Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Study period:
2000-2009
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Studies referred to are performed according to Good Laboratory Practice (GLP) and followed the OECD test guidelines 202, 201 and 203, respectively.

Data source

Reference
Reference Type:
other company data
Title:
Unnamed
Year:
2009
Report Date:
2009

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
None
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
None

Sampling and analysis

Details on sampling:
None

Test solutions

Details on test solutions:
According to guideline as applicable.

Test organisms

Test organisms (species):
other: According to guideline as applicable.
Details on test organisms:
According to guideline as applicable.

Study design

Test type:
other: According to guideline as applicable.
Water media type:
freshwater
Limit test:
yes
Remarks on exposure duration:
According to guideline as applicable.
Post exposure observation period:
According to guideline as applicable.

Test conditions

Hardness:
250 mg CaCO3
Test temperature:
20-24
pH:
7-9
Dissolved oxygen:
According to guideline as applicable.
Salinity:
According to guideline as applicable.
Nominal and measured concentrations:
Nominal 100 mg/L
Details on test conditions:
According to guideline as applicable.

Results and discussion

Effect concentrations
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
CC-5-V belongs to the group of LCs as described. The physicochemical and aquatic toxicity data obtained for CC-5-V are similar to the values measured for all the other LC compounds. Using the read-across approach as described in REACh allows a prediction of the EC50 value for algae growth inhibition to be larger than 100 mg/L nominal test item concentration which is larger than the water solubility limit.
Executive summary:

Liquid Crystals (LCs) are compounds which have a common chemical structure consisting of a core structure, terminal (or lateral) substituents and an alkyl or alkenyl side chain. In general, LCs are chemically stable, non-reactive, non-polar and poorly water soluble (<<1 mg/L).

Approximately 50 liquid crystalline compounds (LC) have been tested in short term aquatic toxicity studies with algae, daphnia or fish. The tested compounds comprise the commercially most important as well as structurally diverse liquid crystal compound classes. Due to their low water solubility, the concentrations of the LCs in aquatic toxicity studies are generally extremely low (<< 1 mg/L).

None of the different LC compounds caused any adverse effect on aquatic organisms (fish, daphnia and algae) up to the limit of water solubility. The EC50 values exceed nominal test substance concentrations of 100 mg/L.

These data clearly demonstrate the absence of any toxicity of LCs to aquatic organisms in short term tests up to the limit of water solubility and that liquid crystal compounds show similar ecotoxicological properties (Simon-Hettich, 2000; Simon-Hettich, 2009). This has also been confirmed by the German Federal Environmental Agency (UBA) in an official statement (UBA, 2000).

CC-5 -V belongs to the group of LCs as described. The physicochemical and aquatic toxicity data obtained for CC-5 -V are similar to the values measured for all the other LC compounds. Using the read-across approach as described in REACh allows a prediction of the EC50 value for algae growth inhibition to be larger than 100 mg/L nominal test item concentration which is larger than the water solubility limit.

References:

Simon-Hettich B, Becker W, Takeuchi H, Saito H, Ohnishi H, Takatsu H, Naemura S, Kobayashi K (2000) Ecotoxicological Properties of Liquid Crystal Compounds. Proceedings of the seventh International Display Workshops, November 29-December 1, 2000, Kobe, Japan

 

Simon-Hettich B (2009) Compilation of aquatic toxicity data for Liquid Crystal compounds. Merck KGaA, unpublished report

UBA (2000) Liquid Crystals in Liquid Crystal Displays Statement of the German Federal Environmental Agency Concerning the Ecotoxicology of Liquid Crystals in Liquid Crystal Displays. Status: August 2000.