3-iodo-2-propynyl butylcarbamate

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1990-12-14 to 1991-02-08

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPP 72-4 (Fish Early Life-Stage and Aquatic Invertebrate Life-Cycle Studies)

Version / remarks:

1982

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: OECD 202

Version / remarks:

1984

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 9007 5747

Analytical monitoring:

yes

Details on sampling:

One-day prior to test initiation, water samples (approximately 1 L in volume) were collected from the low, middle and high test item containing test solutions to verify proper diluter function. Water samples were collected from the controls and each test item test solution on days 0, 7, 10, 14, 17 and 21 to monitor actual exposure concentrations. Water samples were collected from several diluter cycles prior to entry into the test system in order to collect the volume required for analysis. Samples were analyzed on the same day sampled.

Vehicle:

yes

Remarks:

DMF

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Test item stock solutions (5000 mg/L) were prepared daily by weighing approximately 0.0515 g of test item into a 10-mL volumetric flask and bringing to volume with DMF.
- Controls: vehicle and non-treatmtent control
- Chemical name of vehicle: DMF
- Concentration of vehicle in test medium: 80 µL/L in all test substance solutions and in solvent control
- Evidence of undissolved material: no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: Toxikon Environmental Sciences cultures established from animals originally received from the U.S. Environmental Protection Agency, Duluth, Minnesota
- Feeding during test: yes
- Food type: green alga and yeast/trout chow/cerophyll
- Frequency: daily

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

56 - 70 mg/L CaCo

Test temperature:

19.0 - 21.8 °C

pH:

The pH ranged from 7.4 to 8.1 in the dilution water control and from 7.4 to 7.9 in the solvent control. The pH ranged from 7.3 to 7.9 in all test item test solutions.

Dissolved oxygen:

Dissolved oxygen concentrations remained > 7.7 mg/L (> 85 percent of saturation) in the control, but were reduced by the presence of solvent in the solvent control and test item treatments which enhanced bacterial growth. Dissolved oxygen concentrations in the solvent control remained > 2.1 mg/L (> 23 percent of saturation), while those in the test item treatments remained > 1.2 mg/L ( > 13 percent of saturation).

Conductivity:

356 - 380 µmhos/cm

Nominal and measured concentrations:

nominal: 12.5, 25, 50, 100, 200 and 400 µg/L

Mean measured concentrations of test item ranged from 7.59 to 298 µg/L and from 50 to 74 percent of nominal. Seven representative stock solutions were also analyzed and the mean measured concentration was 5210 mg/L or 104 percent of nominal. Measured test concentrations were presumably low due to the presence of algae and bacteria to which the test item may have been adsorbed and subsequently removed by filtration prior to analysis.

Details on test conditions:

TEST SYSTEM
- Test vessel: 11.5 L glass tanks
- Type of flow-through: proportional diluter
- Renewal rate of test solution (frequency/flow rate): 250 mL per cycle; 3.4 cycles per hour; approx. 17 volume additions every 24 h
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: carbon-treated Jupiter, Florida, town water which was vigorously aerated prior to use
- Culture medium different from test medium: no
- Intervals of water quality measurement: test water quality was monitored periodically during the test. Water temperature was monitored hourly.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light and 8 hours dark; 15 min transition period
- Light intensity: approx. 333 - 408 lux

EFFECT PARAMETERS MEASURED:
Survival and reproduction of the water fleas was monitored daily and any dead removed. All young produced were counted and discarded. Any abnormalities in the behavior or physical appearance of the daphnids were also noted.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Range finding study: yes

Reference substance (positive control):

no

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

49.9 µg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

21 d

Dose descriptor:

other: MATC

Effect conc.:

> 49.9 - < 99.3 µg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Results with reference substance (positive control):

not applicable

Validity criteria fulfilled:

yes

Conclusions:

Chronic toxicity to water flea, daphnia magna, was studied under flow through conditions. NOEC was determined to be 49.9 µg/L

Executive summary:

A flow-through freshwater toxicity test was conducted to determine the chronic effects of the test item to water flea, Daphnia magna, with 21 d of exposure. Nominal concentrations of 12.5, 25, 50, 100, 200 and 400 µg/L were applied. The criteria for effect were first generation mortality, growth and reproduction (i.e., number of offspring produced). Results of the test are expressed as the maximum acceptable toxicant concentration (MATC). A MATC of 49.9 - 99.3 µg/L and a NOEC of 49.9 µg/L was determined.

Description of key information

Chronic toxicity to water flea, daphnia magna, was studied under flow through conditions. NOEC was determined to be 49.9 µg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

49.9 µg/L

Additional information

A flow-through freshwater toxicity test was conducted to determine the chronic effects of the test item to water flea, Daphnia magna, with 21 d of exposure. Nominal concentrations of 12.5, 25, 50, 100, 200 and 400 µg/L were applied. The criteria for effect were first generation mortality, growth and reproduction (i.e., number of offspring produced). Results of the test are expressed as the maximum acceptable toxicant concentration (MATC). A MATC of 49.9 - 99.3 µg/L and a NOEC of 49.9 µg/L was determined.