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TABLES (Cont.)

Table 5.

Chemicals of Interest in Creek Sediments and Site M Before Remediation in parts per million (ppm)
Chemical of Interest Maximum Level Detected at each Location Comparison Value
CS-B CS-C CS-D CS-E CS-F Site M OPDC Reference Areas CV for Child Source
Dioxins and Furans as 2,3,7,8-TCDD (1) 0.012 0.0029 0.0007 0.0005 0.0003 0.0039 0 0.00001 0.00005 CEMEG
Total PCBs 226.1 48.25 10.6 8.76 6.2 12.2 ND ND 0.4 CREG
Arsenic 38 28 17 16 19 35 7.2 8 0.5 CREG
Cadmium 25 20 15 14 47 17 ND 0.65 10 CEMEG
Lead 1,000 480 260 310 320 530 16 26 NV NV
Thallium 2.1 ND ND 1.9 ND ND ND ND NV NV
Zinc 26,000 41,000 19,000 2,300 11,000 2,400 60 96 20,000 CEMEG
Benzo(a)pyrene 1.2 1.4 0.56 0.42 ND 1.5 ND ND 0.1 CREG
Benzo(a)anthracene 0.87 0.89 0.42 0.34 ND 1.3 ND ND NV NV
Benzo(b)fluoranthene 2 2 0.97 0.52 ND 1.5 ND ND NV NV
Benzo(k)fluoranthene 1.2 1.2 0.66 0.6 ND 1.8 ND ND NV NV
Chrysene 1.8 1.5 0.79 0.66 0.074 1.5 ND ND NV NV
Indeno(1,2,3-cd)pyrene 1.1 ND ND 0.43 ND ND ND ND NV NV
Dieldrin ND ND ND 0.09 0.093 ND ND ND 3 CEMEG
Heptachlor 0.5 0.0097 ND 0.0005 0.0009 0.059 ND ND 0.2 CREG

1 The total toxicity equivalent as 2,3,7,8-Tetrachlorodibenzo-p-dioxin
OPDC - Old Prairie DuPont Creek
CREG - Cancer Risk Evaluation Guide
CEMEG - Chronic Environmental Media Evaluation Guide
NV - No Comparison Value
ND - Not Detected

Table 6.

Chemicals of Interest in Creek Sediments and Site M After Remediation in parts per million (ppm)
Chemical of Interest Maximum Level at Each Location Comparison Value (CV)
CS-B CS-C CS-D CS-E CS-F Site M CV for Child Source
Dioxins and Furans as 2,3,7,8-TCDD (1) 0.00795 5.1E-05 0.001323 0.000186 0.000667 0.007241 5E-05 CEMEG
Total PCBs 86.7 0.178 2.44 1.25 0.3569 10 0.4 CREG
4-Nitrophenol 0.44 ND ND ND ND ND NV NV
Carbazole 0.62 ND ND ND ND 0.032 NV NV
Benzo(a)anthracene 1.9 ND 0.26 0.26 0.092 0.72 NV NV
Benzo(a)pyrene 1.2 ND 0.14 0.42 0.19 0.49 0.1 CREG
Benzo(b)fluoranthene 1.4 0.27 0.26 0.51 0.18 0.64 NV NV
Benzo(k)fluoranthene 0.9 0.27 0.26 0.37 0.13 0.34 NV NV
Chrysene 1.9 ND 0.26 0.37 0.14 0.82 NV NV
Dibenzo(a,h)anthracene 0.34 ND ND 0.14 ND 0.15 NV NV
Indeno(1,2,3-cd)pyrene 0.83 ND 0.18 0.35 0.11 0.17 NV NV
Arsenic 44 14 18 20 19 30 0.5 CREG
Cadmium 57 24 40 38 70 21 10 CEMEG
Lead 700 140 150 400 450 270 NV NV
Nickel 630 570 530 600 630 1,700 1,000 RMEG
Thallium 2.1 1.2 1.1 1.8 3.2 0 3 RMEG
Dieldrin 0.05 0.011 0.69 0.034 0.0082 0 0.04 CREG
Heptachlor epoxide 0.41 0 0 0.095 0 0.86 0.02 CREG

1 The total toxicity equivalent as 2,3,7,8-Tetrachlorodibenzo-p-dioxin
CREG - Cancer Risk Evaluation Guide
RMEG - Reference Dose Media Evaluation Guide
CEMEG - Chronic Environmental Media Evaluation Guide
ND - Compound not detected
NV - No comparison value

Table 7.

