Quinazolin-4(1H)-one

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2018-03-14 to 2018-03-16

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Lot No. 20170707;
Purity: 99.13%

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 (control), 6.3, 13, 25, 50, and 100 mg/L
- Sampling method: At each sampling point (test initiation and termination), a 5-mL sample was collected from the control and each test substance treatment using a serological pipette, and the samples were placed in separate 10-mL culture tubes.
- Sample storage conditions before analysis: analysed immediately

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A 0.10 mg/mL primary standard was prepared at test initiation by diluting 0.2022 grams of test item to a volume of 2,000 mL with dilution water. The 6.3, 13, 25, and 50 mg/L test solutions were prepared by diluting appropriate aliquots of the primary standard solution to a volume of 1.0 L with dilution water. The primary standard was used as the 100 mg/L test solution.
- Controls: consisted of dilution water only

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna neonates
- Source: an in house daphnid culture
- Age of parental stock (mean and range, SD): approximately 30 days old
- Feeding during test: not fed

ACCLIMATION
- Acclimation period: no acclimation period

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

152 mg CaCO3/L

Test temperature:

19.7 to 20.3°C

pH:

8.4 to 8.6

Dissolved oxygen:

8.5 to 8.9 mg/L

Conductivity:

342 μS/cm

Nominal and measured concentrations:

Nominal: 0 (control), 6.3, 13, 25, 50, and 100 mg/L
Measured:

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL glass jars
- Type: closed, covered with a clear plastic petri dish
- Fill volume: 200 mL of control or test substance treatment solution
- Aeration: No aeration
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: a moderately hard freshwater prepared by blending naturally hard well water with well water that was demineralized by reverse osmosis (RO)

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16-hour daylight photoperiod with 30 minute simulated dawn and dusk periods
- Light intensity: 585 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
The daphnids were observed for immobility and sublethal effects at approximately 24 and 48 hours after test initiation.

RANGE-FINDING STUDY
- Test concentrations: 0 (control), 0.10, 1.0, 10, and 100 mg/L
- Results used to determine the conditions for the definitive study: After 48 hours of exposure, immobility was 0, 0, 10, 10, and 0%, in the 0 (control), 0.10, 1.0, 10, and 100 mg/L test substance treatments.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Analytical Results: Measured concentrations of test item in the test substance treatment solutions at initiation were 6.36 13.3, 24.9, 49.2, and 101 mg/L in the 6.3, 13, 25, 50, and 100 mg/L treatments, respectively, which represented recoveries of 98 to 102% of the nominal concentrations. Measured concentrations of test item in test solutions at 48 hours (termination) were 6.25, 12.3, 24.6, 49.3, and 97.7 mg/L, which represented recoveries of 94 to 99% of the nominal concentrations. The overall mean measured concentrations in the test substance treatment solutions during the 48-hour exposure were 6.30, 12.8, 24.8, 49.3, and 99.2 mg/L, which represented recoveries of 98 to 100% of the nominal concentrations.
- Biological Results: After 48 hours of exposure, immobility was 0% in the control and all test substance treatments, respectively.
- Test solution: The control and all test treatment solutions were clear and colorless with no visible particulates, surface film, undissolved test substance, or precipitate throughout the test.

Reported statistics and error estimates:

There was no mortality and sublethal effects in the control and test substance treatments, therefore no statistical analyses were necessary.

Validity criteria fulfilled:

yes

Conclusions:

The 24- and 48-hour EC50 values were estimated to be >100 mg/L, the highest concentration tested. The 48 hour NOEC was 100 mg/L, the highest concentration tested.

Executive summary:

A 48-hour static toxicity test was conducted with the freshwater invertebrate,Daphnia magna, exposed to test item according to OECD 202.

A definitive testwas performed at nominal concentrations of0 (control), 6.3, 13, 25, 50, and 100 mg/L. The control consisted of dilution water only. Five neonates (<24-hours old) were added to each of four test chambers per treatment at the start of the test. The daphnids were observed for immobility and sublethal effects at approximately 24 and 48 hours after test initiation.

After 48 hours of exposure, immobility was 0% in the control and all test substance treatments, respectively. No sublethal effects were noted during the definitive test. The 24- and 48-hour EC₅₀values were estimated to be >100 mg/L, the highest concentration tested. The 48‑hour NOEC was 100 mg/L, the highest concentration tested.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From 2007-01-29 to 2007-02-09

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch no.: LOT S17686-226
Purity: 99.7%

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100 mg/L
- Sampling method: duplicate samples from the test medium and control just before the start of the test and after 48 hours
- Sample storage conditions before analysis: stored deep-frozen at -18°C and protected from light

