Why can't we eat our fish? What's in the water?

850 views

Published on

0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
850
On SlideShare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
13
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Why can't we eat our fish? What's in the water?

  1. 1. Why can’t we eat our fish?  What's in the water? Patricia K. Eagon, PhD University of Pittsburgh Department of Medicine Division of Gastroenterology, Hepatology, and Nutrition [email_address]
  2. 2. Q: How dirty is our local water? A: It’s really bad!!
  3. 3. Surface waters with impaired or threatened uses, by county (data from State & EPA) <ul><li>Allegheny 80-90% </li></ul><ul><li>Armstrong 70-80% </li></ul><ul><li>Butler 70-80% </li></ul><ul><li>Jefferson 60-70% </li></ul><ul><li>Westmoreland 70-80% </li></ul><ul><li>Warren 0-10% </li></ul><ul><li>0% = cleanest; 100% = dirtiest </li></ul>
  4. 4. Worst watersheds in USA <ul><li>Lower Allegheny 80-90% </li></ul><ul><li>Lower Monongehela 70-80% </li></ul><ul><li>Kiskiminetas 80-90% </li></ul><ul><li>Upper Ohio 80-90% </li></ul><ul><li>Mid Allegheny 30-40% </li></ul><ul><li>(Tionesta) </li></ul><ul><li>0% = cleanest; 100% = dirtiest </li></ul>
  5. 5. Counties with the most facilities exceeding Clean Water Act permits (recent 18 month period) <ul><li>New Haven County, CT </li></ul><ul><li>Hartford County, CT </li></ul><ul><li>Fairfield County, CT </li></ul><ul><li>Harris County, TX (Houston) </li></ul><ul><li>Worcester County, MA (Boston area) </li></ul><ul><li>Allegheny County, PA </li></ul><ul><li>Calcasieu Parish, SW Louisiana </li></ul><ul><li>Erie County, NY, (Buffalo) </li></ul>
  6. 6. Q: How contaminated are our fish? A: Depends where you catch them!!
  7. 7. Mercury content of channel catfish (ppm) <ul><li>Allegheny River, Ford City 24 </li></ul><ul><li>Beaver River, New Brighton Dam 0.07 </li></ul><ul><li>Delaware River (2 locations) 17, 18 </li></ul><ul><li>Schuylkill River (various) 0.05 </li></ul><ul><ul><ul><ul><ul><li>29-59 </li></ul></ul></ul></ul></ul><ul><li>Susquehanna River 11-78 </li></ul><ul><li>EPA guidelines: fish with 0.5-1.0 ppm, no more than ONE meal/month should be consumed. </li></ul><ul><li>Above 2 ppm, do not eat </li></ul>
  8. 8. Mercury in the environment: where does it come from? <ul><li>Power plants 52 </li></ul><ul><li>Municipal waste combustion 30 </li></ul><ul><li>Medical waste combustion 16 </li></ul><ul><li>Hazardous waste combustion 7 </li></ul><ul><li>(tons per year) </li></ul>
  9. 9. Dangers of Mercury <ul><li>Mercury never goes away!! </li></ul><ul><li>Major human source is by consuming fish (methylmercury) </li></ul><ul><li>The older the fish, the more mercury! </li></ul><ul><li>Passes through placenta to fetus, and breast milk to baby </li></ul><ul><li>Impairs development/function of central nervous system </li></ul><ul><li>Effects similar to lead exposure </li></ul>
  10. 10. Who is at greatest risk? <ul><li>Children </li></ul><ul><li>Fetuses </li></ul><ul><li>Native Americans </li></ul><ul><li>Asian Americans </li></ul><ul><li>The poor who fish for food, primarily older Blacks </li></ul>
  11. 11. So, what else is going on with our fish?? Fish are sensitive monitors of the environment, and what’s bad for the fish is bad for us!
  12. 12. Fish & wildlife as sensors of endocrine disrupting chemicals <ul><li>Reproductive problems: </li></ul><ul><li>Intersex fish near outflow of sewage plants </li></ul><ul><li>Great Lakes fish exposed to PCBs </li></ul><ul><li>Fish-eating birds and mammals </li></ul><ul><li>Florida alligators after pesticide spills </li></ul><ul><li>Baltic Sea seals </li></ul><ul><li>Florida panthers </li></ul>