Chemicals of Interest in Air Samples Upwind and Downwind of Sauget Area 1 in micrograms per cubic meter (µg/m3) and parts per billion (ppb)
Chemical of Interest Upwind Downwind Comparison Value
g/m3 ppb g/m3 ppb ppb g/m3
1,1-Dichloroethene 32.57 8.21 27.47 6.93 20 0.02
Methylene chloride 300 86.37 2424 679.8 300 3
2-Methylnaphthalene 0.15 0.0258 0.15 0.0258 NL NL
2-Nitroaniline ND ND 0.03 0.0053 NL NL
4-Methyl-2-pentanone (MIBK) ND ND 106 21.6 NL NL
Acenaphthylene 0.03 0.005 0.04 0.0064 NL NL
Benzyl alcohol 0.03 0.007 ND ND NL NL
bis(2-Ethylhexyl)phthalate 0.07 0.004 0.08 0.005 NL NL
Dibenzofuran 0.04 0.006 0.04 0.0058 NL NL
Diethylphthalate 0.05 0.006 0.03 0.0033 NV NV
Dimethylphthalate 0.05 0.006 0.07 0.0088 NV NV
Fluorene 0.03 0.004 0.03 0.0044 NV NV
Isopropylbenzene 1.67 0.3397 22.12 4.5 NL NL
n-Butylbenzene ND ND 1.45 0.264 NL NL
Phenanthrene 0.04 0.006 0.06 0.0082 NV NV
Phenol 0.06 0.0156 ND ND NV NV
p-Isopropyltoluene ND ND 8.8 1.6 NL NL
s-Butylbenzene ND ND 2.2 0.4 NL NL
t-Butylbenzene ND ND 9.4 1.71 NL NL
1998 Total TEQ w/ EMPC1 as 0.000030 NC 0.00004 NC NV NV

EMEG - Environmental Media Guide
CREG - Cancer Risk Environmental Guide
NL - chemical not listed on ATSDR Comparison Value Tables
NV - No Value
NC - Concentration for TEQ 2,3,7,8-TCDD equivalents could not be calculated
ND - Not Detected
TEQ - Toxicity Equivalent (of 2,3,7,8-TCDD)
EMPC - estimated maximum possible concentration

Table 8.

Chemicals of Interest in Fish Fillets based on 26 Week per Year Child Exposure (in mg/kg-day)
Chemical of Interest Estimated Dose Health Guideline Source
Dioxins and Furans as 2,3,7,8-TCDD (1) 2 x 10-08 1 x 10-09 C MRL
Arsenic 0.0045 0.003 C MRL

1 The total toxicity equivalent as 2,3,7,8-Tetrachlorodibenzo-p-dioxin
C MRL - Chronic Minimal Risk Level

Child exposure dose assumes 16 grams consumed per day, 26 weeks per year, based on a 16 kilogram child.

Table 9.

Completed exposure pathways.
Pathway Name Source Medium Exposure Point Exposure Route Receptor Population Time of Exposure Exposure Activities Estimated Number Exposed Chemicals
Ambient Air Various Sites of Area 1 Air Air near sites G, H, I and L of Area 1 Inhalation Workers and residents Past
Breathing 70 Table 2
Creek Sediments Dead Creek Sediments Dead Creek Sediments Dermal
Residents Past
100 Tables 5 & 6
Surface Water Dead Creek Surface Water Dead Creek Dermal
Residents Past
100 Table 4
Fish Borrow Pit Lake Fish Fish Meals Ingestion Residents Past
Eating fish from Borrow Pit Lake 10 Table 8
Residential Surface Soil Residential Surface Soil Soil Homes Ingestion
Residents Past
Contacting soil 100 Table 2
On-site surface soil On-site soil Surfacing waste Soil Sites H and L Ingestion
Trespassers Past
Contacting contaminated soil 10 Table 1

Table 10.

Potential exposure pathways
Pathway Name Source Medium Exposure Point Exposure Route Receptor Population Time of Exposure Exposure Activities Estimated Potential Number Exposed Chemicals
On-site Contamination Area 1 On-site soil

Subsurface soil



Sites G, H, I and L Ingestion
Remedial Workers

Area Residents

Future Subsurface soil and waste excavation or removal

Groundwater monitoring or remediation

Breathing chemicals released during excavation

25 Tables 1 and 2
Residential Groundwater Area 1 Groundwater none currently

Perhaps soil-gas in future

Inhalation Residents Future Breathing in possible affected homes 25 Volatile Organic Compounds in Table 3


Table 11.

Population Estimates for Sauget Area 1 Sites.
Media/Location Radius
(in miles)
< 5 years
5-17 years
Total Population


43 110 567
All Creek Sectors



































Fish/Borrow Pit Lake





* Population in area where surface soil was tested, this area was bordered by Queeny Ave to the north, Illinois Route 3 to the west, Falling Springs Road to the east, and Camp Jackson Road to the south.

Source of population data: 2000 US Census Data.




Based on the information reviewed, IDPH concludes:

  1. The Area 1 Sauget Sites in Sauget and Cahokia, Illinois pose a public health threat basedon chronic exposure to contaminated sediments in Creek Segments B through F. Children havebeen observed playing in and around Dead Creek and are the population most likely to be exposedto the contaminated sediments. Since Dead Creek is an intermittent stream, the sediments are exposed much of the time especially during the summer months.

