Aluminium nitride

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

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:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 0.57 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

dissolved

Remarks:

aluminium

Basis for effect:

mortality (fish)

Remarks on result:

other: hardness: 23.2 mg/L CaCO3; result from filterable aluminum fraction (0.4 µm polycarbonate filter)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 0.61 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

dissolved

Remarks:

aluminium

Basis for effect:

mortality (fish)

Remarks on result:

other: hardness: 35.0 mg/L CaCO3; result from filterable aluminum fraction (0.4 µm polycarbonate filter)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 0.73 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

dissolved

Remarks:

aluminium

Basis for effect:

mortality (fish)

Remarks on result:

other: hardness: 83.6 mg/L CaCO3; result from filterable aluminum fraction (0.4 µm polycarbonate filter)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 0.67 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

dissolved

Remarks:

aluminium

Basis for effect:

mortality (fish)

Remarks on result:

other: hardness: 115.8 mg/L CaCO3; result from filterable aluminum fraction (0.4 µm polycarbonate filter)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

6.17 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: total aluminium

Basis for effect:

mortality (fish)

Remarks on result:

other: hardness: 23.2 mg/L CaCO3

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

6.17 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: total aluminium

Basis for effect:

mortality (fish)

Remarks on result:

other: hardness: 35 mg/L CaCO3

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

7.67 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: total aluminium

Basis for effect:

mortality (fish)

Remarks on result:

other: hardness: 83.6 mg/L CaCO3

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

6.93 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: total aluminium

Basis for effect:

mortality (fish)

Remarks on result:

other: hardness: 115.8 mg/L CaCO3

Details on results:

- Behavioural abnormalities: No data
- Observations on body length and weight: No data
- Other biological observations: No data
- Mortality of control: 0 %
- Other adverse effects control: No data
- Abnormal responses: No data
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: None reported
- Effect concentrations exceeding solubility of substance in test medium: No

Reported statistics and error estimates:

LC50 by the trimmed Spearman-Karber estimator; 95 % confidence intervals.

Sublethal observations / clinical signs:

Test	Average hardness [mg/L CaCO3]	LC50 (95 % CI) based on measured aluminum [mg/L]
		Total	Filterable
Acute Hardness	23.2	6.17 (5.33–7.25)	0.57 (0.51–0.64)
	35.0	6.17 (5.31–7.20)	0.61 (0.51–0.73)
	83.6	7.67 (6.22–9.61)	0.73 (0.65–0.94)
	115.8	6.93 (n.a.)	0.67 (n.a.)

Validity criteria fulfilled:

not applicable

Remarks:

Non-guideline study, but scientifically robust result published in peer-reviewed article.

Conclusions:

Short-term (96 h) toxicity of aluminium to fish (juvenile rainbow trout) was determined. The study revealed LC50 values between 6.17 and 7.67 mg/L total aluminium in dependence of water hardness (0.57-0.67 mg Al/L in filtered samples). Aluminium-induced mortality was higher at weakly alkaline pH (7.95 to 8.58) (attributed to up to 18-fold higher filterable aluminium concentrations) than near-neutral pH (7.14-7.64). The study revealed that the toxicity of aluminium towards fish depends on water hardness and pH. The 96-h LC50 values for total aluminium ranged from 6.17 to 7.67 mg aluminium per liter at average hardness concentrations of 23.2 and 83.6 mg per liter expressed as CaCO3.

Executive summary:

In a 96-h acute toxicity study, rainbow trout (Oncorhynchus mykiss) were exposed to aluminium at measured concentrations of 0 (control), 0.11, 0.18, 0.42, and 1.00 mg/L in filtered samples (0.4 µm filter) under flow-through conditions. The 96-h LC₅₀was 0.57 mg/L in filtered samples and 6.17 mg/L in unfiltered samples. Sublethal effects of aluminium were not reported. Based on the results of this study, aluminium ions would be classified as acutely toxic fish in accordance with the classification system of CLP Regulation.

