4-[trans-4-(trans-4-butylcyclohexyl)-cyclohexyl]-1-ethoxy-2, 3-difluorobenzene

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

Study period:

from 2011-07-29 to 2011-09-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: METI Guideline: Concentration Test on Chemical Substances in Fish

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 305 (Bioconcentration: Flow-through Fish Test)

Deviations:

no

Principles of method if other than guideline:

SPAN 20 used as solubilizer

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch: E011009938

Radiolabelling:

no

Details on sampling:

- Sampling intervals/frequency for test organisms: days 0, 7, 14, 21, 26, 28
- Sampling intervals/frequency for test medium samples: days 0, 7, 14, 21, 26, 28
- Details on sampling and analysis of test organisms and test media samples (e.g. sample preparation, analytical methods):
Water: Extraction with CH2Cl2 with further HPLC analysis.
Fish: two fish per sampling homogenised, and extracted with acetonitril/n-hexane. The analysis was performed using HPLC.

Vehicle:

yes

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

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Tween 80 / SPAN 80 = 3 / 1
- Concentration of vehicle in test medium (stock solution and final test solution(s) at different concentrations and in control(s)): 0.024 and 0.024 mg/l
Dose 1: Test item: 0.008 mg/L , Vehicle: 0.024 mg/L
Dose 2: Test item: 0.0008 mg/L , Vehicle: 0.0024 mg/L
Vehicle Control: test item: - , Vehicle: 0.024 mg/L

Test organisms (species):

Cyprinus carpio

Details on test organisms:

Weight: 3.07 +/- 0.23 g
Length: 6.70 +/- 0.20 cm
Lot: 110419
Date: 2011-04-19

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

28 d

Test temperature:

26.4 ° +/- 0.5 °C

pH:

7.7 +/- 0.0

Dissolved oxygen:

7.4 +/- 0.1 mg/L

Salinity:

According to guideline

Details on test conditions:

After acclimatisation period, the fish (Cyprinus carpio) were transferred into the test media under flow through conditions. Exposure concentrations were analytically verified at days 0, 7, 14, 21, 26 and 28. The analytical values show that the nominal concentrations of 0.008 and 0.0008 mg/L were maintained at about 100% using solubiliser, respectively. At days 0, 7, 14, 21, 26 and 28 two fish each were removed from each test group. Body weight was determined. The fish were homogenised and extracted using organic solvents. The extract was analysed with HPLC. Due to the low bioaccumulation potential, no depuration phase was required.

Nominal and measured concentrations:

nominal concentration 0.008 mg/L:
analytically measured concentrations:
day 0: 0.00799 mg/L;
day 7: 0.00788 mg/L;
day 14: 0.00780 mg/L
day 21: 0.00792 mg/L
day 26: 0.00788 mg/L
day 28: 0.00797 mg/L

nominal concentration 0.0008 mg/L
analytically measured concentrations:
day 0: 0.000776 mg/L
day 7: 0.000775 mg/L
day 14: 0.000764 mg/L
day 21: 0.000781 mg/L
day 26: 0.000778 mg/L
day 28: 0.000784 mg/L

Details on estimation of bioconcentration:

according to guideline

Key result

Conc. / dose:

0.008 mg/L

Temp.:

24.7 °C

pH:

7.7

Type:

BCF

Value:

130 dimensionless

Basis:

normalised lipid fraction

Time of plateau:

14 d

Calculation basis:

steady state

Key result

Conc. / dose:

0.001 mg/L

Temp.:

24.7 °C

pH:

7.7

Type:

BCF

Value:

123 dimensionless

Basis:

not specified

Time of plateau:

14 d

Calculation basis:

steady state

Details on kinetic parameters:

Steady state was reached within 14 days
Due to the low uptake, no depuration phase was necessary

Details on results:

- Mortality of test organisms: no effects
- Behavioural abnormalities:no effects
- Observations on body length and weight:no effects
- Other biological observations: no effects
- Bound residues forming a plateau: no
- Mortality and/or behavioural abnormalities of control: no
- Loss of test substance during test period: no
- Results with vehicle control: no effects

Validity criteria fulfilled:

yes

Conclusions:

The test material showed no relevant bioaccumulation at concentrations at or above the water solubility. The steady state BCF values were at 130 and 123 (mean 126). The test material showed no relevant bioaccumulation (BCF < 2000).

Description of key information

Aquatic bioaccumulation of ECHA Substance was investigated in a flow-through system set up according to OECD guideline 305. The study was performed using solubilizer to achive maximum exposure. A BCF of 130 at a concentration of 8 μg/L was detected whereas at a concentration of 0.8 μg/l the BCF was 123 giving a mean steady state BCF of 126. Therefore it can be considered that the substance does not bioaccumulate in organisms after 28 days exposure via the aqueous phase.

Key value for chemical safety assessment

BCF (aquatic species):

126 dimensionless