Sonoma State University - Hanes
Department of Biology Environmental Toxicology

PCB's in the Hudson River; Guthrie & Perry

Outline:

• I. Introduction - PCB's have badly contaminated the Hudson River. They have also been above EPA limits in fish of the Great Lakes and Finger Lakes.
• II. Characteristics of PCB's - See generalized chemical structure.
  • A. Thermally stable, non-reactive with acid, bases and many chemicals, low vapor pressure, low water solubility, mixes with many polymers and organic solvents, excellent electrical insulator.
  • B. Few chorines on molecule make it liquid, more - resinous, still more - crystalline.
  • C. Uses
    • 1. Insulator in large and small capacitors and transformers.
    • 2. Plasticizer to cause polymerization
    • 3. Hydraulic fluid
    • 4. Adhesives
    • 5. Carbonless carbon paper
  • D. Acute toxicities
    • 1. Chloracne from skin contact or taken internally
    • 2. Liver damage - jaundice, nausea, weight loss, edema, abdominal pain from internal poisoning.
    • 3. Rice oil Disease in Japan - 2000 ppm caused eye discharge, acne, uterine ulcer, excess pigmentation, miscarriage, stillbirth, abnormal pigmentation on infants
    • 4. LD50's of 250 to 1300 mg/Kg - more toxic as less chlorination
  • E. Chronic toxicities - a serious problem because of persistance. Tolerance limit in food is 5 ppm
    • 1. In mammals first signs are liver damage
    • 2. In birds - damaged pericardia, kidneys, spleen & liver
    • 3. Shell thinning in birds
      • a. Lowers estrogen by stimulating steroid hydroxylases
      • b. Reduces carbonic anhydrases which influence calcium transfer from blood to oviduct
    • 4. A great deal of bioaccumulation in birds and fish.
• III. Sources of Pollution
  • A. Monsanto produced 400,000 tons between 1948-73 about 1/2 of the world supply. Restricted use to "closed cycle" in 1971
  • B. G.E. on the Hudson River bought 15% of U.S. Production for transformers and capacitors.
    • 1. In '71, NY bureau of fisheries reported 11 ppm in stripped bass eggs and 4 ppm in their flesh.
    • 2. With EPA established a requirement to obtain discharge permits, GE applied for and got a permit to discharge 30 lbs/day.
    • 3. Discharges were retained in sediment behind a dam that was removed in 73 and in 76 there was a flood that moved large loads of sediment
    • 4. In 76 because of a suit by NY dept. of Environmental Conservation, NY state regulation and G.E. were found at fault and discharge was limited to 1 lb/day on Sept 76, 1 g/day by May 77 and none by July
    • 5. Spread of PCB also came from municipal sewerage, leaching from landfills & from atmosphere from burning.
• IV. Persistence
  • A. Forms a film on particles and settles in sediments
    • 1. It can be slowly metabolized, but requires oxygen
    • 2. Reduces growth of plants and bacteria
• V. Disposal on land
  • A. Dredge spoils from river maintenance contain large amounts of PCB's spread by dust, uptake by plants from dust on leaves. Leaches back into river or from where it is trucked off to land fills.
• VI. Distribution of PCB's in the Hudson River Basin
  • __________Site_________PCB's (tons)_______________________________
  • Upper Hudson 440
  • Lower Hudson 220
  • Landfills and dumps 530
  • Dredge spoils 160
  • River biota 0.1-1
• VII. Possible remedies
  • A. A number of possible remedies have been thought of, a few tried on a pilot scale or tested in the laboratory. U.V. light will destroy it, but that means exposure to sunlight. The most economical would be destruction by micro-organisms. Besides some dredging however, little has been done but wait out the settling of the PCB's and perhaps this is the only thing that would be economical. The oyster and clam fishery of the Hudson bay has now been allowed to return and it seems that without major floods or sediment disturbance the river is becoming clean enough for use again.

Exercises:

1. Name the physical and chemical characteristics and relate how these make PCB's useful.

2. What changes with PCB's of increasing chlorination?

3. What are some acute symptoms of PCB exposure? Chronic exposure?

4. Why is PCB so widespread in the environment?

5. How did the Hudson River get so much PCB?

6. Why does shell thinning take place in birds?

7. What are the problems associated with the PCB's in the Hudson River?

Why is it so hard to get rid of?