L-Carnitine-L-Tartrate

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jan to Feb 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, performed in conformity with GLP-principles

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Identity: LZ 1780
- Chemical name: L-Carnitine L-tartrate
- Lot number: 21205
- Expiry date: 09 December 2007
- Appearance: White crystalline powder
- Storage conditions: Room temperature
- Date received: 4 January 2006

Sampling and analysis

Details on sampling:

The test concentration was measured using a LC-MS/MS method of analysis. At the start of the definitive test, four samples (20 ml) were taken from flasks containing the freshly-prepared control and test medium; after 72 hours, the contents of the replicate flasks for each group were pooled and further samples taken for analysis. Additional samples were also taken from a flask containing LZ 1780 at 100 mg/l but with no algal cells, in order to obtain information on the extent of adsorption/absorption of the test substance by the algal cells. On each occasion, the samples were stored frozen for up to six days before two samples from each batch were provided for analysis.

Test solutions

Vehicle:

no

Details on test solutions:

Identity and concentration of auxiliary solvent for dispersal: The test substance was dispersed in algal nutrient medium. See also "details on analytical methods".

Test organisms

Test organisms (species):

Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Details on test organisms:

Axenic, uni-cellular, liquid slope cultures of algae were used. The liquid slope cultures were stored in an illuminated refrigerator. Sterile algal nutrient
medium (Appendix 2) was inoculated with cells aseptically removed from the slope culture; these primary liquid cultures (100 ml) were incubated for approximately three days in an orbital incubator under continuous illumination at nominal temperatures in the range 21 to 25°C. Subsequently, appropriate volumes of these primary cultures were aseptically transferred to fresh sterile algal nutrient medium to prepare secondary liquid cultures; these cultures were incubated, as stated above, for a further three days to provide an inoculum in the log phase of growth, characterised by a cell density of 2.45 x 106 cells/ml.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Post exposure observation period:

Cell numbers were counted daily to monitor growth. The test results are expressed in terms of the area under the growth curve and growth rate.

Test conditions

Hardness:

Not indicated

Test temperature:

The cultures were incubated in an orbital incubator under continuous illumination at temperatures ranging from 22.7 and 23.1°C.

pH:

The pH values were within the range 6.98 to 9.01.

Dissolved oxygen:

Not indicated

Salinity:

Freshwater used.

Nominal and measured concentrations:

Algal cultures, with an initial cell density of 1 x 104/ml, were exposed to LZ 1780 dispersed in algal nutrient medium at a nominal concentration of 100 mg/l. The mean measured level of LZ 1780 in samples of the test cultures taken at the start and end of the test was 107 mg/l.

Details on test conditions:

Environmental parameters remained within acceptable limits throughout the study.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 107 mg/L

Basis for effect:

biomass

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 107 mg/L

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

107 mg/L

Basis for effect:

growth rate

Effect concentrations 4

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

107 mg/L

Basis for effect:

biomass

Details on results:

After 72 hours, no significant inhibition of algal growth was observed.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The acute EC50 to Green Algae was determined to be > 107 mg/l (mean measured concentration). Based on these results, the test item does not have to be classified and has no obligatory labelling requirement according to the European CLP-Regulations (GHS).

Executive summary:

The test item was tested for acute toxicity to Green algae (Pseudokirchneriella subcapitata), according to OECD-Guideline No. 201, EU-Testing Method C.3 and in conformity with GLP-principles. The study was performed from January - February 2006

The acute EC50 to Green Algae was determined to be > 107 mg/l (mean measured concentration). Based on these results, the test item does not have to be classified and has no obligatory labelling requirement according to the European CLP-Regulations (GHS).