Registration Dossier

Administrative data

Endpoint:
long-term toxicity to fish
Type of information:
experimental study
Adequacy of study:
key study
Study period:
February 10, 2000- March 2, 2000
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report Date:
2000

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: OECD Guideline 203
Deviations:
yes
Remarks:
Study was extended to 21 days
GLP compliance:
not specified
Remarks:
(Not stated, but appears to be conducted similar to GLP studies)

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Sample storage conditions before analysis: samples were analyzed immediately and processed within 2 hrs, analytical standards were kept in acetonitrile at 0-4 degrees C.

Test solutions

Vehicle:
yes
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 40 uL of test compound was dissolved in 22 mL of acetone. 356 mL of MilliQ water was then added. The solution was pumped into a premix flask. Fresh stock solution was prepared daily.
- 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 mg/L

Test organisms

Test organisms (species):
Danio rerio (previous name: Brachydanio rerio)
Details on test organisms:
TEST ORGANISM
- Common name: zebra fish
- Source: Agrojardin, Avda. Cantabria 4, San Sebastian de los Reyes, 28050 Madrid, Spain
- Length at study initiation (length definition, mean, range and SD): 2 +/- 1 cm
- Feeding during test
- Food type: Nutrafin
- Amount: 2% mean bodyweight
- Frequency: once every three days

ACCLIMATION
- Acclimation period: 14 days
- Acclimation conditions (same as test or not): water temperature, photoperiod and feed were similar to those in test
- Type and amount of food: Nutrafin, 10% of bodyweight
- Feeding frequency: once a day every working day
- Health during acclimation (any mortality observed): no mortality observed

Study design

Test type:
flow-through
Water media type:
not specified
Limit test:
yes
Total exposure duration:
21 d

Test conditions

Hardness:
49.52-60.95 mg CaCO3/L; determined twice weekly
Test temperature:
20 +/- 1 degree C; determined daily
pH:
6.33-7.41; determined twice weekly
Dissolved oxygen:
44-85.8% of saturation; determined twice weekly
Nominal and measured concentrations:

Measured: 57.78 +/- 31.85 ng/ml (equivalent to 57.78 ug/L)
Details on test conditions:
TEST SYSTEM
- Test vessel: aquaria
- Material, size, headspace, fill volume: glass, 40 cm x 25 cm x 20 cm, 15 L
- Aeration: dilution water tank was aerated with oil-free air; exposure tanks were not aerated
- Type of flow-through (e.g. peristaltic or proportional diluter): peristaltic
- Renewal rate of test solution (frequency/flow rate): 1.32 L/hr
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 10


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Madrid tap water, dechlorinated using sodium thiosulphate, purified with charcoal
- Nitrites: 0.003-0.070 mg NO2-
- Conductivity: 142.6-213 uS/cm
- Intervals of water quality measurement: every 3-4 days

OTHER TEST CONDITIONS
- Photoperiod: 12 hrs light/12 hrs dark

EFFECT PARAMETERS MEASURED: mortality, behaviour and toxic symptoms

TEST CONCENTRATIONS
- Test concentrations: acetone was used as a vehicle to obtain a testing concentration above the water solubility (37.2 +/- 11.7 ng/mL) of LAB. Note that all concentrations in the study are reported in units of ng/mL, which is equivalent to ug/L. The standard units for aquatic toxicity data are ug/L and so these units are used to report the results in this summary.
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
57.78 µg/L
Nominal / measured:
meas. (initial)
Conc. based on:
test mat.
Basis for effect:
other: behaviour, toxic symptoms, mortality
Remarks on result:
other: no toxic effects observed
Duration:
21 d
Dose descriptor:
other: CL0
Remarks on result:
other: above water solubility limit
Details on results:
No mortality was observed in the test substance aquarium. One incidental non-treatment related mortality was observed in the control group. Another fish was removed from the control group due to attack by other fish. No toxic symptoms were observed in any of the test aquaria. Note that individual homologues were also tested. Phenyl C10, C12 and C18 also resulted in no toxic symptoms for the duration of the study.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The 21-day NOEC zebra fish exposed to LAB is 57.78 ug/L. The CL0 is above the water solubility limit.
Executive summary:

Two groups of ten zebra fish were exposed in an extended acute test to a test solution of LAB for 21 days, where the LAB concentration was at or above the water solubility limit. This high concentration was obtained by using acetone as a vehicle. The measured test concentration was 57.78 ug/L, above the water solubility of 37.2 ug/L determined in a water solubility test conducted concurrently. No mortality, behavioural changes, or toxic symptoms were noted in the exposure groups. The 21 -day NOEC for zebra fish is 57.78 ug/L, the CL0 is above the water solubility limit of LAB.