1-chloro-2,3-epoxypropane

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1982-12-1985-10

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study, although chemical analyses were absent the data of section 3.1.2 (Stability in water) indicate sufficient exposure.

Qualifier:

according to guideline

Guideline:

other: ASTM Standard E729-80

Deviations:

no

Remarks:

Not specified in report

Principles of method if other than guideline:

The main objective of this study was to determine the precision of daphnid acute tests within a laboratory while maintaining tight control over environmental and experimental factors that might have influenced test results. Thus replicated 48-h static acute tests were conducted to determine the toxicity of a number of chemicals including epichlorohydrin.

GLP compliance:

yes

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
not applicable

Analytical monitoring:

no

Details on sampling:

no analytical analysis was conducted

Vehicle:

not specified

Details on test solutions:

Stock solutions were prepared by dissolving the appropriate amount of the chemical in dilution water or acetone if a carrier was needed. All concentrations reported were nominal. Actual concentrations tested not stated in report.

Lake Huron water was used to culture and test daphnids. This water was obtained from the Midland Water Treatment Plant, Midland, Michigan prior to final chlorination and was adjusted to a hardness of approximately 170 mg/L as CaCO3. After adjusting harness, the daphnid dilution water was autoclaved at 121C and 124 kPa for 35 minutes. During this study, the means and standard deviations of the water quality variables were as follows: pH 8.0 +/-0.2, conductivity 311 +/-11 umhos/cm, hardness 157 +/-4 mg/L as CaCO3 and alkalinity 65 +/-4 mg/L as CaCO3.

Test organisms (species):

Daphnia magna

Details on test organisms:

Strain: Daphnia magna Straus 1820
- Source/supplier: not described
- Breeding method: the brood stock was maintained at 20 ± 1°C
and a light-dark cycle of 16h:8h
- Feeding: Selenastrum capricornutum three times a week (1.25
mg dry wt/L of dilution water)
- Pretreatment: 24 h before testing, multiparous females were
isolated and the neonates were used for testing
- Feeding during test: no
- Control group: yes

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

study was terminated after 48 hours

Hardness:

157 +/-4 mg/L as CaCO3

Test temperature:

19.8-20.9°C

pH:

7.7-8.3

Dissolved oxygen:

> 90% saturation

Salinity:

No data

Nominal and measured concentrations:

No data

Details on test conditions:

DILUTION WATER
- Source: Lake Huron water
- Alkalinity: 65 ± 4 mg/l as CaCO3
- Hardness: 157 ± 4 mg/l as CaCO3
- pH: 8.0 ± 0.2
- Conductance: 311 ± 11 µmhos/cm
TEST SYSTEM
- Test type: static without renewal of test solution and
without aeration
- Concentrations: not described
- Exposure vessel type: 200 ml test solution in a 250 ml
glass beaker
- Number of replicates, individuals per replicate: 3/10
- Test temperature: 19.8-20.9°C
- Dissolved oxygen: > 90% saturation
- pH: 7.7-8.3
- Intensity of irradiation: 970-1250 lumens per m2
- Photoperiod: 16h:8h light-dark cycle
TEST PARAMETER: immobility of test organisms

Reference substance (positive control):

not specified

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

23.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL: 19.4-32.9 mg/L

Details on results:

Three separate studies were conducted within the laboratory. The calculated EC50 was 28.9, 22.6 and 21.0 mg/L for each study. The geometric mean of the 3 values was 23.9 mg/L.

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

not applicable

The 48 hr EC50 in daphnids was determined in 3 separate studies of epichlorohydrin. The EC50 for each study was similar with the highest value at 28.9 mg/L while the lowest was 21.0 mg/L. The geometric mean of the 3 values was 23.9 mg/L.

Validity criteria fulfilled:

yes

Remarks:

he control mortality was below the validity criterion.

Conclusions:

A 48h EC50 value of 23.9 mg/l with 95% confidence intervals of 19.4-32.9 mg/l was found.

Executive summary:

The 48 hr EC50 in daphnids was determined in 3 separate studies of epichlorohydrin. The EC50 for each study was similar with the highest value at 28.9 mg/L while the lowest was 21.0 mg/L. The geometric mean of the 3 values was 23.9 mg/L.

Description of key information

The 48-hour EC50 value of 23.9 mg/L for epichlorohydrin is the geometric mean calculated from three 48-hour EC50 values reported in a valid exposure study with Daphnia magna.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

23.9 mg/L

Additional information

One acute toxicity test with Daphnia magna was assessed for this endpoint. This study was deemed of good quality and useful for risk assessment (Klimish score = 2). In this study, a series of three acute exposures with epichlorohydrin were conducted with D. magna and three 48-hour EC50 values (based on immobility) were calculated. The calculated EC50 values were 28.9, 22.6 and 21.0 mg/L epichlorohydrin. The geometric mean of the three values was 23.9 mg/L epichlorohydrin, and this value was selected as the key parameter for this endpoint.