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
Test material form:
other: Liquid at room temperature.
Details on test material:
As per IUCLID5 Sections 1.1. 1.2. and 4.1.

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
yes
Details on test solutions:
The test substance was directly weighed into the Biological Oxygen Demand (BOD) test vessels. The test substance was added to 234 mL of deionized water in a quantity appropriate for the desired concentrations. Sixteen mL of synthetic sewage feed and 250 mL of microbial inoculum (activated sludge) were added to each test bottle.

Test organisms

Test organisms (species):
activated sludge of a predominantly domestic sewage
Details on inoculum:
A sample of activated sludge was obtained from the Brazos River Authority in Sugar Land, TX and aerated during transport and storage. The temperature of the sludge sample was 22-24° C and the pH was 7.7-7.9. Dissolved oxygen content was 2.8 mf/L. The sludge was washed three times, with a settling time of 2O minutes between each wash.

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:
22-24° C
pH:
7.7-7.9
Dissolved oxygen:
2.8 mg/L
Salinity:
2 ppt
Nominal and measured concentrations:
75, 150, 300, 600, and 1200 mg/L nominal.
Details on test conditions:
All test procedures took place in thoroughly cleansed 300 mL BOD bottles. The test substance was added to 234 mL of deionized water in a quantity appropriate for the desired concentrations. Sixteen mL of synthetic sewage feed and 250 mL of microbial inoculum (activated sludge) were added to each test bottle. There were five BOD bottles set up for each treatment condition. The control, test substance, and reference sample solutions were measured for dissolved oxygen content independently in series such that each bottle was measured immediately after the expiration of the three hour contact time.


Reference substance (positive control):
yes
Remarks:
3,5-dichlorophenol at 5, 10. 20 and 40 mg/L.

Results and discussion

Effect concentrations
Duration:
3 h
Dose descriptor:
EC50
Effect conc.:
ca. 491.3 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
inhibition of total respiration
Remarks:
respiration rate
Remarks on result:
other: 356.6-595.6 95% Confidence Limits.
Details on results:
The test substance dose level of 300 mg/L had a relative percent inhibition of 22.6% and is considered the NOEC value. At a concentration of 600 mg/L test substance the percent inhibtion was 60.1%. At the high concentration of 1200 mg/L test substance the percent inhibitiomn was 72.9%.
Results with reference substance (positive control):
At a concentration of 40 mg/L the positive control 3,5-dichlorophenol induced a relative percent inhibition of 84.7%.
Reported statistics and error estimates:
The 3 hr EC50 95% confidence Limits were for the test substance were 356.6-595.6 mg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The test substance did have an adverse effect upon the respiration activity of the activated sewage sludge sample. The 3 hr EC50 value was determined to be 491 mg/L. At the concentration of 600 mg/L the relative percent inhibiton of repiration was 60.1 %.
Executive summary:

The test substance, Formaldehyde, polymer with 1,3 -benzenedimethanamine and phenol was accessed for inhibition of activated sludge respiration in an O.E.C.D. test guideline no. 209 study. The test substance did have an adverse effect upon the respiration activity of the activated sewage sludge sample. The 3 hr EC50 value was determined to be 491 mg/L. At the concentration of 600 mg/L the relative percent inhibiton of repiration was 60.1 %.