  2. Airborne exposures to Site G contaminants including PCBs, are occurring by volatilizationand fugitive dust generation. The population that would be exposed to airborne Site Gcontaminants are nearby residents and employees in are industries and businesses.

  3. Private wells near Creek Segment B contain low levels of contaminants. An increasedcancer risk is possible from the arsenic in the groundwater. However, exposure from drinkingcontaminated well water could be eliminated if all the homes were connected to a municipal watersupply and the private wells are properly sealed.

  4. Exposure to site-related contaminants would likely have been higher in the past. Duringpast site operations, especially at sites G, H, I and Creek Segment A, site-related contaminantexposures to area residents and employees would likely have been much higher than they aretoday. The employees on the site during active site operations potentially could have been exposedto very high levels of site-related contaminants since they were working in close proximity to themore concentrated wastes.

  5. Site remediation may expose residents and workers to on-site contaminants byvolatilization and fugitive dust generation. This exposure has the potential to be much higher thanany of the current site-related exposures.


Cease/Reduce Exposure Recommendations

  1. Remove the contaminants in Creek Segments B, C, D, E, and F or restrict access to allthese areas (especially to children).

  2. Remove or contain Site G surface soil contaminants in such a way that they are notreleased to the air or allowed to move by surface runoff. Prevent Site G fires.

  3. Take precautions during site remediation to protect both the workers and residents fromexposure to site contaminants.

  4. Discontinue the use of private or industrial wells that are contaminated or are nearcontaminated groundwater plumes and seal the wells. In addition, no new wells should beinstalled.

  5. Repair the fences. Consider additional actions to prevent site access.

  6. Eliminate the flooding in Creek Segment B. Flood waters have inundated all or parts ofQueeny Avenue for several days at a time. Limited sample data is available on the surface water atCreek Segment B; however, based on the results from the samples taken, acute health effectswould not be expected from brief dermal exposures.

Site Characterization Recommendations

  1. Perform air monitoring at Site G especially at exposure points such as nearby residences,and area businesses and industries to determine airborne exposure to contaminants. Air monitoringwould also be important in determining airborne contaminant concentration during siteremediation.

  2. Take additional surface soil samples in those areas just outside the fence at Site G and inthe yards or the nearest residences in order to determine the levels of dioxins and furans andwhether these areas pose a threat to public health.

  3. Monitor regularly the groundwater contaminant plume to determine movement in off-siteareas. Remediation should remove or at least prevent further migration of the contaminant plume.

  4. Characterize the extent of sediment contaminants in Creek Segments C through F. Theknown concentrations of contaminants in Creek Segments C through F would not be expected toresult in any acute adverse health effects to those children playing in the sediments. However,sampling in the creek Segments is limited and additional samples would be used to moreaccurately determine potential exposures to the sediment contaminants. Restricting access wouldbe recommended in the areas of the creek Segments that contain compounds at levels that maycause chronic adverse health effects, if remedial activities are not expected to begin within the nextfew years.

  5. Test the indoor are of the residences (if any) that are suspected to have indoor aircontamination due to site-related compounds.


Environmental Media Evaluation Guides (EMEGs) are developed for chemicals based on theirtoxicity, frequency of occurrence at National Priority List (NPL) sites, and potential for humanexposure. They are derived to protect the most sensitive populations and are not action levels, butrather comparison values. They do not consider carcinogenic effects, chemical interactions,multiple route exposure, or other media-specific routes of exposure, and are very conservativeconcentration values designed to protect sensitive members of the population.

Reference Dose Media Evaluation Guides (RMEGs) are another type of comparison value derivedto protect the most sensitive populations. They do not consider carcinogenic effects, chemicalinteractions, multiple route exposure, or other media-specific routes of exposure, and are veryconservative concentration values designed to protect sensitive members of the population.

Cancer Risk Evaluation Guides (CREGs) are estimated contaminant concentrations based on aprobability of one excess cancer in a million persons exposed to a chemical over a lifetime. Theseare also very conservative values designed to protect sensitive members of the population.

Maximum Contaminant Levels (MCLs) have been established by USEPA for public watersupplies to reduce the chances of adverse health effects from contaminated drinking water. Thesestandards are well below levels for which health effects have been observed and take into accountthe financial feasibility of achieving specific contaminant levels. These are enforceable limits thatpublic water supplies must meet.

Lifetime Health Advisories for drinking water (LTHAs) have been established by USEPA fordrinking water and are the concentration of a chemical in drinking water that is not expected tocause any adverse non-carcinogenic effects over a lifetime of exposure. These are conservativevalues that incorporate a margin of safety.


