Transcript TCE Contamination of the Tucson Water Supply

TRICHLOROETHYLENE (TCE)
CONTAMINATION, EXPOSURE, AND CLEANUP
TUCSON, AZ
EPA Funded
Environmental Health Issues in Tucson
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Water Pollution
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Air Pollution
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TCE
1-4 Dioxane
Beryllium
Soil Pollution
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Gasoline spill
Sulfate Contamination
Environmental Health
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Environmental Health is the field of science that studies how
the environment influences human health and disease.
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Environmental health comprises those aspects of human health,
including quality of life, that are determined by physical, chemical,
biological, social, and psychosocial factors in the environment.
It also refers to the theory and practice of assessing, correcting,
controlling, and preventing those factors in the environment that
can potentially affect adversely the health of present and future
generations.
National Institute of Environmental Health Studies
World Health Organization
Southwest Environmental Health
Sciences Center funded by the NIEHS
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Investigates a variety of environmental health and
toxicology problems of local concern
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TCE contamination
Arsenic contamination
Air Pollution
Experts can provide cutting edge information based
on their research
Outreach can assist with risk communication and
discussions with the public
http://swehsc.pharmacy.arizona.edu
Courtesy of the Superfund Basic Research Program at the University of Arizona
http://coep.pharmacy.arizona.edu/tce/whatistce.html
Risk Assessment
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Toxicology is the study of poisons or the adverse
effects of chemical and physical agents on living
organisms.
Toxicologists study the extent and type of health
problems associated with a particular level of
chemical exposure and use what they learn to
assess the threat of that chemical to the health of
people in particular situations.
Routes of Entry
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The toxicant must enter the
body to cause a problem
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Inhalation – breathing
Ingestion – eating and
drinking
Absorption – through the
skin
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Questions to ask when an exposure
problem is suspected…
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Health Problem
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Hazard
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What is the source of the problem?
How much exposure are people in the area receiving?
People
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What are the symptoms?
What do the affected individuals have in common?
Are people exposed to a hazard?
What are the routes of exposure?
Is the exposure acute or chronic?
Connections
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Is a new health problem present?
Could the exposure be causing the problem?
Key Dose
Words
/ Response
Risk =
Hazard X Exposure
Individual Sensitivity
TCE General Properties
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Used as a solvent
Nonflammable, colorless liquid @RMT, sweet
odor and taste, lipophillic
Trade Names: Triclene, Vitran & others
EPA classifies TCE as a “likely”
cause of cancer
National Academy recommends it be labeled
as a cause of cancer and other health
problems - 2006
Source: Agency for Toxic Substances and Disease Registry. Public
Health Statement for Trichloroethylene, CAS# 79-01-6, Sept. 1997.
How does TCE
get into our
environment?
TCE Plume
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North of Los Reales
Rd
Hughes Access Road
to the East and South
Highway 89 to the
West
Plume traveling North
(bottom to top of
image)
Sources of Exposure
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Non-occupational Exposure :
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Ingestion (drinking water, food)
Inhalation (shower, household products)
Contact (shower, bath)
Increased exposure from…
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Living near waste / industrial sites
Drinking from private or certain public wells
Additive exposures (multiple routes & different
chemicals)
Source: Wu & Schaum, Exposure Assessment of TCE, Envr Hlth Prspctv, 108 (S2), 2000.
TCE
Exhaled
TCE
skin
intestines
Lungs
Systemic Circulation (Blood)
Kidney
(Glutathione)
Liver
(P450)
TCE
Metabolites
Generated
Urine
Source: Adapted from Lash, et al., Metabolism of Trichloroethylene, Envr Hlth Prspctv, 108 (S2), 2000.
TCE In Drinking Water
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Regulated by
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Title 42 U. S. Code
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Safe Drinking Water Act
(1974,1977, 1986, & 1996)
Maximum Contaminant Limits (MCL)
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MCL: 5 ppb
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ATSDR: < 1 cancer death over 30 years
MCLG (Goal): 0.0 ppb
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Can’t measure to 0.0 ppb to verify!
Source: 42 U.S.C. s/s 300f et.seq (1974);
History of TCE Use in Tucson
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Industrial activities released TCE into
soil and groundwater from 1950s to
1970s.
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U S Air Force Plant 44
162nd AANG facility
Burr-Brown (acquired by Texas
Instruments)
Many others that are out of business
Source: Tucson International Airport Area (TIAA) Superfund Information Library Site. 101 W. Irvington Road.
Community Exposure
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47,000 Southside residents were exposed
75% Hispanic, majority low income
Risk denied, responsibility dismissed, blurred
accountability
Increased incidence of cancers, birth defects, &
autoimmune diseases
Residents said it was the result of technology. Life
has no guarantees.
Sources: Assessment of Community Contamination: A Critical
Approach. Clark et al Pub Hlth Nurs, 19 (5): 354-365, Sept/Oct
2002. Baseline Human Health Risk Assessment: Tucson
International Superfund Site, ADHS, Dec 1996.
Evelina Street
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34 cancer cases documented
Currently several families have only 1 surviving
member
In 1991, Tucson’s City Attorney for environmental
affairs, T.J. Harrison,recommended the city council to
cease asking for federal funds related to Southside
treatment
Reasons for deaths: smoking, drinking, not using
seat belts, and obesity, not TCE exposure
Unified Community Action Board
(UCAB)
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Created by Raytheon Missile Systems Company
(RMSC) in 1995 by combining the Action Boards of
all the possible responsible parties
Largest Superfund Site in the country
Outreach program involves and empowers the local
community as major stakeholders in environmental
decisions
Stakeholders: General Public, community activists,
University of Arizona, Tucson International Airport,
the Air Force and RMSC
2006 The National Academy of Sciences
Risk Assessment - Health Effects TCE
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Kidney Toxicity and Cancer
Liver Toxicity and Cancer
Reproductive and
Developmental Toxicity
Neurotoxicity
Respiratory Toxicity and
Cancer
Immunotoxicity
http://coep.pharmacy.arizona.edu/tce/whatistce.html
References
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Public Health Statement for Trichloroethylene, Agency for Toxic Substances and
Disease Registry, CAS# 79-01-6, September 1997.
Wu, C. and Schaum, J., Exposure Assessment of Trichloroethylene, Envir Hlth Perspc,
v. 108, Suppl. 2, pp. 359-363, May 2000.
Lash, L., Fisher, J. W., Lipscomb, J. C., & Parker, J. C., Metabolism of Trichloroethylene,
Envir Hlth Perspc, v. 108, Suppl. 2, pp. 177-193, May 2000.
42 U.S.Code s/s 300f et.seq (1974)
Tucson International Airport Area (TIAA) Superfund Information Library Site. 101 W.
Irvington Road.
Clark, L., Barton, J.A. & Brown, N. J., Assessment of Community Contamination: A
Critical Approach, Public Health Nursing, v. 19, n. 5 pp. 354-365, September/October,
2002.
Baseline Human Health Risk Assessment: Tucson International Superfund Site, Arizona
Department of Health Services. December 1996.
Agency for Toxic Substances & Disease Registry. 1-4 Dioxane, CAS#123-91-1; 9/2004.
Agency for Toxic Substances & Disease Registry. Beryllium, CAS#7440-41-7; 9/2002.
THANK YOU
Based on a presentations to the Tucson
Unified Community Action Board by
Christine Krikliwy, 8 April 2005