Aluminum zirconium chloride hydroxide

Short-term toxicity to aquatic invertebrates

Description of key information

Aluminum zirconium chloride hydroxide is an inorganic substance which will rapidly dissociate into aluminum, zirconium, chloride and hydroxide ions upon dissolution in the environment. However, zirconium ions will not remain as such in solution, and the environmental toxicity (if any) will not be driven by zirconium. Therefore, full read-across to other aluminum substances considering a typical aluminum content of ca. 19.4% is justified. The reliable EC50-48h value of 0.33 mg/L dissolved Al derived in a study with Daphnia magna is recalculated and results in an EC50 of 1.701 mg/L aluminum zirconium chloride hydroxide.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1.701 mg/L

Additional information

Aluminum zirconium chloride hydroxide is an inorganic substance which will rapidly dissociate into aluminum, zirconium, chloride and hydroxide ions upon dissolution in the environment. However, zirconium ions will not remain as such in solution. Thus, regarding the environmental fate and toxicity of Aluminum zirconium chloride hydroxide, it can be assumed that environmental fate and toxicity (if any) will not be driven by zirconium. Therefore, full read-across to other aluminum substances considering a typical aluminum content of ca. 19.4% isjustified.

Two short-term studies of aluminum sulphate toxicity to Daphnia magna are available. One test was static without pH adjustment. In this test an EC50 was found of 0.33 mg/l (dissolved Al) at a pH of approximately 6.5 -7.5. The second test was semi-static with pH adjustment. The test substance concentrations were in a range of 10 to 160 mg/l (nominal), this resulted in dissolved aluminum concentrations of 0.107 to 0.176 mg/l. The pH was between 7.5 and 8.0. No effects were found in this test, therefore, EC50 is greater than 0.176 mg/l (dissolved Al), which was the maximum soluble concentration under the test conditions.

Further two short-term studies with Daphnia magna are available for dialuminum chloride pentahydroxide. Both were static at a neutral pH between 7.0 and 7.8. The first study was performed as a WAF; once filtered and once decanted. In both cases a loading of 200 mg/l (nominal) did not cause any effect and the EC50 is greater than 200 mg/l (nominal). No dissolved aluminum was measured. The second study was performed as a limit test at 100 mg/l (nominal). Measured dissolved aluminum concentration was 0.15 mg/l. No effects were found, therefore EC50 is greater than 0.15 mg/l (dissolved Al.).

Two additional short-term studies with aluminum chloride, basic are available for Daphnia magna. One test was static without pH adjustment. In this test an EC50 was found between 0.214 and 1.26 mg/l (dissolved Al) at a pH of approximately 5.1 -8.0. The second test was semi-static with pH adjustment. The pH was between 7.4 and 7.9. The test substance concentrations were in a range of 10 to 160 mg/l (nominal). All measured dissolved Al concentrations were below detection limit after the background concentration present in the control was subtracted. A clear dose-response curve was found when looking at the nominal concentrations, but as the dissolved aluminum concentrations could not be determined, it cannot be stated what the EC50 concentration is exactly. The background concentration was 0.240 mg/l (dissolved Al) therefore, EC50 is greater than 0.240 mg/l (dissolved Al).