2-butyl-2-ethylpropanediol

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

8 April 1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline compliant study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

no

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

2-butyl-2-ethylpropanediol

EC Number:

204-111-7

EC Name:

2-butyl-2-ethylpropanediol

Cas Number:

115-84-4

Molecular formula:

C9H20O2

IUPAC Name:

2-butyl-2-ethylpropane-1,3-diol

Constituent 2

Reference substance name:

2-Butyl-2-ethyl-1,3-propanediol (BEPD)

IUPAC Name:

2-Butyl-2-ethyl-1,3-propanediol (BEPD)

Details on test material:

- Name of test material (as cited in study report): BEPD and BEDP
- Physical state: white solid
- Analytical purity: >99%
- Water solubility: 8 g/L at 20°C
- Volatility: <2.0 Pa at 20°C

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Sampling and analysis

Analytical monitoring:

not required

Details on sampling:

Not applicable

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

activated sludge

Details on inoculum:

Obtained from Louddens municipal sewage plant, Stockholm, Sweden and sampled on April 8, 1998. The sludge contained 20 g dry matter/L after prescribed washing and centrifugation.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Post exposure observation period:

Not applicable

Test conditions

Hardness:

Not applicable

Test temperature:

Not reported

pH:

Not applicable

Dissolved oxygen:

Not reported

Salinity:

Not applicable

Nominal and measured concentrations:

concentration of BEPD used: 0 , 51.5, 103, 258, 515 and 2575 mg/L, calcuated from total organic carbon (TOC).

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

650 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Effect concentrations 2

Duration:

3 h

Dose descriptor:

other: EC20

Effect conc.:

50 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Effect concentrations 3

Duration:

3 h

Dose descriptor:

other: EC80

Effect conc.:

2 600 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Results with reference substance (positive control):

3,5-dichlorophenol was tested at 1, 5, 10 and 25 mg/L. Inhibition of respiration compared to the control after 3 hours was 27, 45, 62 and 86% at 1, 5, 10 and 25 mg/L.

Reported statistics and error estimates:

3 hour EC50 was determined from a plot (log normal).

Any other information on results incl. tables

Results of the definitive test

BEPD (mg/L) calculated from TOC	Inhibition of respiration related to control (%) 30 mins		Inhibition of respiration related to control (%) 3 hours		Reference 3,5-dichlorophenol (mg/L)	Inhibition of respiration related to control (%) 3 hours
0	0	0	0	0	0	0
51.5 (1%)	19	22	21	22	1	27
103 (2%)	25	28	26	28	5	45
258 (5%)	42	44	42	35	10	62
515 (10%)	42	48	46	49	25	86
2575 (25%)	79	76	80	82

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

The EC50 for the reference inhibitor, 3,5-dichlorophenol was in the range of 5 - 30 mg/L.

Conclusions:

The 3-hour EC50 of BEPD based on suppression of the respiration of activated sludge microorganisms was 650 mg/L.

Executive summary:

Activated sludge obtained from a sewage treatment plant was exposed in a 3 -hour respiration inhibition test to concentrations of 0, 51.1, 103, 258, 515 and 2575 mg BEPD/L, nominal concentrations were calculated from TOC. The test design included duplicate samples and followed OECD 209 guidelines. The 3 -hour EC50 based on respiration inhibition was 650 mg BEPD/L.