Isopropylamine

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1979

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Pre-guideleine study equivalent to OECD 203. However, without analytical verification of test item concentrations.

Reason / purpose for cross-reference:

reference to other study

Qualifier:

equivalent or similar to guideline

Guideline:

other: DIN 38412 Teil 15

Version / remarks:

June 1982

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

adopted July 1992

Deviations:

yes

Remarks:

without analytical verification of test item concentrations; pH was not neutralized at the beginning of the test

Principles of method if other than guideline:

Bestimmung der Wirkung von Wasserinhaltsstoffen auf Fische, DIN 38412 Teil 15

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

A stock solution was prepared in test water (concentration not specified) and applied into the test basins (after fish had been introduced into test basins beforehand), evenly distributed via glass rod.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Oncorhynchus mykiss (previous name: Salmo gairdneri)
- Length at study initiation: range: 4.9-7.1 cm, mean=6.0 cm, SD=0.54 cm, n=100
- Weight at study initiation: range: 2.0-4.5 g, mean=3.3 g, SD=0.71 g, n=100

ACCLIMATION
- Acclimation period: at least 14 days

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

no

Hardness:

Total: 9.5°d
Carbonate: 6.4°d

Test temperature:

12 +/- 1°C

pH:

7.9 - 8.4 (without test substance)
intermittent increase up to 10.2 due to addition of test substance (no further details given)

Dissolved oxygen:

> 8 mg/L

Salinity:

NaHCO3: 192 mg/L,
CaSO4*2H2O:120 mg/L
MgSO4: 120 mg/L
KCl: 8 mg/L

Conductivity:

< 5 µS/cm

Nominal and measured concentrations:

1st part of experiment: 0, 1, 10, 100 mg/L (nominal)
2nd part of experiment: 0, 16, 25, 40, 63, 80 mg/L (nominal)

Details on test conditions:

Number of fish: 10 per test concentration
TEST SYSTEM
- Test vessel:
- Type: open
- Material, size, headspace, fill volume: Glass, 40 cm x 25 cm x 30 cm filled with 20 L water
- Aeration: by glass capillaries, ca. 150 ml air per minute
- Renewal rate of test solution (frequency/flow rate): static
- No. of organisms per vessel: 5 or 10 in first and second experiment, respectively
- No. of vessels per concentration (replicates): 2 or 1 in first and second experiment, respectively
- No. of vessels per control (replicates): 2 or 1 in first and second experiment, respectively
- Biomass loading rate: ca. 33 g/ 20 L (1.65 g/ L)


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Deionised water
- Total organic carbon: not determined
- Chlorine: Dechlorinated
- Ca/Mg ratio: see above (Salinity)
- Conductivity: no data
- Intervals of water quality measurement: 24h


OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 12h
- Light intensity: ca. 700 Lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality


TEST CONCENTRATIONS
- Spacing factor for test concentrations: ca. 1.6 (second experiment)
- Justification for using less concentrations than requested by guideline:
- Range finding study
- Test concentrations: First Experiment 0, 1, 10, 100 mg/ L (full test)

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

LC100

Effect conc.:

63 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

40 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC0

Effect conc.:

25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

63 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

40 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

EC0

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Sublethal observations / clinical signs:

MORTALITY
No deaths were observed at 25 mg/L.

Test number of animals

concentration                                                 dead/alive [96 h]

=====================================

0 mg/L                                                               0/20

1 mg/L                                                                0/10

10 mg/L                                                              0/10

16 mg/L                                                             0/10

25 mg/L                                                              0/10

40 mg/L                                                              5/10

63 mg/L                                                             10/10

80 mg/L                                                             10/10

100 mg/L                                                           10/10

=====================================

Signs of Intoxication

No toxicity and no symptoms were evident at the concentrations of 1 and 10 mg/L.

At 16 mg/L and higher: dark discoloration, apathy, imbalance, dorsal position at the bottom of the vessel.

Deceased animals showed a wide-opened mouth and swollen gills.

The surviving animals showed no visible abnormalities.
-----------------

Validity criteria fulfilled:

yes

Remarks:

however, no analytical verification of test item concentrations

Conclusions:

LC50 (96 h; Oncorhynchus mykiss; static; nominal) = 40 mg/L, study equivalent or similar to OECD Guideline 203 (Fish, Acute Toxicity Test; adopted in July 1992), RL2. Manifestation of symptoms went in line with significantly elevated pH values (16 mg/L test item concentration and higher), lethality after 48 h was identical to the one observed after 96 h. This is indicative for pH induced toxicity (pH 10.2 reported for 100 mg/L).

Executive summary:

Toxicity of isopropylamine to freshwater fish was assessed in a pre-guideleine study equivalent to OECD 203 (adopted in July 1992), with acceptable restrictions (RL2). The tested freshwater species was Rainbow trout (Oncorhynchus mykiss). Per concentration 10 fish were tested. The following 8 test item concentrations (nominal) were applied: 1, 10, 16, 25, 40, 63, 80 and 100 mg/L. The concentrations 1, 10 and 100 mg/L were applied in the first and 16, 25, 40, 63 and 80 mg/L in the second part of the experiment. No chemical analysis of the test item concentrations was performed. However, based on the very high water solubility of the compound (miscible in a 1 : 1 ratio mixture (w/w) with water (at 20°C)), the very low adsorption potential (read across with n-butylamine (source): experimentally determined Koc from batch-equilibrium test: approx. 43.2 L/kg) and being not volatile (fully ionized at environmental pH) it may be assumed with high confidence that the test item was stable during the test. While not all validity criteria specified in OECD 203 could be assessed directly, taking all information given into account, it is highly probable that all validity criteria were met.