This toxicity study is classified as acceptable and satisfies the guideline requirement for fish toxicity studies.

Results synopsis

Test organism size/age: 1–3 cm

Test type: Flow-through

LC₅₀: 0.57 mg/L (95 % C.I.: 0.51–0.64 mg/L) as dissolved aluminium (0.4 µm filter)

LC₅₀: 6.17 mg/L (95 % C.I.: 5.33–7.25 mg/L) as total aluminium

Endpoint(s) effected: Mortality

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.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

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:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 584 µg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mortality (fish)

Remarks:

at pH 5.5

Remarks on result:

other: 95% CL = 444-676

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 599 µg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mortality (fish)

Remarks:

at pH 6.5

Remarks on result:

other: 95% CL = 445-772

Details on results:

Other biological observations: At pH 5.5 and 6.5 without aluminium, histomorphological examinations revealed no abnormalities in gill tissue. In aluminium exposure, gill filaments and secondary lamellae were swollen and thickened.
- Other adverse effects control: none

Reported statistics and error estimates:

Effects of pH and toxicants on percent survival and growth of Atlantic salmon were evaluated by analysis of variance using the Statistical Analysis System (SAS Institute Inc. 1985).

Validity criteria fulfilled:

not applicable

Remarks:

Non-guideline study, but scientifically robust result published in peer-reviewed article.

Conclusions:

Atlantic salmon was exposed to aluminum and the resulting LC50 (96 h) values were determined to 587 µg/L (pH 5.5) and to 599 µg/L (pH 6.5).

Executive summary:

In a 96-h acute toxicity study, Atlanic salmon (Salmo salar) were exposed to aluminum at nominal concentrations of 0 (control) 4700 µg/L under static conditions. The 96-h LC₅₀was 599 µg/L. Sublethal effects of aluminium were not reported. Based on the results of this study, aluminium ions would be classified as acutely toxic fish in accordance with the classification system of CLP Regulation.

This toxicity study is classified as acceptable and satisfies the guideline requirement for fish toxicity studies.

Results synopsis

Test organism size/age: Alevins

Test type: Static

LC₅₀: 599 µg/L (95 % C.I.: 445–772 mg/L) as dissolved aluminium

Endpoint(s) effected: Mortality

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.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

supporting 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:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 11.1 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

element

Remarks:

NH3-N

Basis for effect:

mortality (fish)

Remarks on result:

other: 95 % CI = 9.92-12.4

Reported statistics and error estimates:

LC50 values and 95 % confidence intervals were estimated using the trimmed Spearman-Karber method.

Sublethal observations / clinical signs:

The lowest LC50 value among all tests conducted was the following (Appenendix of the publication):

LC50 (96 h) = 11.1 mg/L (95 % CI: 9.92–12.4)

Biometric parameters and test conditions relevant for the fish used in this experiment are quoted in the methods section above.

Furthermore, a selection of less conservative results is presented in the tables below:

Table 2: Acute toxicity of ammonia to rainbow trout in tests at higher temperatures.

Mean fish size		Mean dissolved oxygen(mg/L) (range)	Mean pH (range)	Mean temperature(°C) (range)	96-hour LC50
Weigth (g)	Total length(cm)				NH3-N (mg/L)	NH3 (mg/L)
9.4	9.6	6.6 (5.4 – 7.9)	7.85 (7.82 – 7.88)	16.1 (15.4 – 17.0)	34.2 (31.7 – 36.8)	0.856 (0.794 – 0.923)
11.9	10.1	6.3 (5.8 – 6.8)	7.88 (7.84 – 7.94)	16.7 (15.7 – 17.8)	28.6 (26.3 – 31.2)	0.801 (0.736 – 0.872)
7.1	8.4	7.1 (6.0 – 8.6)	7.91 (7.88 – 7.96)	19.0 (17.9 – 19.6)	25.4 (23.2 – 27.8)	0.897 (0.820 – 0.982)
10.1	9.8	6.2 (5.5 - 7.6)	7.91 (7.88 – 8.02)	19.1 (18.6 – 19.6)	26.4 (24.4 – 28.7)	0.942 (0.868 – 1.02)
8.6	8.9	6.4 (5.9 – 7.3)	7.96 (7.93 – 8.02)	19.2 (18.8 – 19.7)	23.2 (21.2 – 25.4)	0.931 (0.852 – 1.02)