Sauget Area 1 Location Map
Figure 1. Sauget Area 1 Location Map

Sauget Area 1 Sites Location Map
Figure 2. Sauget Area 1 Sites Location Map

Air Sample Locations Sauget Area 1
Figure 3. Air Sample Locations Sauget Area 1

Residential Soil Sample Locations Sauget Area 1
Figure 4. Residential Soil Sample Locations Sauget Area 1


ATSDR Glossary of Terms

The Agency for Toxic Substances and Disease Registry (ATSDR) is a federal publichealth agency with headquarters in Atlanta, Georgia, and 10 regional offices in theUnited States. ATSDR's mission is to serve the public by using the best science, takingresponsive public health actions, and providing trusted health information to preventharmful exposures and diseases related to toxic substances. ATSDR is not a regulatoryagency, unlike the U.S. Environmental Protection Agency (EPA), which is the federalagency that develops and enforces environmental laws to protect the environment andhuman health. This glossary defines words used by ATSDR in communications with thepublic. It is not a complete dictionary of environmental health terms. If you havequestions or comments, call ATSDR's toll-free telephone number, 1-888-42-ATSDR (1-888-422-8737).

General Terms

The process of taking in. For a person or an animal, absorption is the process of asubstance getting into the body through the eyes, skin, stomach, intestines, or lungs.

Occurring over a short time [compare with chronic].

Acute exposure:
Contact with a substance that occurs once or for only a short time (up to 14 days)[compare with intermediate duration exposure and chronic exposure].

Additive effect:
A biologic response to exposure to multiple substances that equals the sum of responsesof all the individual substances added together [compare with antagonistic effect andsynergistic effect].

Adverse health effect:
A change in body function or cell structure that might lead to disease or health problems

Requiring oxygen [compare with anaerobic].

Surrounding (for example, ambient air).

Requiring the absence of oxygen [compare with aerobic].

A substance measured in the laboratory. A chemical for which a sample (such as water,air, or blood) is tested in a laboratory. For example, if the analyte is mercury, thelaboratory test will determine the amount of mercury in the sample.

Analytic epidemiologic study:
A study that evaluates the association between exposure to hazardous substances anddisease by testing scientific hypotheses.

Antagonistic effect:
A biologic response to exposure to multiple substances that is less than would beexpected if the known effects of the individual substances were added together [comparewith additive effect and synergistic effect].

Background level:
An average or expected amount of a substance or radioactive material in a specificenvironment, or typical amounts of substances that occur naturally in an environment.

Decomposition or breakdown of a substance through the action of microorganisms (suchas bacteria or fungi) or other natural physical processes (such as sunlight).

Biologic indicators of exposure study:
A study that uses (a) biomedical testing or (b) the measurement of a substance [ananalyte], its metabolite, or another marker of exposure in human body fluids or tissues toconfirm human exposure to a hazardous substance [also see exposure investigation].

Biologic monitoring:
Measuring hazardous substances in biologic materials (such as blood, hair, urine, orbreath) to determine whether exposure has occurred. A blood test for lead is an exampleof biologic monitoring.

Biologic uptake:
The transfer of substances from the environment to plants, animals, and humans.

Biomedical testing:
Testing of persons to find out whether a change in a body function might have occurredbecause of exposure to a hazardous substance.

Plants and animals in an environment. Some of these plants and animals might be sourcesof food, clothing, or medicines for people.

Body burden:
The total amount of a substance in the body. Some substances build up in the bodybecause they are stored in fat or bone or because they leave the body very slowly.

[see Community Assistance Panel.]

Any one of a group of diseases that occur when cells in the body become abnormal andgrow or multiply out of control.

Cancer risk:
A theoretical risk for getting cancer if exposed to a substance every day for 70 years (alifetime exposure). The true risk might be lower.

A substance that causes cancer.

Case study:
A medical or epidemiologic evaluation of one person or a small group of people to gatherinformation about specific health conditions and past exposures.

Case-control study:
A study that compares exposures of people who have a disease or condition (cases) withpeople who do not have the disease or condition (controls). Exposures that are morecommon among the cases may be considered as possible risk factors for the disease.

CAS registry number:
A unique number assigned to a substance or mixture by the American Chemical SocietyAbstracts Service.

Central nervous system:
The part of the nervous system that consists of the brain and the spinal cord.

[see Comprehensive Environmental Response, Compensation, and LiabilityAct of 1980]

Occurring over a long time [compare with acute].

Chronic exposure:
Contact with a substance that occurs over a long time (more than 1 year) [compare withacute exposure and intermediate duration exposure]

Cluster investigation:
A review of an unusual number, real or perceived, of health events (for example, reportsof cancer) grouped together in time and location. Cluster investigations are designed toconfirm case reports; determine whether they represent an unusual disease occurrence;and, if possible, explore possible causes and contributing environmental factors.

