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Ecotoxicological information

Toxicity to microorganisms

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Reference
Endpoint:
activated sludge nitrification inhibition testing
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Data is from Peer reviewed journal
Justification for type of information:
Data is from Peer reviewed journal
Reference:
Composition 0
Qualifier:
according to
Guideline:
other: As mention below
Version / remarks:
No data
Principles of method if other than guideline:
Toxicity of menthone on the microorganisms Pseudomonas citronellolis DSM 50332 was studied for 21 days.
GLP compliance:
not specified
Test material information:
Composition 1
Specific details on test material used for the study:
- Name of test material (IUPAC name): (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one- Common name: Menthone - Molecular formula: C10H18O- Molecular weight: 154.2512 g/mol- Smiles notation: C1([C@@H](CC[C@@H](C1)C)C(C)C)=O- InChl: 1S/C10H18O/c1-7(2)9-5-4-8(3)6-10(9)11/h7-9H,4-6H2,1-3H3- Substance type: Organic- Physical state: Liquid
Analytical monitoring:
yes
Details on sampling:
No data available
Vehicle:
yes
Test organisms (species):
other: Pseudomonas citronellolis DSM 50332
Details on inoculum:
- Laboratory culture: Pseudomonas citronellolis DSM 50332 was obtained from the Deutsche Sammlung von Mikroorganismen, Braunschweig, Germany. - Name and location of sewage treatment plant where inoculum was collected: Deutsche Sammlung von Mikroorganismen, Braunschweig, Germany.- Method of cultivation: no data - Preparation of inoculum for exposure: Pure cultures were isolated anaerobically on agar bottle plates in which the substrate was provided by diffusion from a reservoir through the gas phase to the agar surface (10, 19). During all manipulations, the bottles containing the agar were flushed with N2-CO2 (90:10, vol/vol) by using a Hungate syringe. A 20-ml portion of liquid anoxic medium containing 1.5% washed agar was prepared with chelated trace elements instead of non-chelated trace elements (20) and with 50 mM carbonate instead of the phosphate-carbonate buffer above, dispensed into a 100-ml bottle, and solidified quickly by placing the bottle on a plastic bag filled with ice. After inoculation, the agar bottles were inverted, and 75 ml of monoterpene in 3 ml of HMN was added to each bottle. During incubation, the bottles were kept horizontal with the agar aloft. Direct contact between the organic phase and the agar was avoided- Pretreatment: no data- Initial biomass concentration: no data
Test type:
other: Agar diffusion method.
Water media type:
freshwater
Limit test:
no
Total exposure duration:
21 d
Remarks on exposure duration:
Test conducted for 10 days to 21 days.
Post exposure observation period:
No data available
Hardness:
No data
Test temperature:
mesophilic temperature
pH:
7
Dissolved oxygen:
No data
Salinity:
No data
Conductivity:
No data
Nominal and measured concentrations:
Nominal
Details on test conditions:
- Test vessel: Glass bottels- Material, size, headspace, fill volume: 0.5 liter of glass bottles that contained 400 ml of medium, 4 ml of HMN, and 200 ml of liquid substrate- Biomass loading rate: 0.5-liter bottles that contained 400 ml of medium, 4 ml of HMN, and 200 ml of liquid substrate or 200 mg of solid substrate under an N2-CO2 (90:10, vol/vol). A 100-ml portion of the water-mud mixture from the ditch was inoculated into each bottle together with 350 ml of medium, 8 ml of HMN, and 400 ml or 400 mg of substrate. - Photoperiod: performed in dark
Reference substance (positive control):
no
Remarks:
other: Pasteurized samples and inoculated preparations without nitrate or monoterpene were used as controls.
Key result
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
308 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
inhibition of anaerobic gas production
Remarks on result:
other: No inhibition was observed
Details on results:
No data available
Results with reference substance (positive control):
No data available
Reported statistics and error estimates:
No data available
Validity criteria fulfilled:
not specified
Conclusions:
On the basis of no growth inhibition of microorganisms Pseudomonas citronellolis due to the menthone for 10 days to 3 weeks, the NOEC was 308 mg/l (2mM)
Executive summary:

Toxicity of menthone on the growth of microorganisms Pseudomonas citronellol is DSM 50332 for 21 days. Analytical grade samples were used for the test. Test performed in 0.5 liter of agar bottle plates by using the pure culture of microorganism providing proper temperature and PH. Culture were inoculated in dark having the mesophilic temperature. Growth inhibition of Pseudomonas citronellolis was observed at 2m M of concentration of menthone for minimum 10 days to 3 weeks. Analytical grade samples were used for the test. Thus after the exposure with chemical no inhibition was observed. On the basis of no growth inhibition of microorganisms Pseudomonas citronellolis due to the menthone for 10 days to 3 weeks, the NOEC was 308 mg/l (2mM).

Description of key information

Toxicity of menthone on the growth of microorganismsPseudomonas citronellol isDSM 50332 for 21 days. Analytical grade samples were used for the test. Test performed in 0.5 liter of agar bottle plates by using the pure culture of microorganism providing proper temperature and PH. Culture were inoculated in dark having the mesophilic temperature. Growth inhibition of Pseudomonas citronellolis was observed at 2m M of concentration of menthone for minimum 10 days to 3 weeks. Analytical grade samples were used for the test. Thus after the exposure with chemical no inhibition was observed. On the basis of no growth inhibition of microorganisms Pseudomonas citronellolis due to the menthone for 10 days to 3 weeks, the NOEC was 308 mg/l (2mM).

Key value for chemical safety assessment

EC10, LC10 or NOEC for microorganisms:
308 mg/L

Additional information

Toxicity of menthone on the growth of microorganisms Pseudomonas citronellol is DSM 50332 for 21 days. Analytical grade samples were used for the test. Test performed in 0.5 liter of agar bottle plates by using the pure culture of microorganism providing proper temperature and PH. Culture were inoculated in dark having the mesophilic temperature. Growth inhibition of Pseudomonas citronelloliswas observed at 2m M of concentration of menthone for minimum 10 days to 3 weeks. Analytical grade samples were used for the test. Thus after the exposure with chemical no inhibition was observed. On the basis of no growth inhibition of microorganisms Pseudomonas citronellolis due to the menthone for 10 days to 3 weeks, the NOEC was 308 mg/l (2mM).