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PUBLIC HEALTH ASSESSMENT

MOUNTAIN PINE PRESSURE TREATING
PLAINVIEW, YELL COUNTY, ARKANSAS


APPENDICES

APPENDIX A: FIGURE

Mountain Pine Pressure Treatment Site Map
Figure 1. Mountain Pine Pressure Treatment Site Map


APPENDIX B: TABLES

Comparison Values Used In Screening Contaminants For Further Evaluation

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,but rather 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 valuederived to protect the most sensitive populations. They do not consider carcinogenic effects,chemical interactions, multiple route exposure, or other media-specific routes of exposure, andare very conservative concentration values designed to protect sensitive members of thepopulation.

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.These are 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 intoaccount the financial feasibility of achieving specific contaminant levels. These are enforceablelimits that public water supplies must meet.

Maximum Contaminant Level Goal (MCLG) is a non-enforceable drinking water health goal.There are no known or anticipated adverse effects on the health of persons drinking watercontaining concentrations at or below the MCLG.

Table 1.

Concentrations of Contaminants of Concern in On-site Soil, Sediment, and Groundwater Samples, Mountain Pine Pressure Treating, Inc. Site, 1997.
Constituent Concentration Range (mg/kg) 1 Health Based Comparison Value (mg/kg)
SOIL AND SEDIMENT
Naphthalene 0.36 1000(EMEG) 2
Dibenzofuran 0.32 230 (RMEG) 3
Pentachlorophenol 10.65 - 202 50 (EMEG)
Phenanthrene 1 - 1.85 30000 (RMEG)
Benzo(a)anthracene 0.28 0.62 (RMEG)
Chrysene 0.25 62 (RMEG)
Arsenic 6.6 - 2182 20 (EMEG)
Cadmium 2.6 - 8.33 10 (EMEG)
Chromium (total) 29.2 - 2984 200 (RMEG)
Copper 8.4 - 2400 2900 (RMEG)
Nickel 14.9 - 50.4 1000 (RMEG)
Lead 30.3 - 211 400 (RMEG)
Zinc 38.5 - 1152 20000 (EMEG)
 
GROUNDWATER
Chromium 0.0006 - 0.0017 0.03 (RMEG)
Copper 0.01 1.3 (MCLG) 4
Lead 0.0015 0.015 (MCL) 5
Zinc 0.012 3 (EMEG)
Bold text indicates a contaminant that exceeded ATSDR's Comparison Value in at least one sample.
1 mg/kg = milligrams per kilogram
2 EMEG = Environmental Media Evaluation Guide
3 RMEG = Reference Dose Media Evaluation Guide
4 MCLG = Maximum Contaminant Level Goal
5 MCL = Maximum Contaminant Level

Table 2.

Polychlorinated Dioxins and Furans Found in On-site Soil Samples, Mountain Pine Pressure Treating, Inc. Site, 1997.
Constituent   Concentrations in parts per million (ppm)
SS-3 SS-4 SS-5 SS-6 SS-7 SS-9 SS-10 SS-11 SS-13
2,3,7,8 TCDD 1 0 0 0 0 0 0 0 0 0
1,2,3,4,6,7,8 HpCDD 2 0 0.0009 0 0 1.76 5.658 0.0088 0.0022 0
1,2,3,4,7,8 HxCDF 3 0 0 0 0.004 0 0 0 0 0
1,2,3,6,7,8 HxCDF 0 0 0 0.003 0.019 0 0 0 0
1,2,3,7,8,9 HxCDF 0 0 0.0032 0.0476 0.27 0 0.0023 0 0
1,2,3,4,6,7,8 HpCDF 4 0 0 0.0071 0.0725 0.33 0 0.003 0.001 0
OCDD 5 0.0025 0.0074 0.2215 2.33 15.139 60.39 0.078 0.0295 0.0025
OCDF 6 0 0.00065 0.01 0.134 0.497 1.176 0.0039 0.0009 0
Total (ppm) 0.0025 0.009 0.2418 2.5911 18.015 67.224 0.096 0.0336 0.0025
  Toxicity Equivalent
Constituent TEF 7                  
2,3,7,8 TCDD 1                  
1,2,3,4,6,7,8 HpCDD 0.01   9.00e-06     1.76e-02 5.66e-02 8.80e-05 2.20e-05  
1,2,3,4,7,8 HxCDF 0.1       4.00e-04          
1,2,3,6,7,8 HxCDF 0.1       3.00e-04 1.90e-03        
1,2,3,7,8,9 HxCDF 0.1     3.20e-04 4.76e-03 2.70e-02   7.36e-07    
1,2,3,4,6,7,8 HpCDF 0.01     7.10e-05 7.25e-04 3.30e-03   2.13e-07 7.10e-08  
OCDD 0.0001 2.50e-07 7.40e-07 2.22e-05 2.33e-04 1.51e-03 1.34e-03 1.73e-06 6.53e-07 5.54e-08
OCDF 0.0001   6.50e-08 1.00e-06 1.34e-05 4.97e-05 1.18e-06 3.90e-09 9.00e-10 0.00e+00
Total (ppm)   2.50e-07 9.81e-06 4.14e-04 6.43e-03 5.14e-02 5.79e-02 9.07e-05 2.27e-05 5.54e-08
Total (ppb) 8   2.50e-04 9.80e-03 4.14e-01 6.43e+00 5.14e+01 1.34e+00 2.68e-03 7.25e-04 5.54e-05
Comparison Value (ppb)   5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02
Bold text indicates a contaminant that exceeded ATSDR's Comparison Value in at least one sample
1 TCDD-tetra-chlorinated dioxin; 2 HpCDD-hepta-chlorinated dioxin; 3 HxCDF-hexa-chlorinated furan; 4 HpCDF-hepta-chlorinated furan; 5 OCDD-octa-chlorinated dioxin; 6 OCDF-octa-chlorinated furan; 7 TEF-toxicity equivalency factor; 8 ppb- parts per billion.

