Nonanoic acid

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Study performed in 1993.

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Justification for type of information:

The following information is available from the "OPP Pesticide Ecotoxicity Database" home page (https://ecotox.ipmcenters.org/) relating to reliability of the source data:
"The toxicity data input into the database is compiled from actual studies reviewed by EPA in conjunction with pesticide registration or re-registration and studies performed by US EPA, USDA and US FWS laboratories which have been reviewed by Agency biologists and judged acceptable for use in the ecological risk assessment process."
Further details on this study (MRID number: 43065303) were obtained via personal communication with US EPA (reference: T11302)

Qualifier:

according to guideline

Guideline:

EPA OPP 72-2 (Aquatic Invertebrate Acute Toxicity Test)

Version / remarks:

Freshwater invertebrate acute; 72-2/850.1010

Deviations:

no

Remarks:

According to T11302

GLP compliance:

yes

Remarks:

According to T11302

Analytical monitoring:

yes

Remarks:

According to T11302

Details on sampling:

not available

Vehicle:

no

Remarks:

No surfactant or dispersant used; no data on solvent use available - according to the guideline validity criteria, any solvent used had to conform with guideline criteria: <= 0.1 mL/L for recommended solvents (OCSPP 850.1000), including a solvent control

Details on test solutions:

not available

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: no data
- Source: no data
- cultured at the test facility, all organisms used originating from the same stock;
- Age at study initiation (mean and range, SD): < 24 h


ACCLIMATION
- Acclimation period: culture condition similar to test conditions; brood daphnids maintained in dilution water at the test temperature for at least 48 hours prior to the start of the test.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

not applicable

Hardness:

< 250 mg/L (as CaCO3), no further details available

Test temperature:

according to guideline specification, i.e. ca. 20 °C (within 18-22 °C), kept constant during the test within (±) 1 °C.

pH:

according to guideline specification, i.e. between limits of 6.0 and 8.5, with a variation during the test of less than 1 pH unit

Dissolved oxygen:

>60 % saturation for all concentration levels and the control

Salinity:

not applicable

Conductivity:

not avialable

Nominal and measured concentrations:

At least 5 test item concentrations were used. Further data are not available.

Details on test conditions:

A minimum of 20 daphnids was divided into a minimum of 2 replicates, each with >=10 daphnia. Each test vessel contained an equal volume of test solution and an equal number of daphnids. Replicate test vessels were physically separated (experimental unit = test vessel).
Start of the test: by introducing <24-hour old daphnids (from acclimated parents).
Test vessels were loosely covered to reduce the loss of test solution or dilution water due to evaporation.
Light intensity: between 540-1080 lux;
Light regime: according to the guideline, i.e. from 12 hours light:12 hours dark to 16 hours light:8 hours dark;
Observations: immobilization; any abnormal behaviour or appearance;
Feeding: No feeding during test;
Aeration: no;

Reference substance (positive control):

not specified

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

96 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL: 64-119 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

39 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Reported statistics and error estimates:

95% confidence interval: 64 mg/L to 119 mg/L

Validity criteria fulfilled:

yes

Remarks:

based on T11302

Conclusions:

48-h EC50 (Daphnia magna; immobilization): 96 mg/L (mean measured; 95% CI: 64-119 mg/L; EPA OPP, 2000)

Executive summary:

The acute aquatic toxicity towards the aquatic invertebrate Daphnia magna was assessed in a static test according to EPA OPP 72-2/850.1010 (EPA OPP, 2000). The full study report was not available, but essential data are reported within US EPA "OPP Pesticide Ecotoxicity Database". This database is a reliable source, because according to DB homepage "The toxicity data input into the database is compiled from actual studies reviewed by EPA in conjunction with pesticide registration or re-registration and studies performed by US EPA, USDA and US FWS laboratories which have been reviewed by Agency biologists and judged acceptable for use in the ecological risk assessment process." Additional details were retrieved via personal communication with US EPA. Accordingly, the study was performed without any deviations from the guideline, compliant with GLP. All validity criteria of the guideline were met. During the static study, test item concentrations were analytically verified, and effect concentrations are given based on mean measured values.

The following results were obtained:

EC50 (48 h; static; immobilization; mean measured) = 96 mg/L (95% CI: 64-119 mg/L);

NOEC (48 h; static; immobilization; mean measured) = 39 mg/L

Description of key information

48-h EC50 (Daphnia magna; immobilization): 96 mg/L (mean measured; 95% CI: 64-119 mg/L; EPA OPP, 2000)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

96 mg/L

Additional information

The acute aquatic toxicity towards the aquatic invertebrate Daphnia magna was assessed in a static test according to EPA OPP 72-2/850.1010 (EPA OPP, 2000). The full study report was not available, but essential data are reported within US EPA "OPP Pesticide Ecotoxicity Database". This database is a reliable source, because according to DB homepage "The toxicity data input into the database is compiled from actual studies reviewed by EPA in conjunction with pesticide registration or re-registration and studies performed by US EPA, USDA and US FWS laboratories which have been reviewed by Agency biologists and judged acceptable for use in the ecological risk assessment process." Additional details were retrieved via personal communication with US EPA. Accordingly, the study was performed without any deviations from the guideline, compliant with GLP. All validity criteria of the guideline were met. During the static study, test item concentrations were analytically verified, and effect concentrations are given based on mean measured values.

The following results were obtained:

EC50 (48 h; static; immobilization; mean measured) = 96 mg/L (95% CI: 64-119 mg/L);

NOEC (48 h; static; immobilization; mean measured) = 39 mg/L