Results:

At the lower test item concentrations applied (1, 10, 16, 25 mg/L), no mortality was observed during the 96 h of the test. At the concentration 40 mg/L, mortality was 50% and at 63, 80 and 100 mg/L, mortality was 100%. The LC50 (96 h) was identified as 40 mg/L.

Manifestation of symptoms went in line with significantly elevated pH values (16 mg/L test item concentration and higher), lethality after 48 h was identical to the one observed after 96 h. This is indicative for pH induced toxicity (pH 10.2 reported for 100 mg/L).

Description of key information

Oncorhynchus mykiss: LC50(96h) = 40 mg/L; LC0 (96h) = 25 mg/L; nominal

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

40 mg/L

Additional information

Two valid and reliable short-term toxicity studies on freshwater fish are available.

Both studies are comparable; they show consistent results with LC0 values of 25 mg/L.

The LC50 was lower in the study with Rainbow trout (Oncorhynchus mykiss) than in the study with Pumpkinseed (Lepomis gibbosus), which is why the study with Rainbow trout was selected as key study.

No data on marine fish have been located. It is assumed that marine fish respond without substantial difference from freshwater fish.

Key study:

Toxicity of isopropylamine to freshwater fish was assessed in a pre-guideleine study equivalent to OECD 203 (adopted in July 1992), with acceptable restrictions (RL2). The tested freshwater species was Rainbow trout (Oncorhynchus mykiss). Per concentration 10 fish were tested. The following 8 test item concentrations (nominal) were applied: 1, 10, 16, 25, 40, 63, 80 and 100 mg/L. The concentrations 1, 10 and 100 mg/L were applied in the first and the concentrations 16, 25, 40, 63 and 80 mg/L in the second part of the experiment. No chemical analysis of the test item concentrations was performed. However, based on the very high water solubility of the compound (miscible in a 1 : 1 ratio mixture (w/w) with water (at 20°C)), the very low adsorption potential (read across from n-butylamine (source): experimentally determined Koc from batch-equilibrium test: approx. 43.2 L/kg) and being not volatile (fully ionized at environmental pH) it may be assumed with high confidence that the test item was stable during the test. While not all validity criteria specified in OECD 203 could be assessed directly, taking all information given into account, it is highly probable that all validity criteria were met.

Results:

At the lower test item concentrations applied (1, 10, 16, 25 mg/L), no mortality was observed during the 96h of the test. At the concentration 40 mg/L, mortality was 50% and at 63, 80 and 100 mg/L, mortality was 100%. The LC50 (96 h) was identified as 40 mg/L.

Manifestation of symptoms went in line with significantly elevated pH values (16 mg/L test item concentration and higher), lethality after 48h was identical to the one observed after 96h. This is indicative for pH-induced toxicity (pH 10.2 reported for 100 mg/L).

Supporting study:

Toxicity of isopropylamine to freshwater fish was assessed in a pre-guideleine study equivalent to OECD 203 (adopted in July 1992), with acceptable restrictions (RL2). The tested freshwater species was Pumpkinseed (Lepomis gibbosus). Per concentration 10 fish were tested. The following 9 test item concentrations (nominal) were applied: 10, 16, 25, 40, 63, 71, 80, 90, 100. The concentrations 10, and 100 mg/L were applied in the first, 16, 25, 40 and 63 mg/L in the second and 71, 80 and 90 mg/L in the third part of the experiment. No chemical analysis of the test item concentrations was performed. However, based on the very high water solubility of the compound (miscible in a 1 : 1 ratio mixture (w/w) with water (at 20°C)), the very low adsorption potential (read across from n-butylamine (source): experimentally determined Koc from batch-equilibrium test: approx. 43.2 L/kg) and being not volatile (fully ionized at environmental pH) it may be assumed with high confidence that the test item was stable during the test. While not all validity criteria specified in OECD 203 could be assessed directly, taking all information given into account, it is highly probable that all validity criteria were met.

Results:

At the test item concentrations 10, 16, 25 and 63 mg/L, no mortality was observed during the 96h of the test. At the concentrations 40, 71 and 80 mg/L, mortality was 10%. At 90 and 100 mg/L mortality was 60% and 100%, respectively. The LC50 (96h) was identified as 88 mg/L.

Overall conclusion

The LC50 (96h) was 40 mg/L in Rainbow trout (Oncorhynchus mykiss) and 88 mg/L in Pumpkinseed (Lepomis gibbosus).

The Rainbow trout is apparently more sensitive than the Pumpkinseed. Therefore, as a conservative approach, an LC50 of 40 mg/L for freshwater fish serves as a basis for classification and labelling as well as for environmental hazard and risk assessment. Both studies were performed without adaption of pH (ca. 10.2 at 100 mg/L). Accordingly, effects could be increased or even caused by the alkaline pH.