Zinc bis(diethyldithiocarbamate)

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

GLP-compliance, EPA guideline study, available as unpublished report, minor restrictions, adequate for assessment.

Qualifier:

according to guideline

Guideline:

other: Committee on Methods for Toxicity Tests with Aquatic Organisms (C. E. Stephan, Chairman). 1975. Methods for Acute Toxicity Tests with Fish, Macroinvertebrates and Amphibians. Environmental Pro tection Agency, Ecological Research Series EPA-660/3-75-009

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:
Test concentrations were prepared based on the total compound. The test concentrations were obtained by transferring appropriate aliquots of work stock directly to the test chambers. The solvent control received an aliquot (5.0 ml) of acetone equivalent to that used in the highest test concentration. The working solution was prepared in nanograde acetone.
- Controls: Yes
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Acetone
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): 100% pur acetone solvent (stock solution) and 26 mg/l (final test solution) on solvent control and the highest test concentration.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Source: Spring Creek Trout Hatchery in Lewistown, Montana.
- Lot number: ABC lot #2183
- Length of control group at test termination (length definition, mean, range and SD): 41 (±3.6) mm
- Weight of control group at test termination (mean and range, SD): 1.2 (±0.33) g

ACCLIMATION
- Acclimation period: 48 hours
- Acclimation conditions: same as test
- Type and amount of food: without food
- Health during acclimation (any mortality observed): no death

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

255 ppm as CaCO3

Test temperature:

12°C (± 1.0)

pH:

8.0 - 8.2

Dissolved oxygen:

7.0 - 8.7 mg/l

Salinity:

Not applicable

Nominal and measured concentrations:

- Nominal concentrations: 0.10, 0.18, 0.32, 0.56 and 1.0 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: gallon glass vessels
- Material, size, headspace, fill volume: 15 liters of solution
- No. of organisms per concentration: 10
- No. of vessels per concentration (replicates): duplicates

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Well Water at ABC’s Aquatic Bioassay Laboratory (for composition see below)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: concentrations ranging in a logarithmic series from 0.10 to 1.0 mg/l
- Range finding study
- Test concentrations: 0.10, 1.0 and 10 mg/l

Reference substance (positive control):

yes

Remarks:

Antimycin A

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.23 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 0.18-0.32 mg/l

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

0.32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 0.18-0.56 mg/l

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

0.42 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 0.32-0.56 mg/l

Details on results:

- Behavioural abnormalities: The abnormal effects of mortality, surfacing, loss of equilibrium, dark discoloration and fish on the bottom progressed from 1.0 mg/l initially to 0.18 mg/l after 96 hours.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- LC50 (96h): 3.2x10E-5 mg/l (within the 95% confidence intervals reported in the literature)

Sublethal observations / clinical signs:

Mortality rates during the acute toxicity test of Ethasan to Rainbow Trout (Salmo gairdneri)

	Percent mortality hours
Concentration (mg/l)	24 hours	48 hours	96 hours
Control	0	0	0
Solvent control	0	0	0
0.10	0	0	0
0.18	0	0	10
0.32	0	50	100
0.56	100	100	100
1.0	100	100	100

NOTE: Dissolved oxygen saturation at the test temperature of 12°C is 10.8 mg/l.

Description of key information

The 96-h LC50 of 0.23 mg/L in Oncorhynchus mykiss (tested as Salmo gairdneri) is used in the assessment.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.23 mg/L

Additional information

Four short-term toxicity studies with freshwater fish are available for zinc diethyldithiocarbamate. A GLP-compliant, EPA-660/3-75-009 guideline study with the rainbow trout (Oncorhynchus mykiss tested as Salmo gairdneri) is available (Analytical Bio-Chemistry Laboratories, Inc., 1983a). The test is static without analytical monitoring. The 96-h LC50 value is 0.23 mg/L.

Another study is available with the fathead minnow (Pimephales promelas)(Analytical Bio-Chemistry Laboratories, Inc., 1983b). The study is a static GLP-compliant, EPA-660/3-75-009 guideline study without analytical monitoring. The 96-h LC50 value is 0.26 mg/L.

A third study is available with the bluegill sunfish (Lepomis macrochirus)(Analytical Bio-Chemistry Laboratories, Inc., 1983c). The study is a static GLP-compliant, EPA-660/3-75-009 guideline study without analytical monitoring. The 96-h LC50 value is 0.4 mg/L.

A fourth study is conducted with the guppy Poecilia reticulata (van Leeuwen, et al., 1985a; van Leeuwen, 1986). The study is a semi-static non-GLP, OECD 203 guideline study without analytical monitoring. The 96-h LC50 value is 0.75 mg/L.

The study with Oncorhynchus mykiss (tested as Salmo gairdneri) is the most critical study and will therefore be used in the assessment.