Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Lithium hydroxide monohydrate was tested for toxicity to algae in an 72 h static test according to EU Guideline C.3 and OECD Guideline 201. The results showed an EC50 value of 153.44 mg/L based on growth rate (equivalent to 87.57 mg/L referred to  lithium hydroxide anhydrous). The NOEC based on growth rate and biomass for lithium hydroxide monohydrate was 10 mg/L. The NOEC calculated for lithium hydroxide anhydrous was 5.71 mg/L.

Key value for chemical safety assessment

EC50 for freshwater algae:
87.57 mg/L
EC10 or NOEC for freshwater algae:
5.71 mg/L

Additional information

The influence of the test item lithium hydroxide monohydrate on the growth of Pseudokirchneriella subcapitata was investigated in a 72 h static test according to EU method C.3 and OECD Guideline No. 201 in 2010.

The test item had a statistically significant inhibitory effect on the growth based on the average specific growth rate, yield and areas under the curves of Pseudokirchneriella subcapitata after the exposure period of 72 hours in the concentration range of 20 - 160 mg/L test item/L (Bonferroni t-Test, alpha=0.05). The test concentration of 20 mg/L was determined as the 72-hour LOEC. The results showed an EC50 value of 41.62 mg/L based on biomass and 153.44 mg/L based on growth rate (equivalent to 23.75 mg/L resp. 87.57 mg/L referred to lithium hydroxide anhydrous). The NOEC based on growth rate for lithium hydroxide monohydrate was 10 mg/L. The NOEC calculated for lithium hydroxide anhydrous was 5.71 mg/L.

Another study of 2004 performed with lithium hydroxide anhydrous was disregarded as lithium hydroxide monohydrate is more representative for lithium hydroxide in water due to strong hygroscopic character of the substance (i.e. lithium covered by hydrate mantle).