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test medium was prepared by mixing 30.1 mg of the test item into 300 mL of test water using ultrasonic treatment for 15 minutes and intense stirring for 3 hours at room temperature in the dark. Since the solution contained visible particles, the test medium was filtered through a membrane filter.
- Controls: test water without addition of the test item

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna Straus
- Strain/clone: clone 5
- Source: originally supplied by University of Sheffield/UK, bred in the laboratories in reconstituted water of the quality identical to the water quality used in the tests
- Age of parental stock (mean and range, SD): 6–24 hours old and were not first brood progeny
- Feeding during test: None

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

250 mg/L as CaCO3

Test temperature:

20 °C

pH:

7.7 and 7.8

Dissolved oxygen:

8.2 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass beakers
- Type (delete if not applicable): open / closed
- Fill volume: 50 mL of test medium
- Aeration: not aerated
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Biomass loading rate: 10 mL each daphnia

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted test water: analytical grade salts were dissolved in purified water to obtain nominal concentrations: CaCl2 × 2H2O : 2.0 mmol/L (= 294 mg/L); MgSO4 × 7H2O : 0.5 mmol/L (= 123 mg/L); NaHCO3 : 0.75 mmol/L (= 65 mg/L); KCl : 0.075 mmol/L (= 5.8 mg/L)
- Alkalinity: 0.8 mmol/L
- Ca/mg ratio: 4 : 1 (based on molarity)
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16-hour light to 8-hour dark photoperiod with a 30 minute transition period
- Light intensity: 470 and 640 Lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Immobility: observed after 24 and 48 hours of exposure
- Water Quality Criteria: At the start and at the end of the test, the pH values, the dissolved oxygen concentrations and the water temperature were determined in the single test concentration and the control. The appearance of the test medium was recorded at the start of the test and after 24 and 48 hours.

VEHICLE CONTROL PERFORMED: no

Reference substance (positive control):

yes

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Analytically determined concentration: The concentration of the test item in the test medium at the start and the end of the test was 96 mg/L of the nominal value, respectively. Under the conditions of the test, the test item was stable during the test period of 48 hours.
- Immobility: In the control and in the test concentration of 100 mg/L, no immobilized test organisms were observed during the test period of 48 hours.
- Appearance of the test medium: No remarkable observations were made concerning the appearance of the test medium. The test medium was a clear solution throughout the whole test duration.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: 48-hour EC50: 0.67 mg/L

Reported statistics and error estimates:

The NOEC and EC0 were determined directly from the raw data.
The EC50 and the EC100 could not be determined due to the absence of a toxic effect of the test item in this test.

The 48-hour NOEC (highest concentration tested without toxic effects after the exposure period of 48 hours) and the 48-hour EC0 of the substance to Daphnia magna were determined to be at least 100 mg/L. The 48-hour NOEC and the 48-hour EC0 might even be higher, but concentrations above 100 mg/L were not tested, in accordance with the test guidelines. The 48 -hour EC50 and the 48 -hour EC100 were clearly higher than 100 mg/L. These values could not be quantified due to the absence of toxicity of test item at the test concentration of 100 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

After exposure of Daphnia magna to test item over 48 hours in a limit test, the EC50 was determined to be > 100 mg/L.

Executive summary:

The acute toxicity of the test item to Daphnia magna was determined in a 48-hour static test according to OECD 202.

A limit test was performed in accordance with the test guidelines to demonstrate that the test item has no toxic effect on the test organisms up to and including a nominal concentration of 100 mg/L. Thus, the only nominal concentration tested was 100 mg/L in parallel to a control. The analytically measured concentration of the test item in the test medium was 96% at the start and at the end of the test.

The biological results were based on the nominal concentration of the test item.

In the control and in the nominal concentration of 100 mg/L, no immobilized daphnids were determined during the test period of 48 hours.

Therefore, the 48-hour NOEC (highest concentration tested without toxic effects after the exposure period of 48 hours) and the 48-hour EC0 of test item to Daphnia magna were determined to be at least 100 mg/L. The 48-hour NOEC and the 48-hour EC0 might even be higher, but concentrations above 100 mg/L were not tested in accordance with the test guidelines. The 48-hour EC50 and the 48-hour EC100 were clearly higher than 100 mg/L. These values could not be quantified, since the test item had no toxic effect on the daphnids up to 100 mg/L.

Description of key information

Two GLP studies are available.

A 48-hour static toxicity test was conducted in 2018 with the freshwater invertebrate, Daphnia magna, exposed to test item according to OECD 202. The 24- and 48-hour EC50 values were estimated to be >100 mg/L, the highest concentration tested. The 48 hour NOEC was 100 mg/L, the highest concentration tested.

Another acute toxicity of the test item to Daphnia magna was determined in a 48-hour static test according to OECD 202 in 2007. After exposure of Daphnia magna to test item over 48 hours in a limit test, the EC50 was determined to be > 100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L