Community Assistance Panel (CAP):
A group of people from a community and from health and environmental agencies whowork with ATSDR to resolve issues and problems related to hazardous substances in thecommunity. CAP members work with ATSDR to gather and review community healthconcerns, provide information on how people might have been or might now be exposedto hazardous substances, and inform ATSDR on ways to involve the community in itsactivities.

Comparison value (CV):
Calculated concentration of a substance in air, water, food, or soil that is unlikely tocause harmful (adverse) health effects in exposed people. The CV is used as a screeninglevel during the public health assessment process. Substances found in amounts greaterthan their CVs might be selected for further evaluation in the public health assessmentprocess.

Completed exposure pathway:
[see exposure pathway].

Comprehensive Environmental Response, Compensation, and Liability Act of 1980(CERCLA):
CERCLA, also known as Superfund, is the federal law that concerns the removal orcleanup of hazardous substances in the environment and at hazardous waste sites.ATSDR, which was created by CERCLA, is responsible for assessing health issues andsupporting public health activities related to hazardous waste sites or other environmentalreleases of hazardous substances. This law was later amended by the SuperfundAmendments and Reauthorization Act (SARA).

The amount of a substance present in a certain amount of soil, water, air, food, blood,hair, urine, breath, or any other media.

A substance that is either present in an environment where it does not belong or ispresent at levels that might cause harmful (adverse) health effects.

Delayed health effect:
A disease or an injury that happens as a result of exposures that might have occurred inthe past.

Referring to the skin. For example, dermal absorption means passing through the skin.

Dermal contact:
Contact with (touching) the skin [see route of exposure].

Descriptive epidemiology:
The study of the amount and distribution of a disease in a specified population by person,place, and time.

Detection limit:
The lowest concentration of a chemical that can reliably be distinguished from a zeroconcentration.

Disease prevention:
Measures used to prevent a disease or reduce its severity.

Disease registry:
A system of ongoing registration of all cases of a particular disease or health condition ina defined population.

United States Department of Defense.

United States Department of Energy.

Dose (for chemicals that are not radioactive):
The amount of a substance to which a person is exposed over some time period. Dose is ameasurement of exposure. Dose is often expressed as milligram (amount) per kilogram (ameasure of body weight) per day (a measure of time) when people eat or drinkcontaminated water, food, or soil. In general, the greater the dose, the greater thelikelihood of an effect. An "exposure dose" is how much of a substance is encountered inthe environment. An "absorbed dose" is the amount of a substance that actually got intothe body through the eyes, skin, stomach, intestines, or lungs.

Dose (for radioactive chemicals):
The radiation dose is the amount of energy from radiation that is actually absorbed by thebody. This is not the same as measurements of the amount of radiation in theenvironment.

Dose-response relationship:
The relationship between the amount of exposure [dose] to a substance and the resultingchanges in body function or health (response).

Environmental media:
Soil, water, air, biota (plants and animals), or any other parts of the environment that cancontain contaminants.

Environmental media and transport mechanism:
Environmental media include water, air, soil, and biota (plants and animals). Transportmechanisms move contaminants from the source to points where human exposure canoccur. The environmental media and transport mechanism is the second part of anexposure pathway.

United States Environmental Protection Agency.

Epidemiologic surveillance:
[see Public health surveillance].

The study of the distribution and determinants of disease or health status in a population;the study of the occurrence and causes of health effects in humans.

Contact with a substance by swallowing, breathing, or touching the skin or eyes.Exposure may be short-term [acute exposure], of intermediate duration, or long-term[chronic exposure].

Exposure assessment:
The process of finding out how people come into contact with a hazardous substance,how often and for how long they are in contact with the substance, and how much of thesubstance they are in contact with.

Exposure-dose reconstruction:
A method of estimating the amount of people's past exposure to hazardous substances.Computer and approximation methods are used when past information is limited, notavailable, or missing.

Exposure investigation:
The collection and analysis of site-specific information and biologic tests (whenappropriate) to determine whether people have been exposed to hazardous substances.

Exposure pathway:
The route a substance takes from its source (where it began) to its end point (where itends), and how people can come into contact with (or get exposed to) it. An exposurepathway has five parts: a source of contamination (such as an abandoned business); anenvironmental media and transport mechanism (such as movement throughgroundwater); a point of exposure (such as a private well); a route of exposure (eating,drinking, breathing, or touching), and a receptor population (people potentially oractually exposed). When all five parts are present, the exposure pathway is termed acompleted exposure pathway.

Exposure registry:
A system of ongoing follow-up of people who have had documented environmentalexposures.

Feasibility study:
A study by EPA to determine the best way to clean up environmental contamination. Anumber of factors are considered, including health risk, costs, and what methods willwork well.

Geographic information system (GIS):
A mapping system that uses computers to collect, store, manipulate, analyze, and displaydata. For example, GIS can show the concentration of a contaminant within a communityin relation to points of reference such as streets and homes.

