Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
GLP compliance:
yes (incl. QA statement)
Test organisms (species):
Daphnia magna
Hardness:
Between 140 and 250 mg.L-1
Test temperature:
20 °C ± 2
pH:
Between 6 and 9
Details on test conditions:
Light/dark cycle: 16 h/8 h
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.317 mg/L
Nominal / measured:
meas. (initial)
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
0.317 mg/L
Nominal / measured:
meas. (initial)
Conc. based on:
test mat.
Basis for effect:
mobility
Validity criteria fulfilled:
yes
Conclusions:
According to an experimental study performed on isoamyl nitrite according to the OECD TG 202 and under GLP conditions, the 48h-EC50 was found to be 0.317 mg/L based on measured concentrations.
Executive summary:

The objective of this study was to assess the effects of the test item Isoamyl Nitrite on the mobility of Daphnia magna over a period of 48 hours under static conditions according to OECD Guideline 202 (April 2004).

Since the substance is volatile and is not soluble in under conditions of the test, the test was carried out in closed bottles and the substance was added by injection through the septum.

Test item quantification was performed according to a validated analytical method (final report RRCo-000234_01) on a GC-MS/MS from Agilent (GC 7890b and MS triple quadrupole 7000b or c) as mass spectrometry detection was found suitable to measure Isoamyl Nitrite concentrations at 0 and 48 hours.

Results are the following:

Isoamyl Nitrite

EC50 (24h) 0.317 mg.L-1 (0.307 – 0.327 mg.L-1)

EC50 (48h) 0.317 mg.L-1 (0.307 – 0.327 mg.L-1)

The acute effects of Isoamyl Nitrite at the definitive nominal concentrations of 0; 0.31; 0.63; 1.25; 2.5 and 5 mg.L-1 to Daphnia magna were investigated under laboratory conditions.

Due to the instability of test item, the calculations were performed on the measured concentrations at initial time.

The study is valid since immobilization in the control was less than 10% (actual values: 0% in the definitive test), dissolved oxygen in the lowest concentration producing the maximum effect at the end of the test was ≥ 3 mg.L-1 (actual values: 8.5 mg.L-1 in the definitive test) and the EC50 with reference item over a period of 24 hours was between 0.6 and 2.1 mg.L-1 (actual value: 1.44 mg.L-1).

Endpoint:
short-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:
SOURCE AND TARGET CHEMICAL(S)
The read-across has been performed between pentyl nitrite (CAS No. 463-04-7; target chemical) and isoamyl nitrite (CAS No. 110-46-3; source chemical). The RA is based on an experimental study performed on the source substance having a purity of 98.1%, in accordance with the OECD TG 202 and under GLP conditions.

ANALOGUE APPROACH JUSTIFICATION
The source substance and the target substance have the same chemical formula (C5H11NO2) and belong to the alkyl nitrites family. Like other alkyl nitrites, chemical and biological properties are mainly due to the nitrite group. Both target and source substances have similar physico-chemical properties.
For all these reasons, it is expected that the registered substance pentyl nitrite will have a similar ecotoxicity than the source substance isoamyl nitrite. The read-across approach between both alkyl nitrite substances is therefore considered relevant for this endpoint.
Isoamyl nitrite was found to be acutely toxic on aquatic invertebrates with an 48h-EC50 of 0.317 mg/L. The study was performed according to the OECD TG 202 under GLP conditions and all validity criteria were successful. This experimental study was therefore considered acceptable.
It is expected that similar results would be also found if a test was performed with pentyl nitrite. Due to the absence of experimental data on pentyl nitrite, it is therefore considered relevant to extrapolate results from the study on isoamyl nitrite to the registered substance.
Reason / purpose for cross-reference:
read-across source
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.317 mg/L
Nominal / measured:
meas. (initial)
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
0.317 mg/L
Nominal / measured:
meas. (initial)
Conc. based on:
test mat.
Basis for effect:
mobility
Validity criteria fulfilled:
yes
Conclusions:
Based on a read-across on an experimental study performed on another alkyl nitrite substance (isoamyl nitrite) in accordance with the OECD TG 202 and under GLP conditions, the registered substance pentyl nitrite is considered acutely toxic to aquatic invertebrates.
Executive summary:

For that endpoint, a read-across was performed between pentyl nitrite (CAS No. 463-04-7; target chemical) and isoamyl nitrite (CAS No. 110-46-3; source chemical).

The source substance and the target substance have the same chemical formula (C5H11NO2) and belong to the alkyl nitrites family. Like other alkyl nitrites, chemical and biological properties are mainly due to the nitrite group. Both target and source substances have similar physico-chemical properties.

For all these reasons, it is expected that the registered substance pentyl nitrite will have a similar ecotoxicity than the source substance isoamyl nitrite. The read-across approach between both alkyl nitrite substances is therefore considered relevant for this endpoint.

An experimental study performed on the source substance isoamyl nitrite was available, and was conduted according to the OECD TG 202 under GLP conditions. The objective of this study was to assess the effects of the test item Isoamyl Nitrite on the mobility of Daphnia magna over a period of 48 hours under static conditions according to OECD Guideline 202 (April 2004).

Since the substance is volatile and is not soluble in under conditions of the test, the test was carried out in closed bottles and the substance was added by injection through the septum.

Test item quantification was performed according to a validated analytical method (final report RRCo-000234_01) on a GC-MS/MS from Agilent (GC 7890b and MS triple quadrupole 7000b or c) as mass spectrometry detection was found suitable to measure Isoamyl Nitrite concentrations at 0 and 48 hours.

Results are the following for the source substance Isoamyl Nitrite:

EC50 (24h) 0.317 mg.L-1 (0.307 – 0.327 mg.L-1)

EC50 (48h) 0.317 mg.L-1 (0.307 – 0.327 mg.L-1)

The acute effects of Isoamyl Nitrite at the definitive nominal concentrations of 0; 0.31; 0.63; 1.25; 2.5 and 5 mg.L-1 to Daphnia magna were investigated under laboratory conditions.

Due to the instability of test item, the calculations were performed on the measured concentrations at initial time.

The study is valid since immobilization in the control was less than 10% (actual values: 0% in the definitive test), dissolved oxygen in the lowest concentration producing the maximum effect at the end of the test was ≥ 3 mg.L-1 (actual values: 8.5 mg.L-1 in the definitive test) and the EC50 with reference item over a period of 24 hours was between 0.6 and 2.1 mg.L-1 (actual value: 1.44 mg.L-1).

It is expected that similar results would be also found if a test was performed with pentyl nitrite. Due to the absence of experimental data on pentyl nitrite, it is therefore considered relevant to extrapolate results from the study on isoamyl nitrite to the registered substance.

Description of key information

Based on a read-across on an experimental study performed on another alkyl nitrite substance (isoamyl nitrite) in accordance with the OECD TG 202 and under GLP conditions, the registered substance pentyl nitrite is regarded as acutely toxic to aquatic invertebrates.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates
Effect concentration:
0.317 mg/L

Additional information