Benzene, mono-C10-13-alkyl derivs., distn. residues

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:

other: Acceptable well-documented study report which meets basic scientific principles.

Qualifier:

according to guideline

Guideline:

other: USEPA Method 2000.0, ASTM E729-96

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Test material was mixed with dilution water, in a ratio of 1 part test material to 9 parts dilution water, to produce a 100% WAF solution. The mixture was stirred for about 20 hrs in an Erlenmeyer flask with a vortex that was 25% the distance to the bottom of the flask. The flask was then sealed with a silicon or neoprene stopper. There was no headspace in the flasks. The mixture was allowed to settle for one hour, and the WAF near the bottom was then siphoned off for use in the test. Test solutions were renewed on day 2.

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: fathead minnow
- Feeding during test: no
- Source: in-house
- Age at study initiation (mean and range, SD): 4 days

ACCLIMATION
No

Test type:

semi-static

Total exposure duration:

96

Remarks on exposure duration:

h

Hardness:

92 mg/L CaCO3

Test temperature:

20 +/- 1 degree C

pH:

7.8-8.2

Nominal and measured concentrations:

Nominal: 0, 12.5, 25, 50, 100 % WAF

Details on test conditions:

TEST SYSTEM
- Test vessel: 500 ml glass jars
- Type: closed
- Renewal rate of test solution (frequency/flow rate): renewed at 48 hrs
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: prepared according to US EPA guidelines EPA-821-R-02-012

OTHER TEST CONDITIONS
- Photoperiod: 16 hrs light/8 hrs dark
- Light intensity: 50-100 ft candles


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Survival at 24, 48, 72, and 96 hrs

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 other: % WAF

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

2 fish in the control group were dead at the 96 hr observation. One fish in the % WAF test group died during the 48-hr renewal of the test substance. This mortality was not considered treatment related.

Sublethal observations / clinical signs:

Fish Mortality

Concentration  (% WAF)	24 hrs	48 hrs	72 hrs	96 hrs
0	20	20	20	18
12.5	20	20	20	20
25	20	19	19	19
50	20	20	20	20
100	20	20	20	20

Validity criteria fulfilled:

yes

Conclusions:

The 96-hr LC50 in fish is >100 % WAF.

Executive summary:

This study examined the acute toxicity of the test substance V-154L to fish. Duplicate groups of 10 fish were exposed to concentrations of 0, 12.5, 25, 50, 100 % water accommodated fraction (WAF) of test substance. Fish were exposed for 96 hrs, with the renewal of the test solution at 48 hrs. Fish were observed at 24, 48, 72, and 96 hrs for mortality. One fish in the 25% WAF exposure group died during renewal of the test solution. This death was not considered treatment related. All other fish in the exposure groups survived. The 96 -hr LC50 is > 100% WAF.

Description of key information

Two studies examined the acute toxicity of the HABs to fish. In the first study, duplicate groups of 10 fish were exposed to concentrations of 0, 12.5, 25, 50, 100 % water accommodated fraction (WAF) of the test substance. To produce the WAF, test material was mixed with dilution water in a ratio of 1 part test material to 9 parts dilution water, to produce a 100% WAF solution. The mixture was stirred for about 20 hrs in an Erlenmeyer flask with a vortex that was 25% the distance to the bottom of the flask. The flask was then sealed with a silicon or neoprene stopper. There was no headspace in the flasks. The mixture was allowed to settle for one hour, and the WAF near the bottom was then siphoned off for use in the test. Fish were exposed for a total of 96 hrs, with a renewal of the test solution at 48 hrs. Fish were observed for mortality and clinical signs at 24, 48, 72, and 96 hrs for mortality. One fish in the 25% WAF exposure group died during renewal of the test solution. This death was not considered treatment related. All other fish in the exposure groups survived. The 96 -hr LC50 is > 100% WAF.

The second study determined the toxicity of LAB  to fish in an extended acute study.  LAB is the most water soluble component of HAB. Fish were exposed for 14 days to a water accommodated fraction of 0, 5, 6.5, and 10 µg/L of test substance. The test medium was renewed daily. Fish were monitored daily for toxicity during the study for swimming behaviour, reaction to stimuli, discoloration, food intake, and mortality. All fish were weighed and measured before the test and survivors were weighed at test termination. No adverse effects were observed for the concentrations tested during the study period. A decrease in the test substance concentration was observed within 24 hours (day 1 and day 14), but the daily renewal of test solutions maintained the exposure to the test substance. Both the LOEC and NOEC were higher than the solubility concentration of >10 µg/L/day for this LAB, which as the most water soluble component of HAB demonstrates that HAB would not exhibit acute toxicity to fish at water soluble concentrations.