Registration Dossier

Administrative data

Endpoint:
activated sludge respiration inhibition testing
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to the O.E.C.D. test guideline 209 with GLP compliance.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2012
Report Date:
2012

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
As per IUCLID Sections 1.1. 1.2. and 4.1.

Sampling and analysis

Analytical monitoring:
no

Test solutions

Details on test solutions:
The test solution was prepared by the direct addition of the test substance to 300 ml glass BOD bottles followed by the addition of distilled water, synthetic sewage feed and activated sludge resulting in a final nominal concentration of approximately 1000 mg/L.

Test organisms

Test organisms (species):
activated sludge of a predominantly domestic sewage
Details on inoculum:
The activated sludge was acquired form the Brazos River Sewer Authority, Sugar Land, Texas and was maintained with aereation. The sludge sample had the following physicalchemical characteristics: Salinity 0.32 ppt; Residual chlorine, 0.12 mg/L; Temperature, 22 C; pH 7.2; Dissolved oxygen, 1.5 mg/L; conductivity, 1046 umhos. The sludge was washed three times with settling before use.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
3 h
Post exposure observation period:
None

Test conditions

Hardness:
No data
Test temperature:
22 C
pH:
7.2
Dissolved oxygen:
1.5 mg/L
Salinity:
0.32 ppt
Nominal and measured concentrations:
10, 100, 1000 mg/L nominal.
Details on test conditions:
Test substance and controls were incubated with the avtivated slidge in a synthetic sewage feed medium for three hours. The exposures were conducted in 300 ml glass BOB bottles with aereation. Following the three hours of contact time. the BOD bottles were sampled for dissolved oxygen content
Reference substance (positive control):
yes
Remarks:
3,5-Dichlorophenol

Results and discussion

Effect concentrations
Duration:
3 h
Dose descriptor:
EC50
Effect conc.:
> 1 000 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
inhibition of total respiration
Remarks:
respiration rate
Details on results:
The NOEC was > 1000 mg/L.
Results with reference substance (positive control):
EC50 3,5-Dichlorophenol = 14.8 mg/L +/- 0.1 mg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The EC50 of the test substance for activated sludge was > 1000 mg/L and the NOEC was > 1000 mg/L. Therefore, the test substance is not anticipated to inhibit the activity of waste water treatment plants.
Executive summary:

The EC50 of the test substance, 4,4'-Isopropylidenedicyclohexanol, oligomeric reaction products with 1-chloro-2,3-epoxypropane in an O.E.C.D. 209 study for activated sludge was > 1000 mg/L. Also, the NOEC value was > 1000 mg/L. Therefore, the test substance is not anticipated to inhibit the activity of waste water treatment plants.