ALFERROCK

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Duration:

3 wk

Dose descriptor:

LC50

Effect conc.:

>= 1 400 µg/L

Nominal / measured:

nominal

Conc. based on:

element

Basis for effect:

mortality

Duration:

3 wk

Dose descriptor:

EC50

Effect conc.:

>= 620 µg/L

Nominal / measured:

nominal

Conc. based on:

element

Basis for effect:

reproduction

Duration:

3 wk

Dose descriptor:

LOEC

Effect conc.:

>= 620 µg/L

Nominal / measured:

nominal

Conc. based on:

element

Basis for effect:

other: body weight, total protein, GOT activity

Key result

Duration:

3 wk

Dose descriptor:

other: EC16

Effect conc.:

>= 320 µg/L

Nominal / measured:

meas. (initial)

Conc. based on:

element

Basis for effect:

reproduction

Remarks on result:

other: The 16 % reproductive-impairment concentration is given since it represented a minimal reproducible value below which the variability in reproduction could not be detected from controls. Therefore considered to be equivalent to EC10.

Details on results:

No data

Reported statistics and error estimates:

Evaluation of concentration-response curve by the method of Litchfield and Wilcoxon (1949).
For reproductive both the 50 and 16 % reproduction-impairment concentrations are given. The 16 % reproductive-impairment concentration is given since it represented a minimal reproducible value below which the variability in reproduction could not be detected from controls.

The test revelaed that at concentrations >= 620 µg/L the weight per animal was reduced by 38 %, protein content was increased by 3 %, and GOT activity was reduced by 13 % compared to the control group.

Validity criteria fulfilled:

not applicable

Remarks:

non-guideline study, but scientifically solid result published in peer-reviewed article

Conclusions:

Long-term (3 weeks) toxicity (LC50) of aluminium ions to Daphnia magna was determined to be ca. 1.4 mg/L, and EC16 (reproductive impairment, considered to be equivalent to the EC10) was determined to be ca. 320 µg/L.

Executive summary:

The 21-day-chronic toxicity of aluminium to Daphnia magna was studied under static conditions. Daphnids were exposed to control and test chemical at nominal concentrations not reported in detail. The 21-day LC50 based on mortality effect was 1400 µg/L. The 21-day EC10 based on sublethal effects was 320 µg/L. The sublethal effects included were impairment of reproduction, weight decrease, effect on protein content, effect on glutamic oxalacetic transaminase (GOT). Production of offspring in the treated groups indicated that aluminium had an effect on the reproduction at concentrations greater than 320 µg/L. The most sensitive end point was reproduction.

This study is classified as acceptable and satisfies the guideline requirements for a chronic toxicity study with freshwater invertebrates.

 

Results synopsis

Test organism age: 12 ± 12 h at test initiation

Test type: Static

EC10: 320 µg/L (in fact EC16, which provided the lowest reproducible value distinguishable from the controls, thus equivalent to EC10)

Endpoint effected: Reproduction

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Description of key information

The toxicity of "Neutralisation and reduction products of bauxite residue from refinement process" to aquatic invertebrates is based on the released aluminium ions in the transformation/dissolution test. The 21-d EC10 of 320 µg Al/L for reproduction in Daphnia magna is forwarded to the hazard assessment as the relevant endpoint.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC10

Effect concentration:

320 µg/L

Additional information

Toxicity of "Neutralisation and reduction products of bauxite residue from refinement process" to aquatic invertebrates can be elicited by aluminium ions released from the material during dissolution. Studies investigating the toxicity of Aluminium to invertebrates were retrieved from the public domain. The 21-day EC16 (minimal reproducible value, thus equivalent to EC10) of aluminium ions in Daphnia magna was determined to be 320 µg/L (Biesinger and Christensen, 1972).