Registration Dossier

Administrative data

Endpoint:
short-term toxicity to fish
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1984
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
publication
Title:
Acute toxicities of organic chemicals to fathead minnows (pimephales promelas), Vol 1
Author:
Brooke LT, Call DJ, Geiger DL, Northcott CE (eds)
Year:
1984
Bibliographic source:
Center for Lake Superior Studies, University of Wisconsin-Superior. ISBN 0-9614968-0-0

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: US EPA method E03-05
Deviations:
not specified
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Vehicle:
no

Test organisms

Test organisms (species):
Pimephales promelas
Details on test organisms:
TEST ORGANISM
- Common name: fathead minnows were cultured from brood stock
- Source: USEPA Environmental Research Laboratory (Duluth).
- Age at study initiation: Adults 32 day-old
- Length at study initiation: mean length of 18.6 mm (SD=2.393)
- Weight at study initiation: 0.106 g (SD=0.0385)
- Feeding:
- Food type: adult brine shrimp (Artemia). Fry were fed freshly hatched brine shrimp nauplii.
- Frequency: Fry were fed three times daily until 24-h before test start. Fish were not fed during exposure.
-other: held in a flow through system before use.

Study design

Test type:
flow-through
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h

Test conditions

Hardness:
45.5 mg/l as CaCO3. Measured using an EDTA method
Test temperature:
26.1 (SD=0.24) degC. Measured daily using a mercury thermometer. Target 25C.
pH:
7.75 (SD=0.1). Alkalinity 41.5 mg/l as CaCO3 by titration method.
Dissolved oxygen:
6.5 (SD=0.32) mg/l. Measured 3x during test using an O2 electrode.
Salinity:
not applicable
Nominal and measured concentrations:
1.3, 2.0, 3.1, 4.7 and 7.2 mg/l.

Details on test conditions:
TEST SYSTEM
- Material, size, headspace, fill volume: The tank volume was 1l
- No. of organisms per vessel: 20 fish
- Type of flow-through (e.g. peristaltic or proportional diluter): cycling proportional diluter (Mount, Water Res, 1, 21-9, 1967)
- Biomass loading rate: 1.409 g/l

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Lake Superior water
- Metals: Na~1.1mg/l; Ca~14mg/l; K~0.5mg/l; Mg~3mg/l; Al 1-26ug/l; Cr 2-20ug/l; Cu 0.3-3.2ug/l; Fe 2-83ug/l; Pb 7-20ug/l; Mn 0.2-11.5ug/l; Zn 1-2.7ug/l; Ni, Co<0.5ug/l; Cd<0.1ug/l
- Chloride: ~1.25 mg/l
- Ca/mg ratio:~28
- Conductivity: ~80umhos/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: results of measurements over a number of years (1980-83)

OTHER TEST CONDITIONS
- Photoperiod: 16 h light/dark photoperiod.
Reference substance (positive control):
no

Results and discussion

Effect concentrations
Duration:
96 h
Dose descriptor:
LC50
Effect conc.:
1.35 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Remarks on result:
other: 95% CI = 1.15 - 1.58
Details on results:
Fish continued to die even upon termination of the test (in the lowest exposure concentration).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
no data

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Conclusions:
In a well reported 96 hour acute toxicity study, fathead minnows (Pimephales promelas) were exposed to the test substance at concentrations up to 7.2 mg/l using a flow through method. An LC50 of 1.35 mg/l was established.