1. Donna Reservoir and Canal System “Superfund” Site Donna, Hidalgo County, Texas

2. Health Assessment Team
The assessment team conducts Public Health Assessments on hazardous waste sites following proposal to the Environmental Protection Agency’s National Priorities List (Superfund)

3. the team will: Identify human populations at risk
Health Assessor, Health Educator, Community Liaison
the team will:
Identify human populations at risk
Reduce and prevent adverse human health conditions from toxic environmental exposures
Educate communities on exposure prevention and pathways

4. Health Assessment The Health Assessment has 3 versions:
Technical – Reviewed by state & federal environmental agencies for their approval.
Public Comment – Reviewed by the public. Comments from the public regarding the health assessment are received by DSHS.
Final – document is finalized. Comments received are answered and incorporated into the document. Public comments can alter the final outcome.

5. Health Assessment Team 
Map Key:  
   Proposed: 3
   Final: 46
   Deleted: 10

7. Background
1993 EPA was investigating neural tube defect cluster in the Valley area.
A family gave EPA a tissue (fillet) sample from a fish supposedly caught in the Donna Canal.
The fish had a concentration of 399 ppm PCB. The highest ever recorded in a fish.
Investigations of reservoir & canal began as result.

8. Polychlorinated Biphenyl structure (209 possible combinations)

9. PCBs Withstand high heat – transformers and capacitors
Very stable - therefore persistent for long periods of time in the environment
98% of US Manufacture by Monsanto
tradename – Aroclor
Aroclor 1254 (12 C atoms, 54% Cl) generally the more chlorinated, the more toxic
Other countries also produced PCBs.
1978 ban - US production & importation

10. Potential Health Effects
The most commonly observed long term health effects in people exposed to high levels of PCB’s are skin conditions such as acne and rashes
Long term exposure may cause liver damage
A pregnant woman who eats food contaminated with high levels of PCB’s can pass the chemicals to her unborn child and may cause the child to have slower mental development and difficulty learning
Young children may also experience developmental health effects from eating contaminated fish
Lipophilic – loves fatty tissue

11. Nature and Extent of Contamination
DSHS fish ban in place since February 1994
area covered by the ban includes the irrigation canal beginning at the Rio Grande and up to and including the reservoir
fish contain PCB (polychlorinated biphenyl)
possession of fish from the canal and reservoir can result in a fine up to $500

12. DSHS Fish Ban

19. Findings PCB (Aroclor 1254) found in fish tissue & suspended sediments
Fish (range: BDL – ppm mean: ppm)
FDA limit: 2 ppm
EPA limit: 1.4 ppm – state should consider action
Suspended sediments (range: nd – ppm)

20. Exposure Pathways Public health hazard – ingestion of fish
No public health hazard - exposure pathway eliminated:
surface water, drinking water, and bottom sediment – no PCBs
air – no samples collected (low volatility high affinity for soil)
No apparent public health hazard:
suspended sediment - not significant exposure pathway
(low probability of regular exposure)
Public health hazard – ingestion of fish

21. Actions Planned EPA will continue removing fish
EPA seeking contaminant source
DSHS Community Involvement
DSHS Health Education

22. Health Education Example of pamphlet Door hanger
Attend local school functions
Visit businesses
(sporting goods, jiffy marts, etc.)

23. Community Involvement – public meetings

24. Health Assessment Team Contacts
Health Assessment and Toxicology Group
Environmental & Injury Epidemiology & Toxicology Branch
(800)
Tom Ellerbee
Environmental Specialist
Tina Walker
Health Educator
Nancy Ingram
Community Liaison