Benzoic acid, compound with cyclohexylamine (1:1)

Sediment toxicity

Link to relevant study record(s)

Reference

Endpoint:

sediment toxicity: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20 January to 30 Novemver 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Reliable experimental study following OECD guidelines (not specified), PARCOM (1995) – A sediment bioassay using an amphipod Corophium sp. and GLP standards.

Qualifier:

according to guideline

Guideline:

other: PARCOM (1995) – A sediment bioassay using an amphipod Corophium sp.

Version / remarks:

1995

Deviations:

yes

Remarks:

Where dissolved oxygen levels were found to be below 85%, extra airlines were added to the test vessel and the test was allowed to proceed at the study director’s discretion

GLP compliance:

yes

Specific details on test material used for the study:

The test substance is cyclohexylamine benzoate. The test substance was obtained from the study Sponsor on 5th September 2002 and stored in the original container at 15 ± 2°C.

Analytical monitoring:

not specified

Vehicle:

no

Details on sediment and application:

Sediment was collected from the same site as the amphipods, the North Wales coast, and sieved to remove organisms and debris and stored in sealed containers until later use.

Test organisms (species):

Corophium volutator

Details on test organisms:

The test was carried out using a batch of the marine amphipods, Corophium volutator, freshly dug from the North Wales coast on 14 January 2003 and free of malformations and of good health.

Study type:

laboratory study

Test type:

static

Water media type:

saltwater

Type of sediment:

natural sediment

Limit test:

no

Duration:

10 d

Exposure phase:

total exposure duration

Test temperature:

13.0 °C to 13.5 °C

pH:

7.22 to 8.46

Dissolved oxygen:

84.9 % to 96.7% air saturation values (ASV)

Salinity:

25 - 35 parts per thousand.

Nominal and measured concentrations:

An experimental study was conducted with test concentrations of 1,000.0, 1,778.3, 3,162.3, 5,623.4, and 10,000.0 mg/kg dry weight sediment.

Reference substance (positive control):

not specified

Key result

Duration:

10 d

Dose descriptor:

LC50

Effect conc.:

1 971.8 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

10 d

Dose descriptor:

NOEC

Effect conc.:

< 1 000 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

10 d

Dose descriptor:

LOEC

Effect conc.:

1 000 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

The test amphipods at all concentration levels tested reached the sediment surface within 10 minutes of addition to the test vessels.

Reported statistics and error estimates:

The mortality data calculated at the end of the test period was processed using the statistical computer programme Toxcalc, supplied by Tidepool Scientific. Toxcalc is used to derive the median effect concentration (LC50) which kills (immobilises) 50% of the animals exposed to the test material, together with 95% fiducial limits and a No Observed Effect Concentration (NOEC).

Validity criteria fulfilled:

not specified

Conclusions:

The test substance induced mortality of Corophium volutator at the nominal test concentrations after 10 days of exposure. The 10-d LC50 value was reported as 1,971.8 mg/kg dry weight of sediment. The 10-d NOEC and 10-d LOEC values were reported as <1,000 mg/kg dry weight of sediment and = 1,000 mg/kg dry weight of sediment, respectively.

Description of key information

The key study was a static acute invertebrate toxicity test on the effects of the substance on the marine sediment re-worker amphipod, Corophium volutator, following PARCOM protocol (PARCOM 1995). The test substance induced mortality of Corophium volutator at the nominal test concentrations after 10 days of exposure. The 10-d LC50 value was estimated to be 1,971.8 mg/kg dry weight of sediment.  The 10-d NOEC and 10-d LOEC values were reported as <1,000 mg/kg dry weight of sediment and = 1,000 mg/kg dry weight of sediment, respectively.

Key value for chemical safety assessment

EC50 or LC50 for marine water sediment:

1 971.8 mg/kg sediment dw