Registration Dossier

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
toxicity to microorganisms
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2012-02-23 to 2012-03-22
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study, GLP.
Reason / purpose for cross-reference:
reference to same study
Qualifier:
according to guideline
Guideline:
other: OECD Guideline 310 (Ready Biodegradability - CO2 in Sealed Vessels (Headspace Test), adopted 23 March 2006
Deviations:
no
Principles of method if other than guideline:
Toxicity screening conducted during the OECD 310 - biodegradation test
GLP compliance:
yes (incl. QA statement)
Remarks:
certificate dated 2010-10-20
Analytical monitoring:
yes
Vehicle:
no
Test organisms (species):
activated sludge, domestic
Details on inoculum:
- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Municipal sewage treatment plant, Hildesheim, Germany
- Preparation of inoculum for exposure:
Activated sludge was washed twice with autoclaved tap water. After the second washing the settled sludge was resuspended in mineral salts medium and was maintained in an aerobic condition by aeration for 2-4 hours. Thereafter the sludge was homogenized with a blender. The supernatant was decanted and was maintained in an aerobic condition by aeration with CO2-free air for 6 days. 10 mL/L were used to initiate inoculation.
- Initial cell/biomass concentration: 10E05 - 10E08 CFU/L in the test solution
Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
28 d
Test temperature:
20 - 22°C
pH:
no data
Dissolved oxygen:
no data
Nominal and measured concentrations:
20 mg/L nominal
Details on test conditions:
TEST CONDITIONS
- Composition of medium: mineral salts medium acc. to OECD 310 / 80 mL
- Additional substrate: no
- Test temperature: 20 - 22°C
- pH: no data
- Continuous darkness: low light conditions
- Other: agitation on shaker 150-200 rpm

TEST SYSTEM
- Culturing apparatus: Headspace flasks / 120 mL, headspace-to-liquid-ratio 1:2
- Number of culture flasks/concentration: triplicates (test end 5 replicates)
Measurement of the increase of the inorganic carbon (IC) concentration during the incubation: Sodium hydroxide solution (0.74 mL 7 mol/L solution to 80 mL medium) was injected to each vessel sampled. The vessels were shaken on an overhead shaker (100 rpm) for 1 h at test temperature. Suitable volumes of the liquid phase were analysed.

SAMPLING
- Sampling frequency: day 0, 4, 8, 11, 14, 21, 28

CONTROL AND BLANK SYSTEM
- Inoculum blank: mineral salts medium + inoculum
- Toxicity control: test item in test concentration + 30 mg/L reference item (sodium benzoate)
Reference substance (positive control):
no
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
20 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth inhibition
Details on results:
The 10% level (beginning of biodegradation) was reached after 2 d. The pass level of 60% was reached after 9 d and the biodegradation came to 84% after 28 d.

The biodegradation of the toxicity control reached 83% within 14 d and it came to 89% after 28 d. The biodegradation of the reference item was not inhibited by the test item in the toxicity control. The 95% confidence interval on day 28 was 86 - 93%
Results with reference substance (positive control):
n.a., no positive control

The adaptation phase of the functional control changed after 1 day into the degradation phase (degradation > 10%). The course of the degradation phase was rapid and the pass level of 60% was reached after 3 days. The biodegradation came to 91% after 28 days. The validity criterion degradation > 60% after 14 d is fulfilled. The 95% confidence interval on day 28 was 90 - 93%.

Validity criteria fulfilled:
yes
Conclusions:
The toxicity of 1,4-BDDMA (99.67% a.i.) to microorganisms was investigated during a ready biodegradation study. The test substance was assumed not to inhibit microbial activity at concentrations up to 20 mg/L.
Executive summary:

The toxicity of 1,4 -BDDMA (99.67% a.i.) to microorganisms was investigated during a ready biodegradation study according to OECD guideline 310 (Headspace Test), adopted 23 March 2006, over a period of 28 days and using predominantly domestic non-adapted activated sludge as inoculum.

The biodegradation rate was determined by measurement of carbon dioxide evolution.

Inoculum blank, procedural/functional control with the reference substance Sodium benzoate and toxicity control with reference substance and test substance (20 mg/L test substance) were performed.

The 10% level (beginning of biodegradation) was reached after 2 d. The pass level of 60% was reached after 9 d and the biodegradation came to 84% after 28 d. The biodegradation of the toxicity control reached 83% within 14 d and it came to 89% after 28 d. The biodegradation of the reference item was not inhibited by the test item in the toxicity control. The 95% confidence interval on day 28 was 86 - 93%

Therefore, the test substance was assumed not to inhibit microbial activity at a concentration of 20 mg/L.

NOTE: Any of data in this dataset are disseminated by the European Union on a right-to-know basis and this is not a publication in the same sense as a book or an article in a journal. The right of ownership in any part of this information is reserved by the data owner(s). The use of this information for any other, e.g. commercial purpose is strictly reserved to the data owners and those persons or legal entities having paid the respective access fee for the intended purpose.

Description of key information

The NOEC of 1,4-BDDMA in microorganisms was 20 mg/L (OECD guideline 310; Headspace Test). 

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:
20 mg/L

Additional information

One toxicity screening study conducted during the OECD 310 biodegradation test is available for 1,4-BDDMA, which is considered reliable without restriction (Klimisch score 1). A Bringman-Kühn test with 1,3-BDDMA with not assignable reliability (Klimisch score 4) is used as supporting data.

 

The toxicity of 1,4 -BDDMA (99.67% a.i.) to microorganisms was investigated during a ready biodegradation study according to OECD guideline 310 (Headspace Test), adopted 23 March 2006, over a period of 28 days and using predominantly domestic non-adapted activated sludge as inoculum.

The biodegradation rate was determined by measurement of carbon dioxide evolution.

Inoculum blank, procedural/functional control with the reference substance Sodium benzoate and toxicity control with reference substance and test substance (20 mg/L test substance) were performed.

The 10% level (beginning of biodegradation) was reached after 2 d. The pass level of 60% was reached after 9 d and the biodegradation came to 84% after 28 d. The biodegradation of the toxicity control reached 83% within 14 d and it came to 89% after 28 d. The biodegradation of the reference item was not inhibited by the test item in the toxicity control. The 95% confidence interval on day 28 was 86 - 93%

Therefore, the test substance was assumed not to inhibit microbial activity at a concentration of 20 mg/L.

 

In a 16-h toxicity study conducted according to the Bringmann-Kühn test, cultures of Pseudomonas putida were exposed to 1,3 -BDDMA at a nominal concentration of 50 mL/L (corresponding to 51.2 g/L based on a density of 1.024 g/cm³). The EC10 was reported to be > 51.2 g/L. However, the sample has a lower water solubility. The maximum water solubility is 243 mg/L (for experimental result see Water solubility).