Dimethyl 2-aminoterephthalate

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed according to current OECD-Guideline and GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Dimethyl 2-aminoterephthalate

EC Number:

226-364-2

EC Name:

Dimethyl 2-aminoterephthalate

Cas Number:

5372-81-6

Molecular formula:

C10H11NO4

IUPAC Name:

1,4-dimethyl 2-aminobenzene-1,4-dicarboxylate

Constituent 2

Reference substance name:

dimethyl-2-aminoterephthalate

IUPAC Name:

dimethyl-2-aminoterephthalate

Details on test material:

> 99,9 % (m/m)
brown powder

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
The test substance was weighed into a beaker Water for dilution (pH 6.5) was added and the mixture homogenized using an Ultra-Turrax and Ultrasonic Bath and poured into the chamber under stirring with a glass rod. The chamber contents were then stirred for approx 30 min with a KPG stirrer and a glass rod. All tested concentrations were present as clear solutions. Additionally substance deposits on the bottom of the test chambers and at the water surface were recorded. In order to determine the subtsance concentration, water samples were taken from the middle of the test chamber of each first and thrid preparation of a concentration after 0 and 24 hours, respectively.

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

In order to determine the substance concentration, water samples were taken from the middle of the test chamber of each first and third preparation of a concentration after 0 and 24 hours, respectively.

Test solutions

Vehicle:

yes

Details on test solutions:

Water for dilution
Reconstituted water, composition according to ISO/DIS 7346/1 was used as water for dilution. Preparation was carried our in a unit sonsisting of two Hostalen-lined steel vessels with a capacity of 1000 litres each. The dilution water was prepared as described and aerated until oxygen saturation.
Samples were diluted with methanol.

To establish a stable concentration level of the test substance in water, the pH-value of the test water was adjusted to approx. pH 6.5 in each fresh preparation of the study. The measured pH values at study start were in a range of 6.3 to 6.6. The total hardness of the dilutionw ate rwas ddteremiend weekly and was in a range of 2.3 to 2.5 mmol Ca2+ + Mg2+/L during the study.

Test organisms

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

date of hatching: 10.08.1994, 04.10.1994
delivery date: 06.10.1994, 16.10.1994
The fish were kept at least 12 days before the start of the study in water for dilution under the following conditions:
Temperature: 22 +/- 1°C
Oxygen content: >= 80 % for the saturation value
Duration of light period: 12 hours daily
Population density: <= 1 g fish / L water
Feeding: twice daily ad libitum
Feed: Tera Min, Tetra Werke, Melle, FRG
Body length of 7 representative fish from each batch was measured:
Part 1 of study: date 16.01.1995: n = 7, mean length 3.2 cm s = +/- 0.22
Part 2 of study: date 23.01.1995, n = 7, mean length 2.8 cm, s = +/- 0.16
total sample: n = 14, mean length 3.0 cm, s = +/- 0.29

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

12 days

Test conditions

Hardness:

The total hardness of the dilution rate was determined weekly and was in a range of 2.3 to 2.5 mmol Ca2+ + Mg2+/L during the study.

Test temperature:

22 +/- 1 °C
concentration group 21.5 - 22.8 °C, controls 21.5 - 22.7 °C
electronic measurement using oxygen meter OXI 196 (WTW) and oxygen elctrode EO 196-1.5 with inbuilt tempreature sensor (Wissenschaftlich Technische WErkstätten, Weilheim, FRG)

pH:

To establish a stable concentration level of the test substance in water, the pH-value of the test water was adjusted to approx. pH 6.5 in each fresh preparation of the study. The measured pH values at study start were in a range of 6.3 to 6.6
concentration group: 6.3 - 7.0 and controls 6.2 - 7.1
electronic measurement using pH meter pH 763 (KNick) and combined electrode (Schott-Geräte GmbH, Hofheim, FRG)

Dissolved oxygen:

Oxygen content mg/l: concentration groups 21.5 - 22.8 and controls 21.5 - 22.7

electronic measurement using oxygen meter OXI 196 (WTW) and oxygen elctrode EO 196-1.5 (Wissenschaftlich Technische WErkstätten, Weilheim, FRG)

Nominal and measured concentrations:

