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Ecotoxicological information

Short-term toxicity to aquatic invertebrates

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Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1997-10-18 to 1997-10-20
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
Good study conducted according to guideline equivalent to OECD 202 with GLP compliance, but no analytical monitoring.
Qualifier:
according to guideline
Guideline:
other: DIN 38412, part 1
Deviations:
no
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
no
GLP compliance:
yes
Analytical monitoring:
no
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: The test substance is poorly soluble, however a fine-turbid suspension could be prepared using slightly prewarmed demineralised water (23 to 25 degC); for this purpose, the test substance and the prewarmed water were given into the vessels and manually shaken for 3 minutes. Four parallel suspensions were prepared. Each of 4 shaking funnels was filled with 250 ml prewarmed demineralised water and 25 mg test substance. The funnels were shaken at a frequency of 110 - 120 /min for 24 hours protected from light at room temperature and then placed vertically for at least 2 hours. the content, without the upper layer, was transferred into a glass flask. The produced suspensions were not filtered, remained stable even at a temperature of 20 degC and could be diluted.

- Controls: no treatment.
Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM

- Common name: water flea

- Strain: Daphnia magna

- Source: Institut fur Wasser-, Boden-, und Lufthygiene

- Feeding during test: no


ACCLIMATION

- Acclimation period: >1 week

- Acclimation conditions: dilution water used in the test is the same as holding water

- Type and amount of food: Algae and a small amount of aerated sewage

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h
Post exposure observation period:
none
Hardness:
250 mg CaCO3/L
Test temperature:
20 degC
pH:
mean = 7.9
Dissolved oxygen:
>80% maximum saturation
Salinity:
N.A.
Nominal and measured concentrations:
Nominal: Control, 0.178, 0.316, 0.562, 1.00, 1.78, and 3.16 mg/L
Details on test conditions:
TEST SYSTEM

- Test vessel: flask

- Material, size, headspace, fill volume: glass vessels, diameter: 38 mm, height: 60 mm, fill volume: 50 mL

- Aeration: not reported

- No. of organisms per vessel: 5

- No. of vessels per concentration (replicates): 4


TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: Reconstituted, aerated, fully demineralised water

- Total organic carbon:

- Alkalinity: 0.8 mmol/L

- Ca/mg ratio: 4:1

- Culture medium different from test medium: no

- Intervals of water quality measurement: pH and DO were measured at the start and the end of study in each vessel,, the temperature was monitored continuously.


OTHER TEST CONDITIONS

- Adjustment of pH: none

- Photoperiod: 16 hours light/8 hours darkness white type fluorescent light

- Light intensity: 500 lux (approx.) (approx. 0.045 x 10^20 photons/m^2 x s)


EFFECT PARAMETERS MEASURED: Immobilisation
Reference substance (positive control):
no
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
0.316 mg/L
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.765 mg/L
Duration:
48 h
Dose descriptor:
EC100
Effect conc.:
1.78 mg/L
Details on results:
- Mortality of control: 0%
Reported statistics and error estimates:
The EC50 was calculated by means of linear regression analysis.

Table 1. Immobilisation of D. magna exposed to 1-dodecanol (%).

 Nominal concentrations (mg/L)  24 h  48h
 Control  0  0
 0.178  0  0
 0.316  0  0
 0.562  0  10
 1.00  40  80
 1.78  90  100
 3.16  100  -

A 100% mortality was achieved at 1.78 and 3.16 mg/L after 48h.

Validity criteria fulfilled:
yes
Conclusions:
A 48 h EC50 value equivalent to 0.765 mg/L has been determined for the effects of the test substance on immobilisation of Daphnia magna.
Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Remarks:
Not key study: Other studies (same reliability score) showing greater toxicity but with standard test organisms are available
Principles of method if other than guideline:
Method: other
GLP compliance:
not specified
Analytical monitoring:
not specified
Test organisms (species):
Nitocra spinipes
Test type:
static
Limit test:
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
1 mg/L
Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
documentation insufficient for assessment
Remarks:
Only a summary report was available for review.
Principles of method if other than guideline:
Method: other
GLP compliance:
not specified
Analytical monitoring:
no
Test organisms (species):
Daphnia magna
Test type:
static
Limit test:
no
Duration:
48 h
Dose descriptor:
EC0
Effect conc.:
100 mg/L
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
320 mg/L
Duration:
48 h
Dose descriptor:
EC100
Effect conc.:
1 000 mg/L
Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1992-12-15 to 1994-07-12
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
Study conducted according to guideline equiavelnt to OECD 201. Methodology for preparing concentrations of test substance in solution was a serial dilution from a stock solution, concentration not reported, of a poorly soluble substance, which was manually dispersed in solution. However the results are reported with respect to measured concentrations.
Qualifier:
according to guideline
Guideline:
other: Snell & Moffat (1992)
Deviations:
yes
Remarks:
modifications: diet, water source, and light level were changed to better reflect conditions in the natural environment.
GLP compliance:
yes
Analytical monitoring:
yes
Details on sampling:
- Concentrations: not reported