Table 3: Acute toxicity of ammonia to rainbow trout related to NH4Cl as the toxicant source.

Ammonium salt	Mean fish size		Mean pH (range)	Mean temperature(°C) (range)	96-hour LC50 (95 % confidence interval)
	Weigth (g)	Total length(cm)			NH3-N (mg/L)	NH3 (mg/L)
NH4Cl	1.7	5.8	7.86 (7.79 – 7.96)	14.1 (13.3 – 15.2)	34.9 (31.6 – 36.8)	0.772 (0.698 – 0.854)
NH4Cl	1.8	5.7	7.84 (7.82 – 7.91)	13.8 (13.3 – 14.5)	33.1 (30.2 – 36.2)	0.683 (0.628 – 0.730)

Table 4: Acute toxicity of ammonia to rainbow trout in test lasting 12 and 35 days.

Mean fish weigth (g)	No. of fish per tank(cm)	Mean dissolved oxygen, mg/L (range)	Mean pH (range)	Mean temperature(°C) (range)	LC50 (mg NH3 / L) (95 % confidence interval)
					4-day	12-day	35-day
0.71	20	8.2 (7.9 –8.5)	7.81 (7.80 – 7.85)	13.0 (12.6 – 13.5)	Not measured	0.562 (0.520 – 0.607)	0.483 (0.459 – 0.509)
0.76	20	8.2 (7.9 – 8.5)	7.89 (7.85 – 7.90)	12.6 (12.2 – 13.0)	Not measured	Not measured	0.598 (0.546 – 0.654)
2.5	20	8.7 (8.4 – 9.2)	7.85 (7.80 – 7.92)	13.1 (12.4 – 14.3)	0.632 (16.8 – 19.6)	0.490 (0.450 – 0.534)	Not measured
3.3	20	7.3 (6.89 – 8.0)	7.69 (7.60 – 7.85)	13.2 (13.0 – 13.5)	Not measured	Not measured	0.426 (0.410 – 0.441)
3.7	20	6.2 (5.3 – 7.5)	7.69 (7.60 – 7.80)	13.2 (13.0 – 13.5)	Not measured	Not measured	0.322 (0.308 – 0.336)
7.9	20	8.2 (7.7 – 9.2)	7.90 (7.78 – 8.01)	11.9 (11.3 – 12.9)	27.0 (24.8 – 29.4)	0.464 (0.438 – 0.492)	Not measured
9.3	20	6.6 (6.1 – 7.8)	7.9	13	36.7 (32.2 – 41.9)	0.684 (0.626 – 0.733)	Not measured
9.7	20	6.1 (5.7 – 8.0)	7.9	13	39.2 (35.2 – 43.8)	0.262 (0.234 – 0.294)	0.659 (0.599 – 0.725)
513	10	7.6 (6.5 – 8.3)	7.66 (7.60 – 7.72)	9.8 (9.7 – 9.9)	39.2 (35.2 – 43.8)	0.262 (0.234 – 0.294)	Not measured
558	10	6.9 (5.6 – 7.7)	7.64 (7.56 – 7.74)	10.0 (9.9 – 10.1)	39.2 (35.2 – 43.8)	0.312 (0.275 – 0.353)	Not measured

Validity criteria fulfilled:

not applicable

Remarks:

Non-guideline study, but scientifically robust result published in peer-reviewed article.

