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10
CH3041
BIOACCUMULATION
• Biomagnification
of a chemical occurs
when the fatty tissue from one organism is
consumed by another, a high BCF chemical present in the first is then concentrated in the tissue of the second. Progress up
the food chain results in substantial
increases in concentration.
when the fatty tissue from one organism is
consumed by another, a high BCF chemical present in the first is then concentrated in the tissue of the second. Progress up
the food chain results in substantial
increases in concentration.
eg DDT (ppm)
sea water 0.000003
Long Island Sound plankton 0.04
minnows 0.5
needlefish 2
cormorants 25
BCF 107
Long Island Sound plankton 0.04
minnows 0.5
needlefish 2
cormorants 25
BCF 107
• Degradation occurs
if metabolism can
break down the
chemical to a water
soluble, excretable form.
if metabolism can
break down the
chemical to a water
soluble, excretable form.
• eg. DDT
metabolises quickly (< 2d) to DDE
but DDE metabolises slowly (< 6months).
but DDE metabolises slowly (< 6months).