- Sampling method: samples were stored daily
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: the method of preparation of test solution was not reported

- Chemical name of vehicle (organic solvent, emulsifier or dispersant): a solvent was reported to have been used if necessary. The test was conducted on 22 substances and the solvent name and concentration were not reported, nor which substances it was applied to.

- Evidence of undissolved material: the test substance was tested up to limit of solubility, evidence of undissolved material was not reported.
Test organisms (species):
other: rotifer: Brachionus calyciflorus
Details on test organisms:
TEST ORGANISM

- Source: Bioresponse Systems Inc., Halifax, Nova Scotia

- Age at study initiation (mean and range, SD): <3h old

- Method of breeding: approx 3000 cysts were hydrated with dilution water 20 hours prior to test initiation.

- Feeding during test

- Food type: algae: C. vulgaris and S. capricornutum

- Amount: algae were centrifuged out of media and resuspended in dilution water in equal amounts, concentration not reported.

- Frequency: organisms inoculated with algae


ACCLIMATION

- Acclimation period: cysts were grown in the laboratory building 20 hours before the test

- Acclimation conditions (same as test or not): yes

- Type and amount of food: algae as above, amount not reported.
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h
Post exposure observation period:
none
Hardness:
152.1 mg/L as CaCO3
Test temperature:
25 +/- 2 deg C
pH:
8.55
Dissolved oxygen:
8.5 mg/L
Salinity:
not reported
Nominal and measured concentrations:
Nominal concentrations: 4-6 nominal concentrations. The compound was tested up to its solubility limit, the actual concentrations were not reported.
Measured concentrations: the EC50 is expressed realtive to measured concentrations, which is the time weighted average of exposure concentrations, because, out of the 22 chemicals tested, concentrations decreased by 20-90% in the 48h test.
Details on test conditions:
TEST SYSTEM

- Test vessel: not reported, but placed on a rotator

- Fill volume: 10 ml of test water

- No. of organisms per vessel: 6

- No. of vessels per concentration (replicates): 3

- No. of vessels per control (replicates):3


TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: 50/50 blend of locally obtained well water and reverse osmosis water

- Conductivity: 449.7 umhos

- Culture medium different from test medium: yes

- Intervals of water quality measurement: beginning and end of test


OTHER TEST CONDITIONS

- Photoperiod: 16/8 hour light dark cycle



EFFECT PARAMETERS MEASURED: mortality measured as absence of activity after 48h


TEST CONCENTRATIONS

- Spacing factor for test concentrations: not reported
Reference substance (positive control):
yes
Remarks:
pentachlorophenol and copper
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.81 mg/L
Nominal / measured:
meas. (TWA)
Conc. based on:
not specified
Basis for effect:
other: inactivity
Remarks on result:
other: (0.767.1.02)
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.88 mg/L
Nominal / measured:
meas. (TWA)
Conc. based on:
not specified
Basis for effect:
other: inactivity
Remarks on result:
other: (0.767-1.02)
Details on results:
- Mortality of control: raw data was not presented in the report, nor was information on validity criteria

- Effect concentrations exceeding solubility of substance in test medium: test substance was dissolved in test solutions up to the limit of solubility.
Results with reference substance (positive control):
- Results with reference substance valid? no data

- EC50: pentachloropenol: 1.3 mg/L; Cu NOEC = 0.012 mg/L, LOEC = 0.023 mg/L
Reported statistics and error estimates:
EC50s were estimated by the iterative nonlinear regression technique described by Bruce and Versteeg (1992). All statistical tests were performed with SAS, version 6.0.

The test was performed on 22 substances and the aim was to determine the efficacy of QSAR predictions when modifying original guideline by Snell & Moffat (1992), mainly with surfactants.

Validity criteria fulfilled:
not specified

Description of key information

Short-term toxicity to aquatic invertebrates: 48 hour EC50 0.765 mg/l (nominal) in accordance with test guideline DIN 38412, part 1 (Daphnia magna).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates
Effect concentration:
0.765 mg/L

Additional information

Reliable values for short-term toxicity to invertebrates are available. These data indicate an EC50 in the range 0.7-1.0 mg/l in freshwater and brackish/marine species. The lowest reliable result is a 48 h EC50 value of 0.765 mg/L for the effects of dodecanol on the mobility of Daphnia magna. This value has been selected as key.

