Decan-1-ol, ethoxylated

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

activated sludge respiration inhibition testing

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

Please refer to the category approach justification provided in section 13.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

140 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks on result:

other: Source, key, 9002-92-0, Sasol, 1997, BH-97/04, activated sludge

Duration:

16.9 h

Dose descriptor:

EC50

Effect conc.:

> 10 g/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth inhibition

Remarks on result:

other: Source, supporting, 68439-50-9, Sasol, 1996, PZ-96/06, P. putida

Duration:

5 h

Dose descriptor:

EC50

Effect conc.:

> 2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Remarks on result:

other: Source, supporting, 68439-50-9, Sasol, 1996, SK-93/17, P. putida

Executive summary:

The toxicity to microorganisms is assessed on the basis of data from three studies with similar alcohol ethoxylates (C12, 4 EO, CAS 9002-92-0, C12 -14, 2 EO, CAS 68439 -50 -9 and C12-14, 6 EO, CAS 68439-50-9).

In a respiration test with domestic activated sludge according to EG-guideline 88/302/EG and GLP (Diefenbach, 1997), an EC50 (3h) of 140 mg/L was determined. This finding is supported by the results of a two tests with Pseudomonas putida that revealed an EC50 (16.9 hours) > 10 g/L and an EC50 (5 h) > 2 mg/l.

Reference 2

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 March 1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: EG Guideline 88/302/EG

Version / remarks:

30.05.1988

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Trade name: Marlowet BL

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

All test vessels were supplemented with 200 µl Baysilone as defoaming agent and vigorously stirred prior to the amendment of sludge.

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

Approximately 5 L activated sludge were taken from the municipal sewage treatment plant Marl-West, Germany, on the day before test start. The sludge was sedimented and washed with 1.5 L tap water and aerated for 10 min after additional sendimentation. The sludge was then suspended in 4 L of tap water and 200 mL synthetic sewage and was aerated and stirred. On the day of the test, the sludge material was washed twice and resuspended in 3 L tap water and had a dry weight of 3.82 g/L.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Hardness:

No details given

Test temperature:

20 ± 2 °C

pH:

test end: 8.1 - 8.2 in test substance and controls, 8.4 - 8.5 in reference controls

Dissolved oxygen:

test end at start of O2 measurement: 6.14 - 8.56 mg/L

Nominal and measured concentrations:

Nominal: 25, 50, 100, 150, 200 mg/L

Details on test conditions:

The test solutions in the vessels were continously stirred and aerated with clean, oil-free air (flow rate 0.5 - 1 L/min) to maintain a minimal concentration of 2.5 mg/L dissolved oxygen. All vessels contained 16 mL synthetic sewage and 200 mL inoculum and were filled to 500 mL with tap water after amendment of the emulsified test substance.
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 2

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Respiration rate after 3 h

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2x

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

140 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

- Controls: The difference between the two controls without test substance was 1.1%
- At the time of measurement the O2 consumption curve exhibited linearity

Results with reference substance (positive control):

- Results with reference substance valid: yes
- Relevant effect levels: EC50 = 6.7 mg/L

Conclusions:

An EC50 of 140 mg/l was found out for the inhibition of respiration of activated sludge.

Executive summary:

In a respiration test with domestic activated sludge according to EG-guideline 88/302/EG and GLP, an EC50 (3 h) of 140 mg/L was determined.

Reference 3

Endpoint:

toxicity to microorganisms

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

13 - 14 NOV 1996

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

DIN 38412-8 (Pseudomonas Zellvermehrungshemmtest)

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Pseudomonas putida

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

16.9 h

Test temperature:

21.1 - 21.2 °C

Nominal and measured concentrations:

nominal: 0.1, 1, 10, 100, 1000 and 10000 mg a.s./L

Details on test conditions:

TEST SYSTEM
- Test vessel: sterile 250 mL Erlenmeyer flasks
- Type (delete if not applicable): closed with cellulose stoppers
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6 growth controls, 1 pH-control, 1 blank

Reference substance (positive control):

no

Key result

Duration:

16.9 h

Dose descriptor:

EC10

Effect conc.:

> 10 g/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth inhibition

Key result

Duration:

16.9 h

Dose descriptor:

EC50

Effect conc.:

> 10 g/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth inhibition

Concentration [mg a.s./L]	Inhibition of cell growth (%)
0.1	-0.1
1	-0.3
10	-1.8
100	-0.7
1000	-4.6
10000	-7.4

Validity criteria fulfilled:

yes

Reference 4

Endpoint:

toxicity to microorganisms, other

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

Test 1: 19 - 20 OCT 1993; Test 2: 21 - 22 OCT 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

no guideline followed

Principles of method if other than guideline:

Oxygen consumption test according to a method developed by Hüls AG

GLP compliance:

yes

Specific details on test material used for the study:

Trade name: Marlipal 24/20

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Pseudomonas putida

Details on inoculum:

- Laboratory culture: in-house culture originally obtained from "Institut für Wasser-, Boden- und Lufthygiene des BGA (Berlin)"
- Preparation of inoculum for exposure: 200 mL steril medium was inoculated with 80 mL bacteria suspension (liquid culture of test organism, approximately 19 h incubation time, bacterial count approximately 10 x 10 exp. 5 bacteria/mL - extinction 436 nm: 0.29 - 0.31). Inoculum was aerated and stirred for 5 min.
- Initial biomass concentration: bacterial count approximately 10 x 10 exp. 5 bacteria/mL

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

5.33 h

Remarks on exposure duration:

1st test: 5.33 h; 2nd test: 5.5 h

Test temperature:

pre-culture:
Test 1: 24.8 - 25.0 °C
Test 2: 24.9 - 25.0 °C

incubation period:
test 1: 24.7 - 26.6 °C
test 2: 24.7 - 26.0 °C

Nominal and measured concentrations:

nominal: 100, 500, 1000 and 2000 µg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 100 mL BSB-bottles
- No. of organisms per vessel: 10 x 10 exp. 5 bacterial count
- No. of vessels per concentration (replicates): 4 (in two of them 1 mL HgCl3 was added for determination of the degree of autoxidation)
- No. of vessels per control (replicates): 5

Reference substance (positive control):

no

Duration:

5 h

Dose descriptor:

EC50

Effect conc.:

> 2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

No dose-response relationship of the test results, thus no EC10 available

Test	Concentration [µg/L]
	100	500	1000	2000
1	11.1%	7.3%	5.5%	2.6%
2	11.0%	9.6%	5.1%	4.5%

Description of key information

EC50 (3h) = 140 mg/L for activated sludge

EC50 (16.9h) > 10 g for Pseudomonas putida

Key value for chemical safety assessment

EC50 for microorganisms:

140 mg/L

Additional information

Since no data for decan-1-ol, ethoxylated, 1-2.5EO (CAS 26183-52-8) are available, toxicity to microorganisms is assessed on the basis of data from three studies with similar alcohol ethoxylates (C12, 4 EO; CAS 9002-92-0, C12 -14, 2 EO; CAS 68439-50-9 and C12-14, 6 EO; CAS 68439-50-9).

In a respiration test with domestic activated sludge according to EG-guideline 88/302/EG and GLP (Sasol, 1997), an EC50 (3h) of 140 mg/L was determined. This finding is supported by the results of a two tests with Pseudomonas putida that revealed an EC50 (16.9 hours) > 10 g/L and an EC50 (5 h) > 2 mg/L (Sasol, 1996 & Sasol, 1993).