Conclusions:

A study was performed at various test conditions to determine the toxicity of ammonia to rainbow trout. Relevant parameters, including temperature, dissolved oxygen, pH and ammonia concentration were determined throughout the test.
The tolerance of rainbow trout to ammonia seems to increase as the fish develops through the larval stages, is greatest at the juvenile and yearling stages, and decreases thereafter. Most mortality was observed within the first 96 h. The lowest measured LC50 (96 h) value was 0.636 mg/L free NH3, based on a measurements of the ammonium concentration in solution. The lowest measured LC50 values for the 4-day, 12-day and 35-day experiments are 0.262, 0.262 and 0.322 mg/L NH3.

Executive summary:

In a 96-h acute toxicity study, rainbow trout (Oncorhynchus mykiss, reported as Salmo gairdneri) were exposed to ammonia at measured concentrations (exact values not reported) under flow through conditions. The lowest 96-h LC₅₀ among a series of 71 experiments with varying temperatures, and oxygen concentrations, and ammonia sources, was 11.1 mg/L (as NH₃-N). Sub-lethal effects of were not reported. Based on the results of this study, ammonia would not be classified as acutely toxic to fish in accordance with the EU CLP Regulation.

This toxicity study is classified as acceptable and satisfies the guideline requirement for fish toxicity studies, with some reporting deficiencies that do not compromise the overall quality of the study.

Results synopsis

Test organism size (mean length): 2.4 cm

Test type: Flow-through

LC₅₀: 11.1 mg NH₃/L (95 % C.I.: 9.92–12.4 mg/L)

Endpoint(s) effected: Mortality

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 short-term toxicity (96 h) of aluminium to fresh water fish (juvenile rainbow trout) has been determined to be between 6.17 and 7.67 mg/L aluminium (depending on water hardness). In another study Atlantic salmon was exposed to aluminium and the resulting LC50 (96 h) values were determined to be between 587 µg/L (pH 5.5) and to 599 µg/L (pH 6.5). The toxicity of ammonia, the other significant degradation product of AlN, was studied at various test conditions towards rainbow trout. The lowest measured LC50 value (96 h) was 11.1 mg/L dissolved total ammonia nitrogen (NH3-N).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

6.17 mg/L

Marine water fish

Marine water fish

Dose descriptor:

LC50

Effect concentration:

587 µg/L

Additional information

Three studies have been evaluated to assess the short-term toxicity of aluminium and ammonia, the environmentally relevant degradation products of AlN, to fish. The studies revealed a higher short-term (96 h) toxicity of aluminium to the Atlantic salmon (0.587 -0.599 mg/L, depending on pH) and a lower short-term toxicity to the freshwater fish juvenile rainbow trout (6.17-7.67mg/L, depending on water hardness). The toxicity of ammonia was studied at various test conditions towards rainbow trout (Salmo gairdneri). The lowest measured LC₅₀ (96 h) value was 11.1 mg/L (in terms of total ammonia, i.e. NH₃-N).

A general tendency of increased toxicity of aluminium towards marine fish cannot be claimed because only one species was used for each type of habitat. The toxicity of ammonia to fish was expressed in the study as LC₅₀ values related to dissolved ammonium-nitrogen concentration and related to free ammonia (NH₃). The LC₅₀ value calculated on the basis of unionised ammonia (NH3) was not used as basis for the risk assessment because this would overestimate the toxicity of ammonium in aqueous solution drastically. If ammonia comes in contact with water it will form an equilibrium between the ionised and the unionised form which is highly on the side of the ionised form, slightly depending on temperature and pH. Nevertheless, the amount of ionised ammonium will be much higher compared to the NH3-form. For this reason the environmental risk characterisation will be performed on the basis of the lowest LC₅₀ value identified for aluminium. The contribution of ammonia to the toxicity against fish, which is significantly lower, can be ignored.