1,1'-(ethane-1,2-diyl)bis[pentabromobenzene]

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jan 4, 2008 to Feb 14, 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: study performed using international guidelines and GLPs using the commercial product as test article and published in the literature

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

2008

Reference 2

Reference Type:

publication

Title:

Results of terrestrial and aquatic studies on the brominated flame retardant, decabromodiphenyl ethane, a.k.a. Ethane 1,2 bis(pentabromophenyl)

Author:

Hardy et al.

Year:

2009

Bibliographic source:

SETAC Annual Meeting, Nov 2009, New Orleans, LA

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,1'-(ethane-1,2-diyl)bis[pentabromobenzene]

EC Number:

284-366-9

EC Name:

1,1'-(ethane-1,2-diyl)bis[pentabromobenzene]

Cas Number:

84852-53-9

Molecular formula:

C14H4Br10

IUPAC Name:

1,2,3,4,5-pentabromo-6-[2-(2,3,4,5,6-pentabromophenyl)ethyl]benzene

Details on test material:

The test article was 97.64% DBDPEthane.

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

activated sludge of a predominantly domestic sewage

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

3 h

Post exposure observation period:

no

Test conditions

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Duration:

3 h

Dose descriptor:

NOEC

Effect conc.:

>= 10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

see below

Any other information on results incl. tables

Treatment	Respiration Rate (mg O2/L/h)	Inhibition (%)
Control	32.3, 31.3	---
DBDPEthane (10mg/kg)	33.5	-5.3
Reference Inhibitor (3, 15, 50 mg/kg)	32.4, 18.9, 6.1	-1.9, 40.6, 80.8

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

DBDPEthane did not adversely affect sludge respriation at a dose of 10 mg/L.

Executive summary:

The effect of DBDPEthane on activated sludge microorganisms maintained in an aerobic environment was assessed. The study contained control and reference groups and a treatment vessel. The control replicates were used to determine the background respiration rate of the sludge and were not dosed with the test or reference substance. The reference group was dosed with 3,5 -dichlorophenol, a known inhibitor of respiration, at concentrations of 3, 15 and 50 mg/L. The treatment vessel was dosed with DBDPEthane at a concentration of 10 mg/L. After an exposure period of 3 hr, the respiration rates of the test solutions were measured using a YSI Model 50 B Dissolved Oxyegen Meter. The respiration rates in the two controls were 32.3 and 31.3 mg O2/L/hr. The difference between the two control respriation rates was approximately 3% and was within the 15% difference limit established for the test. The validity of the test was further supporte by the results from the 3,5 -dichlorophenol reference group, which resulted in an EC50 of 19.4 mg/L with 95 % confidence limits of 3 and 50. The EC50 for the reference substance was within the 5 to 30 mg/L range considered acceptable for the test. The % respiration inhibition observed for DBDPEthane at 10 mg/L was -5.3%. Under the conditions of the study, DBDPEthane did not adversely affect sludge respriation.