Evaluation of PCE and TCE in Residential Indoor Air
PALERMO WELL FIELD GROUND WATER CONTAMINATION
TUMWATER, THURSTON COUNTY, WASHINGTON
EPA FACILITY ID: WA0000026534
January 29, 2002
Washington State Department of Health
Under a Cooperative Agreement with the
Agency for Toxic Substances and Disease Registry
TABLE OF CONTENTS
- Occurring over a short period of time. An acute exposure is one which lasts for less than 2 weeks.
- Agency for Toxic Substances and Disease Registry (ATSDR):
- The principal federal public health agency involved with hazardous waste issues, responsible for preventing or reducing the harmful effects of exposure to hazardous substances on human health and quality of life. ATSDR is part of the U.S. Department of Health and Human Services.
- Cancer Slope Factor:
- A number assigned to a cancer causing chemical that is used to estimate it's ability to cause cancer in humans.
- Any substance that can cause or contribute to the production of cancer.
- A long period of time. A chronic exposure is one which lasts for a year or longer.
- Comparison value:
- A concentration of a chemical in soil, air or water that, if exceeded, requires further evaluation as a contaminant of potential health concern. The terms comparison value and screening level are often used synonymously.
- Any chemical that exists in the environment or living organisms that is not normally found there.
- A dose is the amount of a substance that gets into the body through ingestion, skin absorption or inhalation. It is calculated per kilogram of body weight per day.
- Environmental Media Evaluation Guide (EMEG):
- A concentration in air, soil, or water below which adverse non-cancer health effects are not expected to occur. The EMEG is a comparison value used to select contaminants of potential health concern and is based on ATSDR's minimal risk level (MRL).
- Contact with a chemical by swallowing, by breathing, or by direct contact (such as through the skin or eyes). Exposure may be short-term (acute) or long-term (chronic).
- Water found underground that fills pores between materials such as sand, soil, or gravel. In aquifers, groundwater often occurs in quantities where it can be used for drinking water, irrigation, and other purposes.
- Hazardous substance:
- Any material that poses a threat to public health and/or the environment. Typical hazardous substances are materials that are toxic, corrosive, ignitable, explosive, or chemically reactive.
- Lowest Observed Adverse Effect Level (LOAEL):
- LOAELs have been classified into "less serious" or "serious" effects. In dose-response experiments, the lowest exposure level at which there are statistically or biologically significant increases in the frequency or severity of adverse effects between the exposed population and its appropriate control.
- Soil, water, air, plants, animals, or any other part of the environment that can contain contaminants.
- Minimal Risk Level (MRL):
- An amount of chemical that gets into the body (i.e., dose) below which health effects are not expected. MRLs are derived by ATSDR for acute, intermediate, and chronic duration exposures by the inhalation and oral routes.
- No apparent public health hazard:
- Sites where human exposure to contaminated media is occurring or has occurred in the past, but the exposure is below a level of health hazard.
- No Observed Adverse Effect Level (NOAEL):
- The dose of a chemical at which there were no statistically or biologically significant increases in frequency or severity of adverse effects seen between the exposed population and its appropriate control. Effects may be observed at this dose but were judged not to be "adverse."
- Compounds composed of carbon, including materials such as solvents, oils, and pesticides which are not easily dissolved in water.
- Parts per billion (ppb)/Parts per million (ppm):
- Units commonly used to express low concentrations of contaminants. For example, 1 ounce of trichloroethylene (TCE) in 1 million ounces of water is 1 ppm. 1 ounce of TCE in 1 billion ounces of water is 1 ppb. If one drop of TCE is mixed in a competition size swimming pool, the water will contain about 1 ppb of TCE.
- An area of contaminants in a specific media such as groundwater.
- Remedial investigation:
- A study designed to collect the data necessary to determine the nature and extent of contamination at a site.
- U.S. Environmental Protection Agency (EPA):
- Established in 1970 to bring together parts of various government agencies involved with the control of pollution.
- Volatile organic compound (VOC):
- An organic (carbon-containing) compound that evaporates (volatilizes) easily at room temperature. A significant number of the VOCs are commonly used as solvents.