific principles

Qualifier:

according to guideline

Guideline:

other: USEPA-TSCA (U.S. EPA, 1992)

Qualifier:

according to guideline

Guideline:

other: ASTM (1988) guidelines

GLP compliance:

no

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: waterflea
- Justification for species other than prescribed by test guideline: no
- Source: stock culture maintained at the University of Mississippi Ecotoxicology Laboratory
- Age of parental stock (mean and range, SD): less than 24 h
- Feeding during test
- Food type: Selenastrum sp. and Ankistrodesmus sp.
- Amount: 5 mL of concentrated algae of above stated species per daphnid
- Frequency: twice daily (in the morning and in the late afternoon)


ACCLIMATION
- Acclimation conditions (same as test or not): daphnids were allowed to acclimate to test temperature prior to introduction into exposure chambers.

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

mean: 77.5 mg/L as CaCO3 (range: 74.0 mg/L - 80.0 mg/L as CaCO3)

Dilution water with an average hardness of approximately 8 mg/L as CaCO3 was adjusted to 80 mg/L as CaCO3 by addition of calcium chloride and sodium bicarbonate.

Test temperature:

mean: 20.5 °C (range: 19.0 - 22.3 °C)

pH:

mean: 8.1 (range: 7.8 - 8.2)

Dissolved oxygen:

mean: 8.6 mg/L (range: 6.2 - 9.4 mg/L)

Nominal and measured concentrations:

nominal: 0.5, 1.0, 2.0, 3.0 and 6.0 mg/L
mean measured: 0.39, 0.77, 1.75, 2.69 and 5.21 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open / closed
- Material, size, headspace, fill volume: 250 mL borosilicate glass beakers with screened overflow outlets (100 µm mesh) that maintained solution volume at approximately 200 mL.
- Aeration: dilution water was aerated
- Type of flow-through (e.g. peristaltic or proportional diluter): FMI fluid-piston metering pumps (FMI Inc., New York, NY, USA)
- Renewal rate of test solution (frequency/flow rate): flow rates of each chamber were maintained at 2 mL/min by control valves, resulting in approximately 14 volume additions per chamber daily.
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: spring water collected daily from the University of Mississippi Biological Field Station.
- Alkalinity: mean: 72.4 mg/L as CaCO3 (range: 70.0 - 75.0 mg/L as CaCO3)
- Conductivity: mean: 325 µ/cm (range: 312 - 349 µ/cm)
- Intervals of water quality measurement: 3 - 5 days during exposure


OTHER TEST CONDITIONS
- Photoperiod: 16 h light : 8 h darkness

Reference substance (positive control):

no

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.77 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1.75 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

immobilisation

Details on results:

- Mortality of parent animals: 97% survival of the control organisms
- No. of offspring produced per day per female: control: see table below

Measured concentration [mg/L]	# Young
0	6.75
0.39	6.46
0.77	6.16
1.75	1.13^1
2.69	0.11^2
5.21	0^2

¹significantly different from control

²not included in reproduction NOEC calculation due to significant survival

effects (significantly different from control)

Description of key information

EC20 (21d) >= 3.72 - <= 6.55 mg/L for Daphnia magna reproduction (QSAR estimation)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

3.72 mg/L

Additional information

As no study is available for decan-1-ol, ethoxylated, 1-2.5EO (CAS 26183-52-8), a read-across is prepared to a chronic invertebrate study conducted with a similar alcohol ethoxylate (C12-13, 6.5 EO). This 21 days flow-through chronic experiment on Daphnia magna is conducted according to the guidelines USEPA-TSCA (U.S. EPA, 1992) and ASTM (1988) and is well documented in the publication by Gillespie et al. (1999). The reported NOEC for reproduction is 0.77 mg/L.

Nevertheless, the data allow not to derive a precise long-term effect value for the described mixture (decan-1-ol, ethoxylated, 1-2.5EO; CAS 26183-52 -8).

Alcohol ethoxylate specific QSARs were developed to describe the toxicity of varying mixtures (Wind & Belanger, 2006; Boeije et al., 2006; Belanger et al, 2006). The QSARs considered all three trophic levels (algae, invertebrates and fish). The effects are described as EC20 values, since the QSARs are more robust for the EC20 values than for NOEC or EC10 values (Boeije et al., 2006). For the described mixture decan-1-ol, ethoxylated, 1-2.5EO (CAS 26183-52-8) the QSAR for long-term toxicity on reproduction of Daphnia magna (Boeije et al., 2006) results in an EC20 (21d, reproduction) between 3.72 and 6.55 mg/L. This result is used as key information for the further assessment.