PCB Biomagnification: Its bad news.

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PCB BiomagnificationIts bad news.

• Ezra Selove
• Bi 370 12-18-02

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What are they?

• Polychlorinated Biphenyls (PCBs)
• Synthetic organic chemicals
• Oily liquids to solids
• Non-flammable (high melting points)
• Electrical insulating properties

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They were quite ubiquitous.

• Hundreds of industrial and commercial
  applications including
• electrical
• heat transfer
• and hydraulic equipment
• as plasticizers in paints
• plastics and rubber products
• More than 1.5 billion lbs. made prior to 1977

YMCA!
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Wait, theyre bad for you?

• They are a carcinogen
• They also effect your
• immune system
• reproductive system
• nervous system
• endocrine system

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Get rid of em!

• In 1976, Congress passed the Toxic Substances
  Control Act (TSCA)
• Prohibited their creation
• Cradle to the grave tracking

Congress
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They are still here.

• Because so much was produced, some is still
  lingering
• And now for the model!

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Schematic of Ecosystem
F01 M R Sin(2 Pi (T - 11) / 52)
F10N1 r10
F20N2 r20
F30N3 r30
PrimaryProducersN1
Herbivores N2
PredatorsN3
F12 N1 N2 t12
F23 N2 N3 t23
F24N2 d24
F34N3 d34
F14N1 d14
DecomposersN4
F40N4 r40
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Schematic of Ecosystem w/PCBs
dz1 F01 - (F12 C1) - (F14 C1) (F40 C4)
dt
dz2 (F12 C1) - (F23 C2) - (F24 C2) dt
dz3 (F23 C2) - (F34 C3) dt
dz4 (F14 C1) (F24 C2) (F34 C3) - (F40
C4) dt
PrimaryProducersN1
Herbivores N2
PredatorsN3
dz2
dz1
dz1
dz2
F01
dz3
DecomposersN4
dz4
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No Loss.

• There is no loss, so the PCBs continue to
  accumulate.
• Therefore, they are bad.