These results are supported by consistent values in other studies with aquatic invertebrate species:

Freshwater species:

48 h EC50 (Branchionus calyciflorus) = 0.81-0.88 mg/l [P&G, 1996].

48 h EC50 (Daphnia magna) = 320 mg/l (reliability 4) [Henkel KGaA, 1999].

 

Marine and brackish species:

96 h LC50 (Nitocra spinipes) = 1 mg/l [Linden et al. 1979, Bengtsson, Renberg and Tarkpea, 1984].

 

Discussion of trends in the Category of C6-24 linear and essentially-linear aliphatic alcohols:

Linear LCAAs

The data presented in the table below show the toxicity of the linear LCAAs to increase from an EC50 of 200 mg/L for C6 to 0.77 mg/L for C12. Effects have also been observed in tests with C13 and C14 LCAAs but at concentrations that exceeded the solubility of the alcohols. Although not explicitly identified in the test reports, physical effects (rather than true toxicity) cannot therefore be excluded from the interpretation of the results for these two LCAAs. In the Unilever (1994) study with C14 the authors have recorded that the test substance adhered to the daphnids at concentrations higher than the water solubility of 1-tetradecanol. This indicates that physical fouling is likely to have caused the effects seen at the EC50 value of 4 mg/L.

 

The lowest reliable short-term EC/LC50 values for invertebrates exposed to linear LCAAs are presented in the following table.


Table: Key studies for invertebrate short-term toxicity studies on single carbon chain length linear LCAAs.

CAS #

Chemical name

Comment

Water solubility (mg/L)

Species

Method/ Guideline

Exposure regime

Endpoint

Value (mg/L)1

Reliability code

Reference

111-27-3

1-Hexanol

 

5900 at 20°C

Daphnia magna

Not specified

Static

24 h EC50

200 (n)

2

Bringmann and Kuhn, 1982

111-70-6

1-Heptanol

SUPPORTING

1300 at 20°C

D. magna

Not specified

Static

24 h EC50

82 (n)

2

Bringmann and Kuhn, 1982

111-87-5

1-Octanol

 

550 at 25°C

D. magna

Not specified

Static

24 h EC50

20 (n)

2

Bringmann and Kuhn, 1982

143-08-8

1-Nonanol

 

130 at 20°C

Nitocra spinipes (brackish)

Not specified

Static

96 h EC50

25 (n)

2

Bengtsson, Renberg, and Tarkpea, 1984

112-30-1

1-Decanol

 

40 mg/L at 20°C

N. spinipes (brackish)

Not specified

Static

96 h EC50

3.1 (n)

2

Bengtsson, Renberg, and Tarkpea, 1984

68516-18-7

Decene, hydroformylation products

Supporting.hydroformylation product (=C11)

No data

D. magna

EPA 1975

Static

48 h LC50

4.2 (n)

2

Burgess and Forbis, 1983b

112-42-5

1-Undecanol

 

8.0 at 20°C

N.spinipes (brackish)

Not specified

Static

96 h LC50

0.8-1.1 (n)

2

Bengtsson, Renberg, and Tarkpea, 1984

112-53-8

1-Dodecanol

 

1.9 at 20°C

D. magna

DIN 38412

Static

48 h EC50

0.77 (n)

2

Laboratory of Pharmacology and Toxicology, 1997

112-70-9

1-Tridecanol

SUPPORTING

0.38 at 20°C

D. magna

Not specified

Not specified

EC50 (duration unknown)

0.51 (>LoS)

4

Unilever, 1995

112-72-1

1-Tetradecanol

 

0.19 at 25°C

D. magna

Not specified

Not specified

48 h EC50

3.2

(>LoS)

2

Unilever, 2010

Notes:

1>LoS: LC50 observed was greater than the limit of solubility (n) based on nominal concentrations, (m) based on measured concentrations.

SUPPORTING denotes that the substance is not for registration but the data are used to support the category


Multi-constituents LCAAs

The data presented in the table below show the multi-constituent substances containing LCAAs with carbon numbers in the ranges of C7-9 to C12-15 to exert short-term toxicity at concentrations of between 0.23 and 30 mg/L. At these concentrations it is likely that all constituents will have been fully dissolved. The short-term EC50 of the C14-15 LCAAs to aquatic invertebrate was determined to be above the limit of solubility of the substance.

