1,3,4-Thiadiazole-2(3H)-thione, 5-(tert-dodecyldithio)-

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:

1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP guideline study on supporting substance. The definitive test concentrations exceeded the level of water solubility of the test substance. After addition and mixing of the test substance to the test chambers an oily surface film and yellow oily droplets were observed on the bottom of the test chembers. There was no analytical monitoring of test concentrations therefore the results are based on nominal concentrations. This result is read-across from ‘1,3,4-Thiadiazolidine-2,5-dithione, reaction products with hydrogen peroxide and tert-nonanethiol’. Read-across is justified as the two substances ‘1,3,4-Thiadiazolidine-2,5-dithione, reaction products with hydrogen peroxide and tert-dodecanethiol’ and ‘1,3,4-Thiadiazolidine-2,5-dithione, reaction products with hydrogen peroxide and tert-nonanethiol’ are virtually the same: the only difference between those two UVCB substances is that one of the used raw materials (alkanethiol) has a diversity in the C-range, i.e. on the one hand a tert. C12-alkanethiol is used in the manufacturing process, on the other hand a tert. C9. Hence, based on the (structural) similarity of both substances it is safe to say that the physicochemical, toxicological and ecotoxicological properties are likely to be similar.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

not specified

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,3,4-Thiadiazolidine-2,5-dithione, reaction products with hydrogen peroxide and tert-nonanethiol

EC Number:

293-927-7

EC Name:

1,3,4-Thiadiazolidine-2,5-dithione, reaction products with hydrogen peroxide and tert-nonanethiol

Cas Number:

91648-65-6

Molecular formula:

not applicable (UVCB substance)

IUPAC Name:

1,3,4-Thiadiazolidine-2,5-dithione, reaction products with hydrogen peroxide and tert-nonanethiol

Test material form:

liquid: viscous

Details on test material:

- Description: viscous amber liquid
- Storage condition of test material: ambient, dark

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No surrogate or analogue material was used.

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

- Nominal concentrations: 100, 180, 320, 560 and 1000 mg/L

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test compound was weighed directly into the test chambers. Before addition to the chambers, 1.5 mL of dimethylformamide (DMF) was added to each sample weight to increase the dispersion of the compound in the dilution water. The solvent control received an aliquot (1.5 mL) of DMF equivalent to that used in the test concentrations. After addition and mixing of the test compound into the test chambers, an oily surface film and large yellow oily droplets were observed on the bottom of all test chambers. The amount of surface film and the size of the droplet on the bottom increased with increasing test concentration. These observations were the same after 96-hours of testing.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): dimethylformamide
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): 0.01 %

Test organisms

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: Fathead minnow
- Source: in-house culture (Lot No. 485)
- Length at study initiation: 24 +/- 1.1mm
- Weight at study initiation: 0.20 +/- 0.034g
- Feeding during test: no

ACCLIMATION
- Acclimation period: 14 days
- Acclimation conditions: same as in the experimental part
- Type and amount of food: Standard commercial fish food (Rangen's)
- Feeding frequency: daily up until 48h prior to test initiation
- Health during acclimation: acclimation mortality reported as 1 %

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

No post exposure observation period described.

Test conditions

Hardness:

40 - 45 mg/L as CaCO3

Test temperature:

22 +/- 1 °C

pH:

7.1 - 7.8

Dissolved oxygen:

7.1 - 9.5 mg/L (82 % - 108 % saturation)

Salinity:

Not applicable.

Nominal and measured concentrations:

Nominal concentration
Range finding test: 1, 10 and 100 mg/L
Definitive test: 100, 180, 320, 560 and 1000 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 5 gallon glass vessels
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 1
- Biomass loading rate: approximately 0.13 g fish per litre

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: on-site well water
- Metals: aluminium < 0.010 ppm, arsenic < 0.0005 ppm, cadmium < 0.002 ppm, chromium < 0.006 ppm, cobalt < 0.003 ppm, copper < 0.002 ppm, iron < 0.004 ppm, lead 0.017 ppm, mercury 0.0008 ppm, nickel < 0.013 ppm, silver < 0.0004 ppm, zinc 0.001 ppm
- Pesticides: less than minimum detectable limits
- Alkalinity: 30-35 mg/L as CaCO3
- Intervals of water quality measurement: 0, 48, 96 h

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16h light/ 8h dark

TEST CONCENTRATIONS
- Spacing factor for test concentrations: logarithmic
- Test concentrations (Range finding study): 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: no mortalities at the highest concentration in the preliminary study therefore this was used as the lowest concentration in the definitive study

Reference substance (positive control):

yes

Remarks:

Antimycin A

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

NOELR

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Observations on body length and weight: length 24 +/- 1.1 mm and weight 0.20 +/- 0.034 g
- Other biological observations: none reported
- Mortality of control: none
- Other adverse effects control: none
- Abnormal responses: none
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: Not applicable since only nominal valuesare reported.

Results with reference substance (positive control):

- Results with reference substance valid: Yes
- Mortality: 100 % mortality at 48h
- LC50(96h): 53 ng/L

Reported statistics and error estimates:

LC50 values (for the positive control only) were calculated using either the binomial method or the probit method.

Any other information on results incl. tables

Sublethal observations / clinical signs:

Table 1: Results for the test Substance

Test Conc. mg/L	Mortality
	24h	48h	72h	96h
Control	0	0	0	0
Solvent control	0	0	0	0
100	0	0	0	0
180	0	0	0	0
320	0	0	0	0
560	0	0	0	0
1000	0	0	0	0
LL50(mg/L)	>1000	>1000	-	>1000

 

Table 2: Results for the Positive Control

Test Conc. mg/L	Mortality
	24h	48h	72h	96h
Control	0	0	0	0
Solvent control	0	0	0	0
0.000014	0	0	0	0
0.000024	0	0	0	0
0.000042	0	0	0	0
0.000075	2	10	-	-
0.00014	7	10	-	-
LL50(mg/L)	0.11 x 10^-5	5.6 x 10^-5	-	5.3 x 10^-5

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

Validity criteria were fulfilled.

Conclusions:

The test report describes a valid guideline study, conducted with GLP compliance. Based on the observed LL50 (equivalent to LC50) > 1000 mg/L, the test substance can be considered as non-toxic towards fish after an exposure time of 96 h.

Executive summary:

A study was performed to assess the acute aquatic toxicity of the supporting substance '1,3,4-Thiadiazolidine-2,5-dithione, reaction products with hydrogen peroxide and tert-nonanethiol' (CAS 91648-65-6). The method followed OECD Guideline 203, with the exception that the nominal concentrations were not measured analytically for confirmation. The preliminary 96 h acute toxicity study was conducted with the Fathead minnow at nominal test concentrations of 1, 10 and 100 mg/L. Ten fish per test concentration were used in the preliminary and the definitive study. In the definitive study test concentrations of 100, 180, 320, 560 and 1000 mg/L were tested. In parallel a control, a solvent control and a positive control group were tested. No mortality occurred at any of the test concentrations. Under the conditions of the test the LL50 at 96 hours exposure was determined to be > 1000 mg/L, whereat the result should be also applicable for the long-chain homologue '1,3,4-Thiadiazolidine-2,5-dithione, reaction products with hydrogen peroxide and tert-dodecanethiol' (no CAS#, no EC#).