Table 3.

Polychlorinated Dioxins and Furans Found in Sediment Samples, Mountain Pine Pressure Treating Inc. Site, February 22, 1993.
Constituent   Concentrations in parts per million (ppm)
SD-1 SD-2 SD-3 SD-4 SD-5 SD-6 SD-7 SD-8
2,3,7,8 TCDD 1 0 0 0 0 0 0 0 0
1,2,3,6,7,8 HxCDD 2 0 0 0.0022 0.0013 0 0 0.0269 0
1,2,3,7,8,9 HxCDD 0 0.0077 0.0011 0.0009 0 0 0.048 0
1,2,3,4,6,7,8 HpCDD 3 0.0074 0 0.0513 0.0712 0 0 1.176 0.0218
1,2,3,4,7,8 HxCDF 4 0 0 0 0 0 0 0 0
1,2,3,6,7,8 HxCDF 0 0 0 0.0013 0 0 0 0
1,2,3,7,8,9 HxCDF 0 0 0.044 0 0 0 0 0.004
2,3,4,6,7,8 HxCDF 0 0 0.002 0 0 0 0 0
1,2,3,4,6,7,8 HpCDF 5 0 0 0.0756 0.0213 0 0 0 0.0118
1,2,3,4,7,8,9 HpCDF 0 0 0.0018 0 0 0 0 0
OCDD 6 0.0526 1.658 11.155 0.973 0.0078 0.0078 7.13 0.143
OCDF 7 0.0057 0.115 0.096 0.0269 0 0 0.305 0.007
Total (ppm) 0.0657 1.7807 11.429 1.0959 0.0078 0.0078 8.6859 0.1876
  Toxicity Equivalent
Constituent TEF 8                
2,3,7,8 TCDD 1                
1,2,3,6,7,8 HxCDD 0.1     2.20e-04 1.30e-04     2.69e-03  
1,2,3,7,8,9 HxCDD 0.1   7.70e-04 1.10e-04 9.00e-05     4.80e-03  
1,2,3,4,6,7,8 HpCDD 0.01 7.40e-05   5.13e-04 7.12e-04     1.18e-02 2.18e-04
1,2,3,4,7,8 HxCDF 0.1                
1,2,3,6,7,8 HxCDF 0.1       1.30e-04        
1,2,3,7,8,9 HxCDF 0.1     4.40e-03         4.00e-04
2,3,4,6,7,8 HxCDF 0.1     2.00e-04          
1,2,3,4,6,7,8 HpCDF 0.01     7.56e-04 2.13e-04       1.18e-04
1,2,3,4,7,8,9 HpCDF 0.01     1.80e-05          
OCDD 0.0001 5.26e-06 1.66e-04 1.12e-03 9.73e-05 7.80e-07 7.80e-07 7.13e-04 1.43e-05
OCDF 0.0001 5.70e-07 1.15e-05 9.60e-06 2.69e-06     3.05e-05 7.00e-07
Total (ppm)   7.98e-05 9.47e-04 7.34e-03 1.38e-03 7.80e-07 7.80e-07 2.00e-02 7.51e-04
Total (ppb) 9 7.98e-02 9.47e-01 7.34e+00 1.37e+00 7.80e-04 7.80e-04 2.00e+01 7.51e-01
Comparison Value (ppb)   5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02 5.00e-02
Bold text indicates a contaminant that exceeded ATSDR's Comparison Value in at least one sample
1 TCDD-tetra-chlorinated dioxin; 2 HxCDD-hexa-chlorinated dioxin; 3 HpCDD-hepta-chlorinated dioxin; 4 HxCDF-hexa-chlorinated furan; 5 HpCDF-hepta-chlorinated furan; 6 OCDD-octa-chlorinated dioxin; 7 OCDF-octa-chlorinated furan; 8 TEF-toxicity equivalency factor; 9 ppb- parts per billion.