For the C12-14 and C12-18 multi-constituent substances there was evidence of toxic effects in tests conducted on test media prepared as water-accommodated fractions at loading rates that exceeded the solubility of some constituents. For the C16-18 substance there was evidence of effects in test media that could have contained undissolved test material. The possibility of physical effects (rather than true toxicity) contributing to the observed effects were not discussed in the test report but cannot be excluded.

 

The lowest reliable short-term EC/LC50 values for invertebrates exposed to multi-constituent LCAAs are presented in the following table.


Table: Invertebrate short-term toxicity studies on mixed carbon chain length (multi-constituent) LCAAs (species are freshwater unless noted otherwise).

CAS #

Chemical name

Comment

Water solubility (mg/L)

Species

Method/ Guideline2

Exposure regime

Endpoint

Value (mg/L)3

Reliability code

Reference

 

Alcohols, C7-9

SUPPORTING

510 mg/L at a loading rate of 1000 mg/L (estimated)

Daphnia magna

OECD 202

Semi-static

48 h EC50

5.9

1

Fraunhofer Institute, (2005e)

Mixture of 68527-05-9 and 70955-11-2-

Mixture of hexane and octene hydroformylation products

i.e. alcohols, C7-9
SUPPORTING

No data

D. magna

EPA 1975

Static

48 h LC50

30 (n)

2

Burgess and Forbis, 1983c

 68515-81-1

Nonanol, branched and linear

 Read-across from C9

121 (estimated)

Nitocra spinipes(brackish)

Not specified

Static

96 h EC50

25 (n)

2

Bengtsson, Renberg, and Tarkpea, 1984

 66455-17-2

Alcohols, C9-11

SUPPORTING

44 at a loading rate of 1000 mg/L. (estimated)

D. magna

Not specified

Static

48 h EC50

7 (n)

2

Shell Research Limited, 1983

 66455-17-2

Alcohols, C9-11

SUPPORTING

44 at a loading rate of 1000 mg/L. (estimated)

Crangon crangon(marine)

UK MAFF

Semi-static

96 h LC50

4.6 (n)

2

Huntingdon Life Sciences Ltd. 1991a.

66455-17-2

Alcohols, C9-11

SUPPORTING

44 at a loading rate of 1000 mg/L. (estimated)

Daphnia magna

Not specified

Static

48 h EC50

8.5 (not specified)

2

Shell Research Limited, 1982

 

Alcohols, C9-11 (odd numbered), branched and linear

 

26.04 at 20°C

Daphnia magna

OECD 202

Semi-static

48 h EC50

0.39 (m)

1

Hydrotox, 2017

Mixture of 68516-18-7, 68527-05-9 and 70955-11-2-

Mixture of octane and decene hydroformylation products

SUPPORTING

No data

D. magna

EPA 1975

Static

48 h LC50

11 (n)

2

Burgess and Forbis, 1983d

 90342-32-8

Decanol, branched and linear

 Read-across from C10

26.17 at 20°C

N. spinipes(brackish)

Not specified

Static

96 h EC50

3.1 (n)

2

Bengtsson, Renberg, and Tarkpea, 1984

 128973-77-3

Undecanol, branched and linear

 

Reaction mass of 2-methyldecan-1-ol and 2-propyloctan-1-ol and 2-ethylnonan-1-ol and 2-butylheptan-1-ol

 Read-across from C11

6.3 at 25°C

N. spinipes(brackish)

Not specified

Static

96 h LC50

0.8-1.1 (n)

2

Bengtsson, Renberg, and Tarkpea, 1984

 740817-83-8

Alcohols, C12-13-branched and linear

 

2.4 at 25oC

D. magna

OECD 202 WAF

Static

48 h EL50

0.23(n)

1

Shell, 2000a

 75782-87-5

Alcohols, C12-13

 

2.4 at 25oC

C. crangon(marine)

UK MAFF

Semi-static

96 h LC50

>10 (n) (>LoS)

2

Huntingdon Life Sciences Ltd. 1991b.

 740817-83-8

Alcohols, C12-13-branched and linear

 

2.9-3.1 at 20°C

D. magna

OECD 202 WAF

Static

48 h EL50

2.8 (n)

1

TNO, 2000b

80206-82-2

Alcohols, C 12-14

Type A
SUPPORTING

4.6 predicted at 1000 mg/L loading rate

D. magna

EU 92/69/EWG WAF

Static

48 h EL50

63 (n) (>LoS)

1

Henkel, 1998b

90604-40-3

Alcohols, C12-15-branched and linear

 

0.80 at 20°C

D. magna

OECD 202 WAF

Static

48 h EL50

<1.0 (n) <0.2 (m)

1

Shell, 2001a

67762-25-8

Alcohols, C 12-18

Type A
SUPPORTING

1.7 predicted at 100 mg/L loading rate

D. magna

EU 92/69/EWG

Static

48 h EL50

40 (n) (>LoS)

1

Henkel, 1998a

68002-94-8

Alcohols, C 16-18 and 18 Unsaturated 

SUPPORTING

0.044 predicted at 1000 mg/L loading rate

D. magna

EU Guideline 92/69/EWG

Static

48 h EC50

70 (n) (>LoS)

2

Henkel KGaA. 1995.

