Registration Dossier

Environmental fate & pathways

Bioaccumulation: aquatic / sediment

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

A test to determine the bioaccumulation of the test substance in sediment organism (Lumbriculus variegatus) was performed according to the OECD 315 testing guideline.  Rates of accumulation of [14C] 99422018 into L. variegatus were relatively slow with time to achieve 90% of the steady-state concentration being 23 and 55 days of initial exposure and low steady state bioaccumulation factors (BAFk) between 1.3 and 1.7 (fresh weight basis).  Elimination rates were equally slow with elimination half-life values of 7-16 days and elimination of 90% of the total radioactive residue within 23-55 days with the higher value probably reflecting variability at the 1 mg/kg concentration.
The calculated BAFss values were 1.17-1.37 (wet weight basis) and 2.78-4.13 (dry weight basis). These BAFs can be considered as very low.
Lipid content over the test period was determined as 2.56% based on weight. The biota-sediment accumulation factor (BSAF) expressed on the basis of lipid content were calculated as 0.34-0.45.
The higher BSAF obtained was converted into BCF according to the equilibrium partitioning theory (EqP) (Shea 1988, Di Torro et al. 1991 and Kraaij 2001). The BCF obtained was 4.15 L/kg.

Key value for chemical safety assessment

BCF (aquatic species):
4.15 L/kg ww

Additional information

No trigger values are available for BSAF in sediment for comparison with the PBT criteria. Shea (1988), Di Torro et al. (1991) and Kraaij (2001) have developed a model (the equilibrium partitioning theory) which assumes that if the pore water and the organis carbon are in equilibrium and if if the distribution over organic carbon and pore water can be described by the following constant :

K= Csed/Cpore water

then the BSAF = BCF/K

The BCF obtained were

Csed  (mg equivalent/kg) Cpore  (mg equivalent/L) Koc BSAF BCF (L/kg)
1 mg/kg dw 0.645 0.07 9.21 0.45 4.15
10 mg/kg dw 7.916 2.252 3.52 0.34 1.20

The highest BCF value is used as key value.

Di Toro, D.M., C.S. Zarba, D.J. Hansen et al. 1991. Technical basis for establishing sediment 21 quality criteria for nonionic organic chemicals using equilibrium partitioning. Environ Toxicol Chem 10:1541-1583.

Shea, D. 1988. Developing national sediment quality criteria. Environ Sci Technol 22: 1256-1261.

Kraaij, R. 2001. Sequestration and bioavailability of hydrophobic chemicals in sediment. Utrecht University. Thesis. 104 pp.