N,N-bis(2-hydroxypropyl)benzamide

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:

From July 9th to August 30th, 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

For the analysis of the actual test item concentrations the following samples were taken:
Just before test start: - duplicate samples from each test medium
- duplicate samples from the control
After 48 and 96 hours (stability samples): - duplicate samples from each test medium
- duplicate samples from the control

All samples were taken from the approximate center of the aquaria and were deep-frozen (at about -20 °C) immediately after sampling. Based on pre-experiments for investigation of the storage stability (non-GLP) the test item is sufficiently stable in the test water under these storage conditions.
The concentration of test item was analyzed in the test medium samples of the highest test concentration from the sampling times at 0 and 96 hours. The lower test concentrations were not analyzed, since they were below the 96-hour NOEC, determined in the test. From the control samples only one of the duplicate samples was analyzed from the corresponding sampling times.

Vehicle:

no

Details on test solutions:

Test solutions for each concentration were freshly prepared by dissolving test item in test water (e.g. for the 100mg/L solution, 1000mg of test item dissolved in 10 liters of test water), using ultrasonic treatment and stirring at room temperature (15 minutes each). Adequate volumes of this intensively stirred medium were added to test water in aquaria and were intensively mixed to prepare test media. Test media were freshly prepared just before introduction of fish.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

Test fish were obtained from Zoohaus Schaub, CH-4410 Liestal, Switzerland. In accordance with testing guidelines, fish were held in the laboratories of RCC for about two weeks without any medication. Prior to test start, they were acclimated for one week to the test water and temperature. During holding and acclimatization until one day before the start of the test, the fish were fed with a commercial fish diet (TETRA MIN Haupfutter, supplied by TETRA-Werke, D-49304 Melle, Germany). During holding and acclimatization no fish died in the test fish batch and all fish were healthy.
From the acclimated test fish batch, 10 fish were measured at the start of the test: the mean body lenght was 2.9 ± 0.2 cm, the mean body wet weight was 0.20 ± 0.04 g.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

Not specified

Hardness:

2.5 mmol/L (250 mg/L) as CaCO3

Test temperature:

22-23 °C

pH:

8.0

Dissolved oxygen:

8.2-8.6 mg/L, considering all concentrations and all exposure times.

Salinity:

Analytical grade salts were dissolved in purified water to obtain the following nominal concentrations:
CaCl2 * 2H2O: 2.0 mmol/L
MgSO4 * 7H2O: 0.5 mmol/L
NaHCO3: 0.75 mmol/L
KCl: 0.075 mmol/L

Conductivity:

Not specified

Nominal and measured concentrations:

Control: 0 mg/L
Nominal concentrations: 4.6, 10, 22, 46, 100 mg/L

Details on test conditions:

One glass aquarium with 5 liters test medium was used for each test concentration and the control. Test vessels were labeled with RCC study number and all necessary additional information to assure unmistakable identification. At the start of the test 7 fish were introduced into each aquarium in a random order. The loading rate was lower than 1g fish wet weight per liter of test medium. The test media and the control were slightly aerated during the test period. The fish were not fed during the test.
Light conditions: A 16-hour light to 8-hour darkness photoperiod, with a 30 minutes transition period (light intensity approximately from 50 to 500 Lux).

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Signs of intoxication

Details on results:

The analytically determined test item concentrations in the analyzed test media varied in the range from 101 to 107% of the nominal values. Consequently, test item was stable during the test period and the results were reported using nominal concentrations.
All fish survived and no signs of intoxication were observed at any tested concentration, as well as in the control.
No remarkable observations were made concerning the appearance of the test media. All test media were clear solutions throughout the test period.

Results with reference substance (positive control):

Not performed

Validity criteria fulfilled:

yes

Conclusions:

The substance is not acutely toxic to fish at a concentration up to 100 mg/L. Therefore, 96-hour LC50 of the substance is higher than 100 mg/L

Executive summary:

Acute aquatic toxicity to fish was evaluated in a 96 -hour static study on Zebra fish, in accordance with OECD TG 203.

The nominal concentrations tested were 4.6, 10, 22, 46 and 100 mg/L.

The analytically determined test item concentrations in the analyzed test media varied in the range from 101 to 107% of the nominal values (see attached background material). Consequently, test item was stable during the test period and the results were reported using nominal concentrations. All fish survived and no signs of intoxication were observed at any tested concentration, as well as in the control. No remarkable observations were made concerning the appearance of the test media. All test media were clear solutions throughout the test period.

Therefore, the substance is not acutely toxic to fish at a concentration up to 100 mg/L. Thus, 96-hour LC50 of the substance is higher than 100 mg/L.

Description of key information

In a study according to OECD TG 203, the substance did not show any effect on fish after 96 hours of exposure at concentrations up to 100 mg/L. Therefore, LC50 (96h, Danio Rerio) > 100 mg/L

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L