2,3-Difluor-1-propoxy-4-[trans-4-(trans-4-propylcyclohexyl)- cyclohexyl]-benzene

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 2007-12-12 to 2008-03-17

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:

Tween 80 used as solubilizer

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch: L57020431

Radiolabelling:

no

Details on sampling:

- Sampling intervals/frequency for test organisms: days 0, 7, 14, 21, 23, 28, 30
- Sampling intervals/frequency for test medium samples: days 0, 7, 14, 21, 23, 28, 30
- 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 with UV detection @220 nm.

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 (Polyoxyethylen Sorbitan Monooleate)
- Concentration of vehicle in test medium (stock solution and final test solution(s) at different concentrations and in control(s)): 0.025 and 0.0025 mg/l
Dose 1: Test item: 0.025 mg/L , Vehicle: 0.075 mg/L
Dose 2: Test item: 0.0025 mg/L , Vehicle: 0.0075 mg/L
Vehicle Control: test item: - , Vehicle: 0.075 mg/L

Test organisms (species):

Cyprinus carpio

Details on test organisms:

Weight: 5.2 +/- 0.64 g
Length: 7.6 +/- 0.30 cm

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

30 d

Test temperature:

25 ° +/- 0.2 °C

pH:

7.75 +/- 0.25

Dissolved oxygen:

7.4 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, 23, 28, and 30. The analytical values show that the nominal concentrations of 0.025 and 0.0025 mg/L were maintained at about 100% using Tween 80, respectively. At days 0, 7, 14, 21, 23, 28, and 30 two fish each were removed from each test group. Body weight was determined. The fish were homogenised and extracted with acetonitrile and n-hexane. The extract was analysed with HPLC. Due to the low bioaccumulation potential, no depuration phase was required.

Nominal and measured concentrations:

nominal concentration 0.02 mg/L:
analytically measured concentrations:
day 0: 0.0235 mg/L;
day 7: 0.0238 mg/L;
day 14: 0.0229 mg/L
day 21: 0.0253 mg/L
day 23: 0.0239 mg/L
day 28: 0.0238 mg/L
day 30. 0.0261 mg/L

nominal concentration 0.003 mg/L
analytically measured concentrations:
day 0: 0.00222 mg/L
day 7: 0.00242 mg/L
day 14: 0.00235 mg/L
day 21: 0.00265 mg/L
day 23: 0.00227 mg/L
day 28: 0.00238 mg/L
day 30: 0.00238 mg/L

Details on estimation of bioconcentration:

according to guideline

Key result

Conc. / dose:

0.025 mg/L

Temp.:

25 °C

pH:

7.75

Type:

BCF

Value:

121 dimensionless

Basis:

normalised lipid fraction

Time of plateau:

23 d

Calculation basis:

steady state

Key result

Conc. / dose:

0.003 mg/L

Temp.:

25 °C

pH:

7.75

Type:

BCF

Value:

173 dimensionless

Basis:

not specified

Time of plateau:

21 d

Calculation basis:

steady state

Details on kinetic parameters:

Steady state was reached within 21-23 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 121 and 173 (mean: 145). 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 mean steady state BCF of 145 was observed. 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):

145 dimensionless