Piperidine-4-carbothioamide

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 6.25 mg/L and 100 mg/L at 0 and 48 hours
- Sample storage conditions before analysis: Routinely, the samples were analysed immediately. Only in exceptional cases, they were stored overnight deep frozen and protected from light.

Vehicle:

no

Details on test solutions:

PRETREATMENT OF TEST ITEM:
- A stock solution was prepared to give the desired series of test concentrations. 99.8 mg of the test item were added to 1 litre of dilution water, treated for 1 h in an ultrasonic bath and stirred for 1 h on a magnetic stirrer. The pH was measured to be 9.4 and was adjusted to
pH 8.1.
- To produce the different test item concentrations appropriate amounts of the stock solution were diluted with dilution water to a volume of 500 mL. 50 mL of the prepared solutions were taken per replicate and 0.5 mL of dilution water containing 5 daphnids was given to all replicates resulting in the final nominal concentrations. For each test item concentration and the control 4 replicates were prepared.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna STRAUS, parthenogenetic females
- Source: Strain of Bundesgesundheitsamt Berlin

ACCLIMATION
- A population of parthenogenetic females of synchronized age structure has been maintained for more than 20 years in the test facility under constant temperature conditions (20 +/- 2 °C) at a 16 : 8 hour light-dark photoperiod (light intensity: < 20 μE x m-2 x s-1). The culture water (so-called 'M4 medium') was partly renewed once a week. The Daphnia were exclusively fed unicellular green algae (Desmodesmus subspicatus) 'ad libitum'. Mortalities of parent Daphnia during the culture period were recorded daily. The neonates were separated from their parent Daphnia by filtration prior to the acute test.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

14.5 °dH (= 259 mg/L CaCO3)

Test temperature:

20.1 - 20.8 °C at start, 19.7 °C at end

pH:

7.8 - 8.1 at start, 7.9 - 8.0 at end

Dissolved oxygen:

8.4 - 9.2 mg/L at start, 8.8 - 9.4 mg/L at end

Nominal and measured concentrations:

6.25, 12.5, 25, 50 and 100 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass beakers covered with watch glasses
- Type: closed
- Material, size, headspace, fill volume: 5 neonates in 50 mL of test medium
- Aeration: none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Feeding: no feeding during the exposure period
- Method of initiation : neonates were placed in prepared media
- Temperature of incubation unit : 19.5 to 19.7 °C

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water (so-called 'M4 medium' according to OECD 202 and EC Method C.2, annex 1)

OTHER TEST CONDITIONS
- Photoperiod: 16 h light : 8 h dark
- Light intensity: < 20 μE x m-2 x s-1

RANGE-FINDING STUDY
- Test concentrations: 1, 10 and 100 mg/L

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Effective concentrations ranged from 101.5 % to 101.6 % of nominal values at 0 hours and from 98.0 % to 99.0 % of nominal values at 48 hours.
- The results are expressed in terms of geometric mean measured concentrations.

The EC 50 was calculated by probit analysis using the statistics programme ToxRatPro Version 2.10 (released 2010-09-10).

Validity criteria fulfilled:

yes

Remarks:

(immobilisation and other abnormalities in the controls did not exceed 10 % by the end of the test; dissolved oxygen concentration remained above 3 mg/L throughout the exposure period)

Conclusions:

For Piperidine-4-carbothioamide an EC 50 (48 h) of 100 mg/L was observerd.

Executive summary:

In accordance with the Council Regulation (EC) No 440/2008, Method C.2 ‘Acute toxicity for Daphnia’ (2008) a study was performed to assess the acute toxicity of the test substance to Daphnia magna STRAUS under static conditions. A range finding test preceded the main test. It provided information about the range of concentrations which were used in the main test. The following nominal concentrations of the test item were tested in the range finding test: 1, 10 and 100 mg/L. In the main test Daphnia were exposed to the test item added to dilution water at a range of concentrations ( 6.25, 12.5, 25, 50 and 100 mg/L) for a period of 48 hours. Defined concentrations of test substance led to a certain percentage proportion of immobilised Daphnia at the end of the 48 hour study period. Immobilisation rates were recorded at 24-hour intervals. The EC 50 was calculated by probit analysis using the statistics programme ToxRatPro Version 2.10 (released 2010-09-10). Additionally any abnormal behaviour or appearance of the Daphnia was reported. The main test was conducted as a static test with the test medium unchanged throughout the duration of the test. During the test a temperature range of 18 - 22 °C was maintained in the test vessels, with a maximum temperature fluctuation of +/- 1 °C in each individual test. The temperature, the pH and the oxygen values were measured at the beginning and end of the test. Observations were made on the swimming ability and the immobilisation rate, respectively, after 24 and 48 hours of exposure.

For the test substance an EC 50 (48 h) of 100 mg/L was observerd.

The results are expressed in terms of nominal concentrations. Effective concentrations ranged from 85.1 % to 90.3 % of nominal values at 0 hours and from 85.0 % to 88.5 % of nominal values at 48 hours.

Description of key information

For the test substance an EC 50 (48 h) of 100 mg/L was observerd.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L