Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Fatty acids, C16-18, zinc salts:

The toxicity of fatty acids, C16 -18, zinc salts to the freshwater algae (Pseudokirchneriella subcapitata) is estimated with an EL50 > 100 mg/L and an EL10= 3.31 mg/L based on loadings of the applied dissolved fraction.

Since only limited long-term toxicity data are available for fatty acids, C16-18, zinc salts and C16 -18 fatty acids have a low potential for aquatic toxicity, the aquatic hazard assessment of fatty acids, C16-18, zinc salt is based on zinc ions. Please refer to the endpoint summary of the respective assessment entity for further details.

 

Fatty acid anions (C16-18):

Fatty acids as contained in plant and animal tissue are a natural component of aquatic systems, are rapidly degraded and non-bioaccumulative and have of low potential for toxicity to algae.

 

Zinc:

The lowest IC50 amounts to 0.136 mg Zn/L (single value) at neutral/high pH whereas the lowest NOEC is estimated with 0.019 mg Zn/L (geomean of 27 values) - all for Selenastrum capricornutum. Regarding marine algae, NOECs are available for 12 species ranging from 0.0078 to 0.67 mg/L (dissolved concentrations).

 

Key value for chemical safety assessment

Additional information

Fatty acids, C16-18, zinc salts:

Acute freshwater toxicity tests of high quality and relevancy were performed according to OECD 201. Data are available for one species (Pseudokirchneriella subcapitata), the most sensitive freshwater species. The lowest EC50 value is applied as reference value for classification for short-term effects.

Chronic freshwater toxicity tests of high quality and relevancy were performed according to OECD 201. Data are available for one species (Pseudokirchneriella subcapitata), and are the only chronic data available for freshwater organisms relevant for classification. The lowest EC10 value is applied as reference value for classification for long-term effects.

In a growth inhibition test with P. subcapitata exposed to dissolved fractions of fatty acid, C16-18, zinc salts at loadings of 0.01, 0.1, 1, 10 and 100 mg/L in standard test medium over a test period of 72 hours (Wenzel, 2013a), the calculated EL10 value for growth rate was 3.31 mg/L (extrapolated) whereas the EL50 is expected to be > 100 mg/L based on loadings of the applied dissolved fraction.

In addition, a growth inhibition test with P. subcapitata exposed to the dissolved fractions of zinc dilaurate at loadings of 0.01, 0.1, 1 and 10 mg/L in standard test medium over a test period of 72 hours revealed calculated EL50 values for growth rate of 12.87 mg/L (extrapolated) while the EL10 was 3.73 mg/L, based on loadings of the applied dissolved fraction (Wenzel, 2013b). Thus, toxicity data from a structural analogue, i.e. zinc dilaurate - a zinc salt of a shorter-chained fatty acid (C12), support the conclusion that zinc salts of fatty acids with a similar structural analogy, water solubility and zinc content, are not toxic to algae at concentrations below relevant acute and chronic aquatic classification criteria.

Acute or chronic seawater tests were not performed with Fatty acids, C16-18, zinc salts.