Grand rounds:
Training sessions for physicians and other health care providers about health topics.

Water beneath the earth's surface in the spaces between soil particles and between rocksurfaces [compare with surface water].

Half-life (t½):
The time it takes for half the original amount of a substance to disappear. In theenvironment, the half-life is the time it takes for half the original amount of a substanceto disappear when it is changed to another chemical by bacteria, fungi, sunlight, or otherchemical processes. In the human body, the half-life is the time it takes for half theoriginal amount of the substance to disappear, either by being changed to anothersubstance or by leaving the body. In the case of radioactive material, the half life is theamount of time necessary for one half the initial number of radioactive atoms to changeor transform into another atom (that is normally not radioactive). After two half lives,25% of the original number of radioactive atoms remain.

A source of potential harm from past, current, or future exposures.

Hazardous Substance Release and Health Effects Database (HazDat):
The scientific and administrative database system developed by ATSDR to manage datacollection, retrieval, and analysis of site-specific information on hazardous substances,community health concerns, and public health activities.

Hazardous waste:
Potentially harmful substances that have been released or discarded into the environment.

Health consultation:
A review of available information or collection of new data to respond to a specifichealth question or request for information about a potential environmental hazard. Healthconsultations are focused on a specific exposure issue. Health consultations are thereforemore limited than a public health assessment, which reviews the exposure potential ofeach pathway and chemical [compare with public health assessment].

Health education:
Programs designed with a community to help it know about health risks and how toreduce these risks.

Health investigation:
The collection and evaluation of information about the health of community residents.This information is used to describe or count the occurrence of a disease, symptom, orclinical measure and to evaluate the possible association between the occurrence andexposure to hazardous substances.

Health promotion:
The process of enabling people to increase control over, and to improve, their health.

Health statistics review:
The analysis of existing health information (i.e., from death certificates, birth defectsregistries, and cancer registries) to determine if there is excess disease in a specificpopulation, geographic area, and time period. A health statistics review is a descriptiveepidemiologic study.

Indeterminate public health hazard:
The category used in ATSDR's public health assessment documents when a professionaljudgment about the level of health hazard cannot be made because information critical tosuch a decision is lacking.

The number of new cases of disease in a defined population over a specific time period[contrast with prevalence].

The act of swallowing something through eating, drinking, or mouthing objects. Ahazardous substance can enter the body this way [see route of exposure].

The act of breathing. A hazardous substance can enter the body this way [see route ofexposure].

Intermediate duration exposure:
Contact with a substance that occurs for more than 14 days and less than a year [comparewith acute exposure and chronic exposure].

In vitro:
In an artificial environment outside a living organism or body. For example, sometoxicity testing is done on cell cultures or slices of tissue grown in the laboratory, ratherthan on a living animal [compare with in vivo].

In vivo:
Within a living organism or body. For example, some toxicity testing is done on wholeanimals, such as rats or mice [compare with in vitro].

Lowest-observed-adverse-effect level (LOAEL):
The lowest tested dose of a substance that has been reported to cause harmful (adverse)health effects in people or animals.

Medical monitoring:
A set of medical tests and physical exams specifically designed to evaluate whether anindividual's exposure could negatively affect that person's health.

The conversion or breakdown of a substance from one form to another by a livingorganism.

Any product of metabolism.

Milligram per kilogram.

Milligram per square centimeter (of a surface).

Milligram per cubic meter; a measure of the concentration of a chemical in a knownvolume (a cubic meter) of air, soil, or water.

Moving from one location to another.

Minimal risk level (MRL):
An ATSDR estimate of daily human exposure to a hazardous substance at or belowwhich that substance is unlikely to pose a measurable risk of harmful (adverse),noncancerous effects. MRLs are calculated for a route of exposure (inhalation or oral)over a specified time period (acute, intermediate, or chronic). MRLs should not be usedas predictors of harmful (adverse) health effects [see reference dose].

State of being ill or diseased. Morbidity is the occurrence of a disease or condition thatalters health and quality of life.

Death. Usually the cause (a specific disease, a condition, or an injury) is stated.

A substance that causes mutations (genetic damage).

A change (damage) to the DNA, genes, or chromosomes of living organisms.

National Priorities List for Uncontrolled Hazardous Waste Sites (National PrioritiesList or NPL):
EPA's list of the most serious uncontrolled or abandoned hazardous waste sites in theUnited States. The NPL is updated on a regular basis.

National Toxicology Program (NTP):
Part of the Department of Health and Human Services. NTP develops and carries outtests to predict whether a chemical will cause harm to humans.

No apparent public health hazard:
A category used in ATSDR's public health assessments for sites where human exposureto contaminated media might be occurring, might have occurred in the past, or mightoccur in the future, but where the exposure is not expected to cause any harmful healtheffects.

No-observed-adverse-effect level (NOAEL):
The highest tested dose of a substance that has been reported to have no harmful(adverse) health effects on people or animals.