Table 4.

Nimrod Lake Sediment Samples, Mountain Pine Pressure Treating Inc. Site; May 14, 1998.
Constituent Maximum Sediment concentration (mg/kg) 1 Health based comparison value (mg/kg)
Mouth Porter Creek Vicinity of Water Intake
Aluminum 23.3 19.3 100,000 (EMEG) 2
Arsenic 6.7 3.0 20 (RMEG) 3
Barium 0.156 0.137 4000 (RMEG)
Calcium 537 461 NA 4
Chromium 35.8 29.8 200 (RMEG)
Copper ND 0.7 2900 (RMEG)
Iron 29.7 27.5 23000 (RMEG)
Magnesium 1870 1620 NA
Manganese 0.56 0.55 3000 (RMEG)
Nickel 34.9 31.7 1000 (RMEG)
Lead 23.5 26.4 400 (RMEG)
Benzo(a)pyrene 0.18 ND 5 0.1 (CREG) 6
OCDD 7 0.006 0.005 NA
HpCDF 8 0.0048 0.00278 NA
Bold text indicates sample concentration that exceeded comparison value
1 mg/kg = milligrams per kilogram; 2 EMEG = Environmental Media Evaluation Guide; 3 RMEG = Reference Dose Media Evaluation Guide; 4 NA = not applicable (no comparison value has been established); 5 ND = not detected; 6 CREGs = Cancer Risk Evaluation Guides; 7 OCDD-octa-chlorinated dioxin; 8 .HpCDF-hepta-chlorinated furan.

Table 4.

Toxicity Equivalents for Polychlorinated Dioxins and Furans, Nemrod Lake Sediment Samples, Mountain Pine Pressure Treating Inc. Site, May 14, 1998.
Constituent Concentration (mg/kg) 1 TEF 2 TEQ 3 (ppb) 4 Comparison Value (ppb)
OCDD 5 0.006 0.0001 0.000600 0.05
HpCDF 6 0.0048 0.0001 0.000480 0.05
1 mg/kg -milligrams per kilogram; 2 TEF-toxicity equivalency factor; 3 TEQ-Toxicity equivalents (TEQ); 4 ppb-parts per billion; 5 OCDD-octa-chlorinated dioxin; 6 HpCDF-hepta-chlorinated furan.

Table 5.

Nimrod Lake Fish Samples, Mountain Pine Pressure Treating Inc. Site, May 14, 1998
Constituent Maximum fish concentration (mg/kg) 1 from five samples Estimated Ingestion Dose
mg/kg/day 2
Health based comparison dose
mg/kg /day
Mouth Porter Creek Vicinity of Water Intake
Mercury 0.64 0.71 0.02 0.003
(MRL) 3
Benzoic Acid 0.2941 0.3370 0.009 4.0
(RfD) 4
4-chloro-3-methylphenol 0.0434 0.0756 0.002 0.05
(MRL for p-cresols)
Naphthalene 0.0143 0.0085 0.0003 0.02
(MRL)
Phenanthrene 0.0155 ND 0.0005 2.6
(Cancer Effect Level for PAH 5)
Phenol 0.0571 0.0794 0.002 0.003
(NOAEL6 : human)
1 mg/kg- milligrams per kilogram; 2 mg/kg/day- milligrams per kilogram per day; 3 MRL- Minimal Risk Level; 4 RfD- reference dose; 5 PAH- polycyclic aromatic hydrocarbons; 6 NOAEL- no observed adverse effect level.

Table 6.

Off-site Soil and Sediment Samples, Mountain Pine Pressure Treating Inc. Site, Expanded Site Inspection: February 22, 1993.
Constituent Concentration Range (mg/kg) 1 Health Based Comparison Value (mg/kg)
  SOIL SEDIMENT  
Arsenic 7.4 - 14.0 11.4 - 53.3 0.5 (CREG 2)
0.6 (Pica child EMEG 3)
20 (EMEG)
Chromium (total) 26.6 - 38.6 21.8 - 142.0 10 (Pica child EMEG)
200 (RMEG 4)
Copper 9.6 - 17.3 6.4 - 25.9 2900 (RMEG)
Pentachlorophenol ND 5 ND - 1.10 6 (CREG)
50 (EMEG)
1 mg/kg = milligrams per kilogram;2 CREG = Cancer Risk Evaluation Guide; 3 EMEG = Environmental Media Evaluation Guide; 4 RMEG = Reference Dose Media Evaluation Guide; 5 ND = not detected

Table 7.

