Bioconcentration factor

Bioconcentration factor (BCF) is the concentration of a particular chemical in a biological tissue per concentration of that chemical in water surrounding that tissue. That is, a dimensionless number representing how much of a chemical is in a tissue relative to how much of that chemical exists in the environment.

$BCF={\frac {Concentration_{Organism}}{Concentration_{Environment}}}$

This physical property characterizes the accumulation of chemicals, including pollutants, through chemical partitioning from the aqueous phase into an organic phase. This may occur as in gills of a fish, or cell walls of aqueous plants.

In the context of setting exposure criteria it is generally understood that the terms "BCF" and "steady-state BCF"' are synonymous. A steady-state condition occurs when the organism is exposed for a sufficient length of time that the ratio does not change substantially.

Tissues with BCF greater than 1,000 are considered high, and under 250 low, with those between classified as moderate .

See also

• Bioconcentration Factor
• Bioaccumulation
• Biomagnification

BCF is correlated to the Partition coefficient via a logarithmic equation of the form $\log BCF=Y\times \log KOW-Z$ where Y ranges from 0 and 1 depending on the compound.