No public health hazard:
A category used in ATSDR's public health assessment documents for sites where peoplehave never and will never come into contact with harmful amounts of site-relatedsubstances.

[see National Priorities List for Uncontrolled Hazardous Waste Sites]

Physiologically based pharmacokinetic model (PBPK model):
A computer model that describes what happens to a chemical in the body. This modeldescribes how the chemical gets into the body, where it goes in the body, how it ischanged by the body, and how it leaves the body.

A craving to eat nonfood items, such as dirt, paint chips, and clay. Some children exhibitpica-related behavior.

A volume of a substance that moves from its source to places farther away from thesource. Plumes can be described by the volume of air or water they occupy and thedirection they move. For example, a plume can be a column of smoke from a chimney ora substance moving with groundwater.

Point of exposure:
The place where someone can come into contact with a substance present in theenvironment [see exposure pathway].

A group or number of people living within a specified area or sharing similarcharacteristics (such as occupation or age).

Potentially responsible party (PRP):
A company, government, or person legally responsible for cleaning up the pollution at ahazardous waste site under Superfund. There may be more than one PRP for a particularsite.

Parts per billion.

Parts per million.

The number of existing disease cases in a defined population during a specific timeperiod [contrast with incidence].

Prevalence survey:
The measure of the current level of disease(s) or symptoms and exposures through aquestionnaire that collects self-reported information from a defined population.

Actions that reduce exposure or other risks, keep people from getting sick, or keepdisease from getting worse.

Public availability session:
An informal, drop-by meeting at which community members can meet one-on-one withATSDR staff members to discuss health and site-related concerns.

Public comment period:
An opportunity for the public to comment on agency findings or proposed activitiescontained in draft reports or documents. The public comment period is a limited timeperiod during which comments will be accepted.

Public health action:
A list of steps to protect public health.

Public health advisory:
A statement made by ATSDR to EPA or a state regulatory agency that a release ofhazardous substances poses an immediate threat to human health. The advisory includesrecommended measures to reduce exposure and reduce the threat to human health.

Public health assessment (PHA):
An ATSDR document that examines hazardous substances, health outcomes, andcommunity concerns at a hazardous waste site to determine whether people could beharmed from coming into contact with those substances. The PHA also lists actions thatneed to be taken to protect public health [compare with health consultation].

Public health hazard:
A category used in ATSDR's public health assessments for sites that pose a public healthhazard because of long-term exposures (greater than 1 year) to sufficiently high levels ofhazardous substances or radionuclides that could result in harmful health effects.

Public health hazard categories:
Public health hazard categories are statements about whether people could be harmed byconditions present at the site in the past, present, or future. One or more hazard categoriesmight be appropriate for each site. The five public health hazard categories are no publichealth hazard, no apparent public health hazard, indeterminate public health hazard,public health hazard, and urgent public health hazard.

Public health statement:
The first chapter of an ATSDR toxicological profile. The public health statement is asummary written in words that are easy to understand. The public health statementexplains how people might be exposed to a specific substance and describes the knownhealth effects of that substance.

Public health surveillance:
The ongoing, systematic collection, analysis, and interpretation of health data. Thisactivity also involves timely dissemination of the data and use for public healthprograms.

Public meeting:
A public forum with community members for communication about a site.

An unstable or radioactive isotope (form) of an element that can change into anotherelement by giving off radiation.

Any radioactive isotope (form) of any element.

[see Resource Conservation and Recovery Act (1976, 1984)]

Receptor population:
People who could come into contact with hazardous substances [see exposure pathway].

Reference dose (RfD):
An EPA estimate, with uncertainty or safety factors built in, of the daily lifetime dose ofa substance that is unlikely to cause harm in humans.

A systematic collection of information on persons exposed to a specific substance orhaving specific diseases [see exposure registry and disease registry].

Remedial investigation:
The CERCLA process of determining the type and extent of hazardous materialcontamination at a site.

Resource Conservation and Recovery Act (1976, 1984) (RCRA):
This Act regulates management and disposal of hazardous wastes currently generated,treated, stored, disposed of, or distributed.

RCRA Facility Assessment. An assessment required by RCRA to identify potential andactual releases of hazardous chemicals.

[see reference dose]

The probability that something will cause injury or harm.

Risk reduction:
Actions that can decrease the likelihood that individuals, groups, or communities willexperience disease or other health conditions.

Risk communication:
The exchange of information to increase understanding of health risks.

Route of exposure:
The way people come into contact with a hazardous substance. Three routes of exposureare breathing [inhalation], eating or drinking [ingestion], or contact with the skin [dermalcontact].

Safety factor:
[see uncertainty factor]

[see Superfund Amendments and Reauthorization Act]

A portion or piece of a whole. A selected subset of a population or subset of whatever isbeing studied. For example, in a study of people the sample is a number of people chosenfrom a larger population [see population]. An environmental sample (for example, asmall amount of soil or water) might be collected to measure contamination in theenvironment at a specific location.

