1-Propanaminium, 3-amino-N-(carboxymethyl)-N,N-dimethyl-, N-C8-10 (even numbered) acyl derivs., hydroxides, inner salts

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms, other

Remarks:

toxicity control from biodegradation in water screening test is used to derive effect concentration

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2004-12-02 to 2004-12-31

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test) (adopted July 17, 1992)

Deviations:

no

Principles of method if other than guideline:

From biodegradation in water: screening test, toxicity control is used to derive effect concentration

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Municipal sewage treatment plant, D-31137 Hildesheim
- Pretreatment: The activated sludge was maintained in an aerobic condition by aeration for four hours and then homogenized with a mixer. The sludge was filtered and the filtrate (30 mL) was subsequently used to initiate inoculation.
- Concentration of sludge: 1E07-1E08 CFU/L in inoculum; 1E05-1E06 CFU/L in test vessels

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

28 d

Test temperature:

20 - 24°C

pH:

7.56 - 7.59 (test item), 7.51 - 7.59 (control), 7.86 (functional control), 7.83 (toxicity control)

Nominal and measured concentrations:

45 mg/L (11.8 mg C/L), nominal

Details on test conditions:

TEST CONDITIONS
- Composition of medium: Mineral nutrient solution acc. to OECD 301 B/CO2 Evolution Test
- Additional substrate: no
- Test temperature: 20 - 24°C, continuously stirred
- pH: 7.56 - 7.59 (test item), 7.51 - 7.59 (control), 7.86 (functional control), 7.83 (toxicity control)
- pH adjusted: no
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: 5000 mL, brown glass; fill volume 3000 mL
- Number of culture flasks/concentration: dupilcate (test item)
- Method used to create aerobic conditions: The vessels were connected to the system for the production of CO2 free air and aerated for 24 h.
- Details of trap for CO2 and volatile organics if used: The CO2 adsorption vessels were connected to the air outlets of the incubation vessels via a series of 3 gas wash bottles.

SAMPLING
- Sampling frequency: three times a week during the first ten days and thereafter twice weekly + on day 29

CONTROL AND BLANK SYSTEM
- Inoculum blank: Nutrient solution and inoculum, duplicates
- functional control: Sodium acetate, 35 mg/L (10.2 mg C/L), single replicate
- Toxicity control: Sodium acetate, 35 mg/L (10.2 mg C/L) + test item 45 mg/L (11.8 mg C/L), single replicate

Reference substance (positive control):

no

Key result

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

45 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Remarks on result:

other: comparison of procedural and toxicity control

Details on results:

The biodegradation of the item mixture in the toxicity control was found to be 63 % after 14 days of incubation and came to a maximum of 85 % after 28 days. Thus, according to the test guidelines, the test item had no inhibitory effect on activated sludge microorganisms at the tested concentration of 45 mg/L, as the biodegradation in the toxicity control was higher than 35% within 14 days of incubation.

Validity criteria fulfilled:

yes

Conclusions:

The toxicity of C8-10 Alkylamidopropyl betaine to microorganisms was investigated during a ready biodegradation study. The test item had no inhibitory effect on activated sludge microorganisms at the tested concentration of 45 mg/L.

Executive summary:

The toxicity of C8-10 Alkylamidopropyl betaine (35% a.i.) to microorganisms was investigated during a ready biodegradation study (CO2 Evolution Test) according to OECD guideline 301 B (1992) over a period of 28 days and using an inoculum obtained from activated sludge from a predominantly domestic sewage treatment plant.

Inoculum blank, procedural/functional control with the reference substance Sodium acetate and a toxicity control with 45 mg/L test item and 35 mg/L reference item Sodium acetate were performed.

The reference item degraded normally (68% within 14 days). By the end of the test, the reference item was degraded by 82%.

The biodegradation of the item mixture in the toxicity control was found to be 63% after 14 days of incubation. Thus, according to the test guidelines, the test item had no inhibitory effect on activated sludge microorganisms at the tested concentration of 45 mg/L, as the biodegradation in the toxicity control was higher than 35% within 14 days of incubation.

Description of key information

14 d NOEC > 45 mg a.i./L, OECD TG 301 B, GLP, RL1

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:

45 mg/L

Additional information

The toxicity of C8-10 Alkylamidopropyl betaine (35% a.i.) to microorganisms was investigated during a ready biodegradation study (CO2 Evolution Test) according to OECD guideline 301 B (1992) over a period of 28 days and using an inoculum obtained from activated sludge from a predominantly domestic sewage treatment plant.

Inoculum blank, procedural/functional control with the reference substance Sodium acetate and a toxicity control with 45 mg/L test item and 35 mg/L reference item Sodium acetate were performed.

The reference item degraded normally (68% within 14 days). By the end of the test, the reference item was degraded by 82%.

The biodegradation of the item mixture in the toxicity control was found to be 63% after 14 days of incubation. Thus, according to the test guidelines, the test item had no inhibitory effect on activated sludge microorganisms at the tested concentration of 45 mg/L, as the biodegradation in the toxicity control was higher than 35% within 14 days of incubation.