Notes:

1Compositional Types are described in section 1.5 of the ecotoxicity category report.

2WAF denotes test medium was a water-accommodated fraction

3>LoS: EC50 observed was greater than the limit of solubility of at least some constituents of the substance. (n) based on nominal concentrations, (m) based on measured concentrations.

SUPPORTING denotes that the substance is not for registration but the data are used to support the category

n/a denotes not applicable


The data for nonanol, branched and linear, decanol branched and linear, decanol branched and undecanol branched and reaction mass of 2-methyldecan-1-ol and 2-propyloctan-1-ol and 2-ethylnonan-1-ol and 2-butylheptan-1-ol alcohols have been read-across from their linear LCAAs counterparts (C9, C10 and C11) since they are essentially linear LCAAs.

The measured data do not permit a definite toxicity cut-off to be identified for the single carbon number LCAAs or the multi-constituent substances. This is because the potential for physical effects to contribute to the results obtained for the C13 and 14 single carbon number alcohols, and the multi-constituent substances containing constituents with carbon numbers that are all >C12, cannot be excluded. However, it is reasonable to conclude from the data that are presented that it is unlikely that linear LCAAs with carbon numbers >C13 and multi-constituent LCAAs with carbon numbers all >C13 would be toxic.

 

References

 

Bengtsson, B., Renberg, L., and Tarkpea, M. (1984). Molecular structure and aquatic toxicity-An example with C1-C13 aliphatic alcohols. Chemosphere 13(5/6):613-622.

 

Bringmann, V. and Kuhn, R.1982. Results of toxic action of water pollutants on Daphnia magna Straus tested by an improved standardized procedure. Z. Wasser Abwasser Forsch. 15(1):1-6.

 

Burgess, D. and Forbis, A.D. 1983b. Acute toxicity of oxo alcohol 1100 to Daphnia magna. Static acute bioassay report 30851.

 

Burgess, D. and Forbis, A.D. 1983d. Acute toxicity of oxo alcohol 7911 to Daphnia magna. Static acute bioassay report 30848.

 

Burgess, D. and Forbis, A.D. 1983c. Acute toxicity of oxo alcohol 7900 to Daphnia magna. Static acute bioassay report 30845.

 

Fraunhofer Institute, 2005a, Daphnia, acute immobilization, Linevol 79. Study SDA-04/4-20, Fraunhofer Institute.

 

Henkel, 1998a. Henkel Report No. R9800103.

 

Henkel,1998b. Henkel KGaA Report No. R9800104.

 

Henkel KGaA., 1995. Report No. 9400262. May 1995.

 

Huntingdon Life Sciences Ltd.(HLS).1991a. Report No. SLL 207(a)/91714.

 

Huntingdon Life Sciences Ltd.(HLS).1991b. Report No. SLL 207(b)/91602.

 

Laboratory of Pharmacology and Toxicology. 1997. Examination of 1-Dodecanol in an acute immobilization test in Daphnia magna. LPT Report No. 10762/97.

 

Shell, 2000a. Shell. RTS Report No. CT.00.47050.

 

Shell, 2001a. Shell. RTS Report No. OG.01.49011.

 

Shell Research Limited, 1983. Toxicity tests with Daphnia magna: Acute toxicity of eight test materials to a newly-introduced strain of D. magna in reconstituted fresh water. Shell Research Limited, Sittingbourne Research Centre. SBGR.83.100.

 

TNO Nutrition and Food Research Institute. 2000b. Static acute toxicity test with compound 33A abd the crustacean species Daphnia magna. TNO report V98.1320.

 

Unilever, 1995. Acute toxicity of 1-tetradecanol to Daphnia magna. Unilever. Study AT/ALC/BK4.

 

Unilever, 2010. The Acute toxicity of 1-tetradecanol to Daphnia magna. Testing laboratory: Unilever Port Sunlight Research Laboratory, Quarry Road East, Bebington, Wirral Merseyside, L63 3JW, UK. Owner Company: Unilever. Company study no.: AT/ACL/BK4. Report date: 2010-08-01 (2010 study report summarising a 1994 study).