TRICHLOROETHYLENE (TCE) CONTAMINATION, EXPOSURE, AND CLEANUP

TUCSON, AZ

EPA Funded

Environmental Health Issues in Tucson

Water Pollution– TCE– 1-4 Dioxane

Air Pollution– Beryllium

Soil Pollution– Gasoline spill– Sulfate Contamination

Environmental Health

Environmental Health is the field of science that studies how the environment influences human health and disease.

– 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 StudiesWorld Health Organization

Southwest Environmental Health Sciences Center funded by the NIEHS

Investigates a variety of environmental health and toxicology problems of local concern

– 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

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

The toxicant must enter the body to cause a problem

Inhalation – breathing Ingestion – eating and

drinking Absorption – through the

skin

Questions to ask when an exposure problem is suspected…

Health Problem– What are the symptoms? – What do the affected individuals have in common?

Hazard– What is the source of the problem? – How much exposure are people in the area receiving?

People– Are people exposed to a hazard?– What are the routes of exposure? – Is the exposure acute or chronic?

Connections– Is a new health problem present?– Could the exposure be causing the problem?

Key Words

Risk =

Hazard X Exposure

Dose / Response

Individual Sensitivity

TCE General Properties

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

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

Non-occupational Exposure :– Ingestion (drinking water, food)– Inhalation (shower, household products)– Contact (shower, bath)

Increased exposure from…– 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.

Source: Adapted from Lash, et al., Metabolism of Trichloroethylene, Envr Hlth Prspctv, 108 (S2), 2000.

intestines

TCE

Liver

(P450)

TCE

Metabolites

Generated

Kidney

(Glutathione)

Urine

Lungsskin

Systemic Circulation (Blood)

Exhaled

TCE

TCE In Drinking Water

Regulated by– Title 42 U. S. Code– Safe Drinking Water Act (1974,1977, 1986, & 1996)

Maximum Contaminant Limits (MCL)– MCL: 5 ppb

ATSDR: < 1 cancer death over 30 years

– MCLG (Goal): 0.0 ppb 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

Industrial activities released TCE into soil and groundwater from 1950s to 1970s. – 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

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

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)

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

Risk Assessment - Health Effects TCE

Kidney Toxicity and Cancer Liver Toxicity and Cancer Reproductive and

Developmental Toxicity Neurotoxicity Respiratory Toxicity and

Cancer Immunotoxicity

2006 The National Academy of Sciences

http://coep.pharmacy.arizona.edu/tce/whatistce.html

References

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