Alkali salt of substituted alkyl amino sulfonyl triazinyl amino arylamido diazo aryl sulfonyl sulfonate

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2018-10-15 to 2019-04-28

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

2012

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: The Guidelines for the Testing of Chemicals, Effects on Biotic Systems, 211 "Daphnia magna Reproduction Test", China Environment Press

Version / remarks:

second edition, 2013.8

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The concentrations of test item were determined at 0, 2, 7, 9, 14, 16 d in fresh media and 2, 5, 9, 12, 16, 19 d in old media, in the control and test concentrations. 20 mL solution were sampled directly and filtered with 0.45 μm membrane to sample vial and the rest was stored in refrigerator (2 - 8 °C) for possible re-analysis and until the end of the test.

Vehicle:

no

Details on test solutions:

0.02000 ~ 0.02002 g of the test item were weighed out and directly dissolved in 2 L test water (tap water treated with Aquapro Pure Warer System). Afterwards, the test item was thoroughly dissolved by stirring to get the solution of nominal concentration of 10 mg/L. The solution was used for exposure and as stock solution to prepare lower test concentrations. About 100 mL of each solution were dispensed into each test vessel for each concentration.

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia of stock culture were originally obtained from Applying Chemistry Department Pesticide Environmental Evaluation Laboratory of China Agricultural University. The test Daphnia were derived from a same healthy pre-cultured population (i.e. showing no signs of stress such as high mortality, presence of males and ephippia, delay in the production of the first brood, discoloured animals, etc.). The pre-cultured animals were maintained under culture conditions (light, temperature, and medium) similar to those that were in the test. The test animals were less than 24 hours old and not the first brood progeny.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

180 mg CaCO3 /L (dilution water)

Test temperature:

18.3 - 21.6°C

pH:

7.7 - 8.2

Dissolved oxygen:

8.6 - 9.6 mg/L

Salinity:

N/A

Nominal and measured concentrations:

Nominal: 0.625, 1.25, 2.5, 5, 10 mg/L
Measured (geometric mean): 0.637, 1.323, 3.011, 6.020, 10.747 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: beaker
- Type: loosely covered
- Material, size, headspace, fill volume: glass, 250 mL total volume, 100 mL fill volume
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): three times a week
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: tap water
- Total organic carbon: < 2 mg/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: every three months

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light : 8 h dark
- Light intensity: 1000 - 1500 lux cool white light

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality, reproductive output per surviving parent animal, length of living parent animals, total number of broods per parent, first brood time

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 10 mg/L (21 d)
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

K2Cr2O7

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1.195 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1.195 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality: Number of living offspring produced per surviving parental animal {for Daphnia magna, TG 211}

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

11.016 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks:

parental animals

Details on results:

- Behavioural abnormalities: None
- Observations on body length and weight: NOEC (length of parent) = 11.016 mg/L
- Other biological observations: None
- Mortality of control: None

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: 24-h EC50 = 1.34 mg/L corresponding to a normal sensitivity

Reported statistics and error estimates:

N/A

Validity criteria fulfilled:

yes

Conclusions:

The substance showed a 21-d NOEC (reproduction) of 1.195 mg/L to Daphnia magna in an OECD 211 guideline study. The substance concentration were analytically verified. The substance is not considered to be chronically toxic to aquatic invertebrates.

Executive summary:

A Daphnia magna Reproduction Test was conducted with Daphnia magna over a 21 days exposure period.

Based on the results of the preliminary test, the definitive test was carried out at concentrations of 0.625, 1.25, 2.5, 5 and 10 mg/L (nominal concentration). A concurrent blank control was performed in parallel. 10 daphnids individually held were used for each test group and the control group. The actual concentrations of test solutions were measured with an HPLC method.

Based on the results of the preliminary test, a semi-static system with solution renewed at three times a week, on every Monday, Wednesday and Friday was used in the definitive test.Oxygen concentration and pH values weremeasured twice a week, in fresh and old media,duringthe 21 days exposure periodin the control and in the testitemconcentration.Total hardnesswasmeasured in the controlonce a week.Temperature was continuously monitored and recorded by an automatic temperature monitoring system.

The concentrations ofthe test itemwere determined in samples of the test media by HPLC method. The results showed thatfor the test solutions of 0.625, 1.25, 2.5, 5 and 10 mg/L,the geometric mean determined concentrations in fresh media were 0.637, 1.323, 3.011, 6.020 and 10.747 mg/L. The geometric mean determined concentrations in old media were 0.250, 1.080, 2.429, 5.289 and 11.291 mg/L. The overall geometric mean determined concentrations were 0.399, 1.195, 2.551, 5.325 and 11.016 mg/L corresponding to 63.8% for 0.625 mg/L and 95%-110% of the nominal values for other concentrations.

Total number ofliving offspring per parent, body length of parent, maternal mortality, first brood time and total number of broods per parent wereanalyzed by a two-sided Student´s T-test using a 5% significancelevel to obtain the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC).

The 21-day NOEC and LOEC for all the parameters based on the measured concentration were as below:

Parameter	NOEC (Measured concentration)	LOEC (Measured concentration)
Total number ofliving offspring per parent	1.195 mg/L	2.551 mg/L
Body length of parent	11.016 mg/L	> 11.016 mg/L
Mortality parent	11.016 mg/L	> 11.016 mg/L
First brood time	11.016 mg/L	> 11.016 mg/L
Total number of broods per parent	1.195 mg/L	2.551 mg/L

The EC10 of test item to total living offspring per parent was calculated by using EPA PROBIT ANALYSIS PROGRAM USED FOR CALCULATION LC/EC VALUES (Version 1.5). The EC10 of test item to total living offspring per parent was 1.187 mg/L, with 95% confidence limit of 0.767-1.591 mg/L based on measured concentration.

Description of key information

The substance showed a 21-d NOEC (reproduction) of 1.195 mg/L to Daphnia magna in an OECD 211 guideline study. The substance concentration were analytically verified. The substance is not considered to be chronically toxic to aquatic invertebrates.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1.195 mg/L