Benzene, C10-13-alkyl derivs.

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

other: ASTM Committee E-35.21

GLP compliance:

no

Radiolabelling:

yes

Details on sampling:

- Sampling intervals/frequency for test organisms: 2, 4, 8, 12, 24, 48, 72, and 96 hrs in the uptake phase, and 2, 4, 8, 24, 48, 72, and 96 hrs in the depuration phase
- Sampling intervals/frequency for test medium samples: 2, 12, 24, 48, 72, and 96 hrs in the uptake phase, and every 24 hrs in the depuration phase
- Details on sampling and analysis of test organisms and test media samples (e.g. sample preparation, analytical methods): Test medium - Duplicate samples of 10 ml were added to 10 ml scintillation fluid and counted for 10 minutes. For fish, at each sampling time, 3 fish were collected, except for the final sampling at which all fish were collected. The fish were dissected into gall bladder, viscera, and remainder. The samples were frozen, homogenized with dry ice, then sublimed and combusted. These tissue homogenates of, ~750 mg, were analyzed using scintillation counting in triplicate.

Vehicle:

yes

Details on preparation of test solutions, spiked fish food or sediment:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Stock solution was 245 mg/L test substance.
- Controls: yes
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): acetone

Test organisms (species):

Lepomis macrochirus

Details on test organisms:

TEST ORGANISM
- Weight at study initiation (mean and range, SD): 6 g
- Feeding during test
- Food type: Rangen's commercial fish food
- Amount: 3% of bodyweight
- Frequency: daily

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

96 h

Total depuration duration:

96 h

Hardness:

255 mg/L CaCO3

Test temperature:

21-22 degree C

pH:

7.6-8.3

Dissolved oxygen:

6.9-9.1 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 100 liter glass aquaria
- Aeration: aerated well-water
- Type of flow-through (e.g. peristaltic or proportional diluter): proportional diluter
- Renewal rate of test solution (frequency/flow rate): 350 ml/min.
- No. of organisms per vessel: 150
- No. of vessels per concentration: 1
- No. of vessels per control / vehicle control: 1 (vehicle control)


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: aerated well water

Nominal and measured concentrations:

- 0.1 mg/L nominal,
- 0.092 mg/L measured

Reference substance (positive control):

not specified

Remarks on result:

other: not reported

Key result

Conc. / dose:

0.092 mg/L

Temp.:

>= 21 - <= 22 °C

Type:

BCF

Value:

35 L/kg

Basis:

whole body w.w.

Time of plateau:

48 h

Calculation basis:

steady state

Key result

Parameter:

DT50

Depuration time (DT):

2 d

Details on kinetic parameters:

- Uptake rate constant (k1): 12 L/mg/day
- Depuration (loss) rate constant (k2): 0.34/day
- Computation / data analysis: BIOFAC Method

Details on results:

- Bioconcentration factor calculated based on octanol/water partitioning was 6250-6600. The much smaller actual measured value is due to the substance being metabolized and eliminated.

Steady state concentration was reached by 48 hrs. Tissues concentrations at 96 hrs were 115 µg/g in the gall bladder, 7.1 µg/g in the viscera, and 1.3 µg/g in the remainder of the fish.

Validity criteria fulfilled:

yes

Conclusions:

The bioaccumulation factor in fish was 35.

Executive summary:

This study examined the bioaccumulation of linear alkylbenzenes in fish. 150 bluegill fish were exposed to 0.092 mg/L solution of test substance for 96 hrs (flow-through test). 3 fish were taken for sampling at 2, 4, 8, 12, 24, 48, 72, and 96 hrs after start of exposure. A steady state concentration in fish was reached at 48 hrs. Samples were analyzed using liquid scintillation counting. During the depuration phase, the fish were sampled at 2, 4, 8, 24, 48, 72, and 96 hrs. An additional 150 fish were exposed to vehicle (acetone) only. The bioaccumulation factor in fish was 35.

Description of key information

The BCF was 35. The bioconcentration factor in fish was determined using the ASTM E-35.21 guideline.  

Key value for chemical safety assessment

BCF (aquatic species):

35 dimensionless

Additional information

The study examined the bioaccumualion of the substance in fish. A total of 150 bluegill sunfish were exposed to 0.092 mg/L substance for 96 hours in a flow through apparatus. Three fish were sampled at several points during the study and analyzed for the substance in the tissues. A steady state concentration was reached at 48 hours and additional fish were sampled during a depuration period.