Thiosemicarbazide

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

OECD 203

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: The Notice on the Test Method Concerning New Chemical Substances

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

not specified

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:Test solutions were prepared by mixing a stock solution of the test substance, which was prepared by dissolving the substance in test water.

Test organisms (species):

Oryzias latipes

Details on test organisms:

FEEDING DURING TEST: No

Test type:

static

Water media type:

other: dechlorinated tap water

Limit test:

no

Total exposure duration:

96 h

Test temperature:

23.1-24.0ºC

Nominal and measured concentrations:

Nominal : 60, 38, 23, 15, 9.2 mg/L, control

Details on test conditions:

TEST SYSTEM
- Material, size, headspace, fill volume: test solution volume ca. 5 L/concentration
- Aeration: Yes
- No. of organisms per vessel:7/concentration
- No. of vessels per concentration (replicates):1

OTHER TEST CONDITIONS
- Photoperiod: Room light
- Light intensity:16 hours light / 8 hours dark

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.6

Reference substance (positive control):

not specified

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 21 mg/L

Nominal / measured:

nominal

Conc. based on:

not specified

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL = 17 - 27 mg/ l

Details on results:

All results were based on the nominal values.

Validity criteria fulfilled:

not specified

Conclusions:

Test item has value of lethal concentration LC50 (96h) of 21 mg/L. (Acute toxicity on fish)

Executive summary:

Based on available data from National instititute of technology and evaluation (NITE) test item was tested for acute toxicty on fish ( Oryzias latipes) in the nominal concentration : 60, 38, 23, 15, 9.2 mg/L at the temperature 23.1-24.0ºC according the OECD guideline 203, followed GLP principles. Test animals were alocated in the vessels,seven organism per vessels/concentration. Test was performed as the static test for 96 hours. Test solutions were prepared by mixing a stock solution of the test substance, which was prepared by dissolving the substance in test water.The Lethal concentration LC50 (96h) of 21 mg/L was evaluated.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

other: U.S.E.P.A. (U.S. Environmental Protection Agency), 1975. Methods for Acute Toxicity Tests with Fish, Macroinvertebrates, and Amphibians.

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

In the study were used 5 fish per vessel and in the TG 203, at least 7 fish must be used.

GLP compliance:

not specified

Analytical monitoring:

yes

Details on sampling:

Water samples taken at the beginning and end of each test were analyzed for toxicant concentration.All water samples were filtered through 0.45-pm filters before analysis.

Vehicle:

not specified

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Strain:Fathead minnow
- Source: E.P.A. Newtown Fish Toxicology Station, Cincinnati, Ohio

ACCLIMATION
- Acclimation period:4 days
- Acclimation conditions (same as test or not):Yes

Fish were observed for a minimum of 14 days before testing.Only healthy populations were used.

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Hardness:

40-48 mg/L hardness as CaCO3

Test temperature:

22+-1ºC

pH:

7.2-7.9

Conductivity:

120-160 uS/cm

Details on test conditions:

TEST SYSTEM
- Test vessel: Bioassay container -Aquarium
- Material, size, headspace, fill volume: 121 l of dilution water, depth =24 cm
- Aeration: Stirring
- Renewal rate of test solution (frequency/flow rate): No
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates):2. For each chemical, at least five concentrations were tested.
- No. of vessels per control (replicates):2 with 5 organism in each vessel.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted soft water of the following quality was used:
- Alkalinity:30-35 mg/1 alkalinity as CaCO3
- Hardness: 40--48mg/1 hardness as CaCO3
- Conductivity:120--160/~S/cm conductivity
- pH: 7.2--7.9.
- Intervals of water quality measurement: At the start and end of the test.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : During the 96-hr. test period, deaths were recorded and bodies removed whenever noticed. After each 24-hr. period, the number of organisms surviving, dissolved oxygen, and temperature were determined in each aquarium.It was of particular interest to monitor dissolved oxygen throughout the test period, since many toxicants exerted severe biochemical oxygen demands. At the end of the test period, pH was measured and another water sample was withdrawn for toxicant analysis. The control organisms were then weighed and measured to determine the average size of the test organisms.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 0.6

Reference substance (positive control):

not specified

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 20.8 mg/L

Nominal / measured:

not specified

Conc. based on:

not specified

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence interval = 15.7-29.3mg/L

Details on results:

- Mortality of control:Control mortality was less than 10% in every case.

Reported statistics and error estimates:

Toxicant determination methods used in analyses of bioassay solutions :Relative error 13.1, SD:+-13.9,procedure developed at Rice University;Jacob and Nair (1966). 96-hr. LC50 and 95% confidence limits were calculated using either the probit, moving average, or binomial test method, depending on the number of partial kills observed. Two or more partial kills were subjected to computer probit analysis (Barr, 1976) or to moving average calculations using an American Society for Testing and Materials Subcommittee E35.21 computer program (January 1978 version, unpublished).The binomial test (AB 1/2 = LC50) was used for data having less than two partial kills (Stephan, 1977).A represents the highest concentration which produced zero mortality, and B represents the lowest concentration which produced 100% mortality.A and B were taken as conservative 95% confidence limits - It represented the range of sensitivities of the test organisms.

Validity criteria fulfilled:

not specified

Conclusions:

The LC50 (96h) for Thiosemicarbazide is 20.8 mg/L, tested on species Pimephales promelas in static conditions.

Executive summary:

The test item was tested for the toxicity to fish species Pimephales promelas. Test was performed in static conditions during 96 hour in freshwater. Fish were tested in quarium where the test ítem was added directly or in the form of a stock solution in deionized water. Five organisms were then placed in each of two duplicate aquaria (ten organisms per concentration). For each chemical, at least five concentrations were tested in a 0.6 geometric series. Two control aquaria, containing a total of ten organisms, were run with each test series. Control mortality was less than 10% in every case. The observed paramater in this study was LC50 (96h) with value of 20.8 mg/l and 95% confidence interval of 15.7-29.3mg/L.To the tested substance was assigned degree of toxicity acoording the E.P.A. : category C.

Description of key information

Weight of evidence: Guideline TG 203, GLP principles followed. Based on available data from National instititute of technology and evaluation (NITE) test item has Lethal concentration LC50 (96h) of 21 mg/L, tested on the fish: Oryzias latipes.The result of the study, published in the Journal of Hydrology, is evaluated as LC50 (96h) of 20.8 mg/L and 95% confidence interval of 15.7-29.3mg/L, tested on the fish species Pimephales promelas. To the tested substance was assigned the degree of toxicity according the E.P.A., category C.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

20.8 mg/L

Additional information

Weight of evidence: Based on available data from National instititute of technology and evaluation (NITE) test item was tested according the OECD TG 203, followed GLP principles for acute toxicty on fish, species Oryzias latipes. Test was performed in static conditions, in the nominal concentration : 60, 38, 23, 15, 9.2 mg/L and at the temperature 23.1-24.0ºC, for 96 hours. Test animals were alocated in the vessels,seven organism per vessels/concentration. Test solutions were prepared by mixing a stock solution of the test substance, which was prepared by dissolving the substance in test water.The Lethal concentration LC50 (96h) of 21 mg/L was evaluated. According the study published in the Journal of Hydrology,test item was tested for the toxicity to freswater fish species Pimephales promelas.The test was performed in static conditions during 96 hours.Fish were tested in aquarium filled with water and test item which was added directly or in the stock solution. Five concentrations were used with factor 0.6. The result of this study is LC50 (96h) OF 20.8 mg/L and 95% confidence interval of 15.7-29.3mg/L. To the tested substance was assigned the degree of toxicity according the E.P.A., category C.