Presentation on theme: "Health Assessment Team"— Presentation transcript:
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 Liaisonthe team will:Identify human populations at riskReduce and prevent adverse human health conditions from toxic environmental exposuresEducate 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 Background1993 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 environment98% of US Manufacture by Monsantotradename – AroclorAroclor 1254 (12 C atoms, 54% Cl) generally the more chlorinated, the more toxicOther 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 rashesLong term exposure may cause liver damageA 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 learningYoung children may also experience developmental health effects from eating contaminated fishLipophilic – loves fatty tissue
11 Nature and Extent of Contamination DSHS fish ban in place since February 1994area covered by the ban includes the irrigation canal beginning at the Rio Grande and up to and including the reservoirfish contain PCB (polychlorinated biphenyl)possession of fish from the canal and reservoir can result in a fine up to $500
19 Findings PCB (Aroclor 1254) found in fish tissue & suspended sediments Fish (range: BDL – ppm mean: ppm)FDA limit: 2 ppmEPA limit: 1.4 ppm – state should consider actionSuspended 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 PCBsair – 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 sourceDSHS Community InvolvementDSHS Health Education
22 Health Education Example of pamphlet Door hanger Attend local school functionsVisit businesses(sporting goods, jiffy marts, etc.)