Sample size:
The number of units chosen from a population or an environment.

A liquid capable of dissolving or dispersing another substance (for example, acetone ormineral spirits).

Source of contamination:
The place where a hazardous substance comes from, such as a landfill, waste pond,incinerator, storage tank, or drum. A source of contamination is the first part of anexposure pathway.

Special populations:
People who might be more sensitive or susceptible to exposure to hazardous substancesbecause of factors such as age, occupation, sex, or behaviors (for example, cigarettesmoking). Children, pregnant women, and older people are often considered specialpopulations.

A person, group, or community who has an interest in activities at a hazardous waste site.

A branch of mathematics that deals with collecting, reviewing, summarizing, andinterpreting data or information. Statistics are used to determine whether differencesbetween study groups are meaningful.

A chemical.

Substance-specific applied research:
A program of research designed to fill important data needs for specific hazardoussubstances identified in ATSDR's toxicological profiles. Filling these data needs wouldallow more accurate assessment of human risks from specific substances contaminatingthe environment. This research might include human studies or laboratory experiments todetermine health effects resulting from exposure to a given hazardous substance.

[see Comprehensive Environmental Response, Compensation, and LiabilityAct of 1980 (CERCLA) and Superfund Amendments and Reauthorization Act (SARA)

Superfund Amendments and Reauthorization Act (SARA):
In 1986, SARA amended the Comprehensive Environmental Response, Compensation,and Liability Act of 1980 (CERCLA) and expanded the health-related responsibilities ofATSDR. CERCLA and SARA direct ATSDR to look into the health effects fromsubstance exposures at hazardous waste sites and to perform activities including healtheducation, health studies, surveillance, health consultations, and toxicological profiles.

Surface water:
Water on the surface of the earth, such as in lakes, rivers, streams, ponds, and springs[compare with groundwater].

[see public health surveillance]

A systematic collection of information or data. A survey can be conducted to collectinformation from a group of people or from the environment. Surveys of a group ofpeople can be conducted by telephone, by mail, or in person. Some surveys are done byinterviewing a group of people [see prevalence survey].

Synergistic effect:
A biologic response to multiple substances where one substance worsens the effect ofanother substance. The combined effect of the substances acting together is greater thanthe sum of the effects of the substances acting by themselves [see additive effect andantagonistic effect].

A substance that causes defects in development between conception and birth. Ateratogen is a substance that causes a structural or functional birth defect.

Toxic agent:
Chemical or physical (for example, radiation, heat, cold, microwaves) agents that, undercertain circumstances of exposure, can cause harmful effects to living organisms.

Toxicological profile:
An ATSDR document that examines, summarizes, and interprets information about ahazardous substance to determine harmful levels of exposure and associated healtheffects. A toxicological profile also identifies significant gaps in knowledge on thesubstance and describes areas where further research is needed.

The study of the harmful effects of substances on humans or animals.

An abnormal mass of tissue that results from excessive cell division that is uncontrolledand progressive. Tumors perform no useful body function. Tumors can be either benign(not cancer) or malignant (cancer).

Uncertainty factor:
Mathematical adjustments for reasons of safety when knowledge is incomplete. Forexample, factors used in the calculation of doses that are not harmful (adverse) to people.These factors are applied to the lowest-observed-adverse-effect-level (LOAEL) or the no-observed-adverse-effect-level (NOAEL) to derive a minimal risk level (MRL).Uncertainty factors are used to account for variations in people's sensitivity, fordifferences between animals and humans, and for differences between a LOAEL and aNOAEL. Scientists use uncertainty factors when they have some, but not all, theinformation from animal or human studies to decide whether an exposure will causeharm to people [also sometimes called a safety factor].

Urgent public health hazard:
A category used in ATSDR's public health assessments for sites where short-termexposures (less than 1 year) to hazardous substances or conditions could result in harmfulhealth effects that require rapid intervention.

Volatile organic compounds (VOCs):
Organic compounds that evaporate readily into the air. VOCs include substances such asbenzene, toluene, methylene chloride, and methyl chloroform.

Other glossaries and dictionaries:

Environmental Protection Agency ( )

National Center for Environmental Health (CDC)( )

National Library of Medicine (NIH)( )

For more information on the work of ATSDR, please contact:

Office of Policy and External Affairs
Agency for Toxic Substances and Disease Registry
1600 Clifton Road, N.E. (MS E-60)
Atlanta, GA 30333
Telephone: (404) 498-0080

Table of Contents The U.S. Government's Official Web PortalDepartment of Health and Human Services
Agency for Toxic Substances and Disease Registry, 4770 Buford Hwy NE, Atlanta, GA 30341
Contact CDC: 800-232-4636 / TTY: 888-232-6348

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