By Little Pro on 2016-02-01 Views: Update:2017-04-25
Bioconcentration Factor (BCF) is an indicator of a chemical substance’s tendency to accumulate in the living organism. It can be obtained by calculation method based on logPow or bio-accumulation test. Calculated BCF values are unitless and generally range from one to a million.
If an aquatic bioconcentration test (usually on fish) is conducted, BCF will be the concentration of test substance in/on the fish or specified tissues thereof (as mg/kg) divided by the concentration of the chemical substance in the surrounding medium (as mg/L or mg/Kg).
The unit of BCF is L/kg. The bioconcentration factor (BCF) may also be expressed as the ratio of the uptake rate constant (k1) to the depuration rate constant (k2).
n-octanol/water partition coefficient is often used as a screening test for bio-accumulation test. The assumption behind this is that the uptake of an organic substance is driven by its hydrophobicity. For organic substances with a Log Kow value below 4.5 it is assumed that the affinity for the lipids of an organism is insufficient to exceed the bio-accumulation criterion i.e. a BCF value of 2000.
Please be noted that Kow is not applicable for surface reactive substances, mixtures with molecular weight distributions, organic metal compounds, low-purity samples (expect HPLC method) and inorganic compounds.
You have learned the definition of bio-accumulation and bio-concentration factor (BCF), testing guidelines, and bio-concentration criteria in US and USA. .