Preparation of test concentrations:
The test substance was weighed into a beaker Water for dilution (pH 6.5) was added and the mixture homogenized using an Ultra-Turrax and Ultrasonic Bath and poured into the chamber under stirring with a glass rod. The chamber contents were then stirred for approx 30 min with a KPG stirrer and a glass rod. All tested concentrations were present as clear solutions. Additionally substance deposits on the bottom of the test chambers and at the water surface were recorded. In order to determine the substance concentration, water samples were taken from the middle of the test chamber of each first and thrid preparation of a concentration after 0 and 24 hours, respectively.
The follwoing values were determined during the study:
nominal 5 mg/l = measured mean 2.3 mg/l = 46.3 %
nominal 10 mg/l = measured mean 5.1 mg/l = 50.5 %
nominal 22 mg/l = measured mean 9.14 mg/l = 41.5 %
nominal 50 mg/l = measured mean 17.84* mg/l = 35.7 %; * mean of samples taken after 0 and 48 hours
nominal 100 mg/l = measured mean 27.23* mg/l = 27.23 % * mean of samples taken after 0 and 48 hours
The values determined at the start of the intervals were in a range of 23-38 % of the nominal concentrations. Samples taken after 24 hours revealed increasing values between 31 and 71 % of the theoretical conccentration. In preliminary thests the test substance showed a very slow solubility kinetic and additionally an insufficient chemical stability in water over 96 h. Therefore the test was carried our in a semistatic system and concentration values given in this report are based on the mean of the analytical measured concentration values.

Details on test conditions:

Water for dilution
Reconstituted water, composition according to ISO/DIS 7346/1 was used as water for dilution. Preparation was carried our in a unit sonsisting of two Hostalen-lined steel vessels with a capacity of 1000 litres each. The dilution water was prepared as described and aerated until oxygen saturation. To establish a stable concentration level of the test substance in water, the pH-value of the test water was adjusted to approx. pH 6.5 in each fresh preparation of the study. The measured pH values at study start were in a range of 6.3 to 6.6. The total hardness of the dilutionw ate rwas ddteremiend weekly and was in a range of 2.3 to 2.5 mmol Ca2+ + Mg2+/L during the study.

Test conditions:
The study was conducted in a semistatic system. The fish were transferred to new test chambers every 24 hours. The test chambers were calibrated to 10 litres, were made of glass (length 30 cm , width 22 cm, height 24 cm) and stood in a water ath made of Hostalit Z with a Plexiglas viewing panel. The temperature of the water bath was regulated by a thermostat to 22 +/- 1 °C. The chambers were iluminated from above from 6.00 a.m. to 6.00 p.m. The light intensity directly over the chambers was approx. 700 lux.The test chambers were not aerated during the course of the study.

Evaluation: Probit analysis could not be carried our because of the lethality rate. As the factor for the concentration steps was >2, no further concentrations were tested. The LC50 range is given.

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

5.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

>= 9.1 - <= 17.8 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 3

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

17.8 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

The surviving fish of 9.1 and 27.2 mg/l groups showed changes in appaearance and behaviour, swimming behaviour and respiration rate during the entire exposure time. The fish in the 2.3 and 5.1 mg/l groups showed changes in behaviour, swimming behaviour and respiration rate.
Dead fish showed dark or light colored integrument, red opercula and lock-jaw.

Results with reference substance (positive control):

The control groups with 0 mg/l did neither show any lethality (0/14) nor any changes in appearance and behaviour.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 96-hour acute tox study of test item in zebra fish was conducted in a semistatic system, because in a static system the test item showed no sufficient stability in water over 96 hours. To improve the stability of test item in water, the pH-value was adjusted to approx. pH 6.5 in each fresh prepared test batch.
The nominal test concentrations tested were 5, 10, 22, 50, 100 mg/L and a negative control (0 mg/l)

Letality values:
LC 0: after 24 h = 5.1 mg/l, after 48 h = 5.1 mg/lg, after 72 h = 5.1 mg/l, after 96 h = 5.1 mg/l
LC 50: after 24 h = 9.1 - 17.8 mg/l, after 48 h = 9.1 - 17.8 mg/lg, after 72 h = 9.1 - 17.8 mg/l, after 96 h = 9.1 - 17.8 mg/l
LC 100: after 24 h = 17.8 mg/l, after 48 h = 17.8 mg/lg, after 72 h = 17.8 mg/l, after 96 h = 17.8 mg/l
Symptoms and lethality were observed at 9.1, 17.8 and 27.2 mg/l. The 2.3 and 5.1 mg/l gourps exhibited symptoms but no lethality.

Executive summary:

The nominal test concentrations tested were 5, 10, 22, 50, 100 mg/L and a negative control (0 mg/l)

Letality values:

LC 0: after 24 h = 5.1 mg/l, after 48 h = 5.1 mg/lg, after 72 h = 5.1 mg/l, after 96 h = 5.1 mg/l

LC 50: after 24 h = 9.1 - 17.8 mg/l, after 48 h = 9.1 - 17.8 mg/lg, after 72 h = 9.1 - 17.8 mg/l, after 96 h = 9.1 - 17.8 mg/l

LC 100: after 24 h = 17.8 mg/l, after 48 h = 17.8 mg/lg, after 72 h = 17.8 mg/l, after 96 h = 17.8 mg/l

Symptoms and lethality were observed at 9.1, 17.8 and 27.2 mg/l. The 2.3 and 5.1 mg/l gourps exhibited symptoms but no lethality.