Leucophor 1111X

Short-term toxicity to aquatic invertebrates

Description of key information

EC50 at 48h > 100 mg/l (nominal)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

There are no experimental data available on the Leucophor 1111X, thus a read across approach with the structural analogous substance 01 and the structural analogous 02 has been proposed.

The acute toxicity of the analogous substance 02 to Daphnia magna was investigated under static exposure conditions over a period of 48 h. A screening test with nominal concentrations of 100, 10 and 1 mg/l, respectively, was performed. No chemical analysis of the test media was conducted. For the valuation of the test the nominal content of the test solution was used, assuming the test compound to be stable in water over 48 h.

After 24 h of incubation no significant effects (<10 % of a total of 40 individuals) were observed at all test concentrations and in the blank control, respectively. After 48 h of incubation the following percentage of immobilization of the total of 40 individuals was observed: 100 mg/l (22.5 %).

No significant effects (<10 % of a total of 40 individuals) were observed at 10 and 1 mg/l and in the blank control, respectively. Immobilization at 48 h was slightly increased as compared to the effects after 24 h (Häner, 1999).

The acute toxicity of the analogous substance 01 to Daphnia magna was determined in a 48-hour static test according to the OECD Guideline 202 (2004). A limit test was performed in accordance with the test guidelines, to demonstrate that the test item has no toxic effect on the test organisms up to and including a nominal concentration of 100 mg/l. The analytically determined test item concentration in the test medium at the start and the end of the test was 101 and 110 % of the nominal value, respectively. Consequently, the concentration of the test item was constant during the test period of 48 hours under the conditions of the test, and the reported biological results are based on the nominal concentration of the test item. At the test item concentration of 100 mg/l no immobilized test organisms were observed during the test period of 48 hours (Seyfried, 2006).

All the substances used in a read across approach are Stilbene derivatives Fluorescent Whitening Agents salts. They display similar structural and physicochemical properties: all of them exhibit high degree of dissociation in water and very low octanol/water partition coefficients because to a higher affinity with water phase than the octanol one. They are all very soluble in water, due to the presence of sulphonated groups in the molecules; all of them are non readily biodegradable and are expected to undergo to the same environmental fate.

In both cases the read across approach can be considered as reliable and representative; the differences occurring in the structure formulas (i.e. substituents) are expected to not significantly impact the short-term toxicity to aquatic invertebrates.

Further details about the justification for read across approach are given in the report attached to the Section 13 of this dossier.