  13. 13. What are endocrine disruptors? <ul><li>Chemicals that can: </li></ul><ul><li>mimic natural hormones </li></ul><ul><li>block action of natural hormones </li></ul><ul><li>interact with receptors for natural chemicals & hormones </li></ul><ul><li>change the metabolism of natural hormones </li></ul><ul><li>increase sensitivity to hormones & mimics </li></ul><ul><li>Not just reproductive hormones (estrogen & testosterone), also thyroid & ? insulin </li></ul>
  14. 14. What chemicals are endocrine disruptors? <ul><li>DDT </li></ul><ul><li>Dioxin </li></ul><ul><li>PCBs (transformers) </li></ul><ul><li>Kepone </li></ul><ul><li>Bisphenols, phthalates (plastics manufacturing) </li></ul><ul><li>Pesticides: dieldrin, chlordane </li></ul><ul><li>Alkylphenols: plastics, industrial detergents, spermicide </li></ul><ul><li>Polyalkylated hydrocarbons (PAH): industrial chemicals, many uses </li></ul>
  15. 15. Outcomes of endocrine disruption <ul><li>Fish: expression of both sex organs (intersex) </li></ul><ul><li>Many species: reduction in fertility, conception, full-term offspring, changes in sex ratios </li></ul><ul><li>Precocious puberty in humans </li></ul>
  16. 16. Probable effects on humans <ul><li>Human sperm density declines in concert with increased environmental pollution levels. </li></ul>
  17. 17. Probable effects on humans <ul><li>Sarnia region of Ontario’s “Chemical Valley” </li></ul><ul><li>contaminated: polychlorinated biphenyls, polyaromatic hydrocarbons, hexachlorobenzene, mirex, toxic metals, volatile organics, phthalates, dioxins; all known or suspected endocrine disruptors </li></ul><ul><li>Male Births: All Canada: 51.2% </li></ul><ul><li>Sarnia: 1993-03 41.2% </li></ul><ul><li> 1999-03 34.8% </li></ul>
  18. 18. The plasticizer DEHP alters liver estrogen metabolism 4 8 16 WEEKS ON DIET 0 1 2 3 4 5 Activity (nmol/min-mg protein) E2-OHase CONTROL DEHP * p<0.05 * * E Sulfotransferase 4 8 WEEKS ON DIET 0 1 2 3 4 Activity (pmol/mg protein) CONTROL DEHP * p<0.05 *
  19. 19. DEHP increases blood estrogen levels 4 8 16 WEEKS ON DIET 0 25 50 75 100 125 150 175 200 Percent of Control CONTROL DEHP * * * * p<0.05
  20. 20. Endocrine disruptors are linked to human cancers <ul><li>Great Lakes fish eaters: </li></ul><ul><li>Increased # of breast cancers (BrCa) </li></ul><ul><li>Developmental/neurological abnormalities </li></ul><ul><li>Taiwan: PCB, developmental abnormalities in boys born up to 6y after exposure </li></ul><ul><li>Long Island: BrCa increase with proximity to PCB contamination </li></ul><ul><li>Iowa, NC: BrCa in farm wives exposed to chlorinated pesticides </li></ul><ul><li>CA: Hispanic farmworkers, increased BrCa when exposed to chlordane, malathion, 2,4D; especially in younger women </li></ul>
  21. 21. Q: What can we do about the fish and about ourselves?
  22. 22. What can we do? <ul><li>Demand clean water </li></ul><ul><li>Demand that our industries comply with the Clean Water Act and reduce emissions </li></ul><ul><li>Be aware of exposures to pesticides, toxins, endocrine disruptors in the home & workplace </li></ul><ul><li>Know your fish: reduce/eliminate intake of contaminated species, including local sport fish </li></ul><ul><li>Consider organic foods, especially oils, grains, and hard-to-wash vegetables </li></ul><ul><li>Support organizations that demand clean water, clean air, and a clean food supply!! </li></ul>
  23. 23. What current research is being done locally? <ul><li>UPCI Center for Environmental Oncology: education, greening of new buildings, research in many factors that may influence immunity and cancer (Dr. Devra Davis et al.) </li></ul><ul><li>The Three Rivers Fish Study: </li></ul><ul><li>Work with community groups to sample local fish and determine levels of heavy metals, chemicals, and endocrine disruptors (Dr. Dan Volz) </li></ul>

×