Exposure Pathways
Pathway Name Contaminants of Concern Source Transport Media Point of Exposure Route of Exposure Exposed Population Time Comments
Completed Exposure Pathway
Off-site soil Arsenic
Chromium
Process Operations Soil Residential yards
School grounds
Ingestion

Local Area residents Past
Present
Future
Data inadequate to assess the extent and magnitude of possible past or present exposures. Off-site soil is considered an indeterminate public health hazard because of limited information.
Potential Exposure Pathway
On-site soil Arsenic
Chromium
Pentachlorophenol
Process Operations Soil Process area Ingestion Trespassers
Workers
Past
Present
Future
Frequency, intensity, and duration of possible exposures considered adequate to result in exposure above levels of health concern. Soil considered to present a public health hazard.
Sediment Arsenic
Chromium
Pentachlorophenol
Process Operations Leachate Porter Creek
Drainage ditches
Ingestion Local Area residents Past
Present
Future
Frequency, intensity, and duration of possible exposures considered inadequate to result in exposure above levels of health concern. Sediment considered to present no apparent public health hazard
Surface Water Arsenic
Chromium
Pentachlorophenol
Benzo[a]pyrene
Process Operations Surface Water Porter Creek
Fourche LaFave River
Nimrod Lake
Ingestion
Dermal Contact
Local Area residents Past
Present
Future
Frequency, intensity, and duration of possible exposures considered inadequate to result in exposure above levels of health concern. Surface water considered to present no apparent public health hazard.
Food chain Benzo[a]pyrene
Arsenic
Beryllium
Manganese
Process Operations Sediment
Fish
Off site Ingestion Local Area Residents Past
Present
Future
Frequency, intensity, and duration of possible exposures considered inadequate to result in exposure above levels of health concern. Food chain considered to present no apparent public health hazard.
Groundwater Arsenic
Chromium
Copper
Pentachlorophenol
Infiltration Groundwater None
Identified
None Identified None Identified Past
Current
Future
We were not able to identify any evidence of past or current human exposure to contaminated groundwater. Groundwater considered to present no public health hazard at this time.


APPENDIX C: DOSE CALCULATIONS

Calculation of Arsenic Exposure Dose
(On-site Soil and Sediment)
Sample Concentration in parts per million 10 kilograms (kg) Child Dose Child Dose Adult Dose Pica Child Dose
1 6.6 0.0002 0.0001 0.0000 0.0029
2 8.5 0.0002 0.0001 0.0000 0.0037
3 13.7 0.0004 0.0001 0.0000 0.0060
4 13.8 0.0004 0.0001 0.0000 0.0060
5 15.4 0.0004 0.0001 0.0000 0.0067
6 15.6 0.0004 0.0001 0.0000 0.0068
7 16.9 0.0005 0.0001 0.0000 0.0074
8 19.4 0.0005 0.0002 0.0000 0.0085
9 36.5 0.0010 0.0003 0.0001 0.0160
10 38.0 0.0011 0.0003 0.0001 0.0166
11 51.5 0.0014 0.0005 0.0001 0.0225
12 77.4 0.0022 0.0007 0.0002 0.0339
13 85.4 0.0024 0.0007 0.0002 0.0374
14 176.0 0.0049 0.0015 0.0004 0.0770
15 187.0 0.0052 0.0016 0.0004 0.0818
16 307.0 0.0086 0.0027 0.0006 0.1343
17 751.0 0.0210 0.0066 0.0015 0.3286
18 894.0 0.0250 0.0078 0.0018 0.3911
19 2027.0 0.0568 0.0177 0.0041 0.8868
20 2117.0 0.0593 0.0185 0.0042 0.9262
21 2182.0 0.0611 0.0191 0.0044 0.9546
           
Mean 430.5 0.0121 0.0038 0.0009 0.1883
Bold text numbers are values that exceeded the ATSDR Health Guidelines
Assumptions:
Child:10 kg ingesting 200 milligrams (mg) soil
Child: 16 kg ingesting 100 mg soil
Adult: 70 kg ingesting 100 mg soil
Pica : 16 kg ingesting 5,000 mg soil
Dose Calculation:
Concentration times Ingestion Rate times Exposure Factor (EF) divided by Body Weight

EF = 0.0000014 (5 days/week for 1 year)

 

Calculation of Chromium Exposure Dose(On-site Soil and Sediment)
Sample Concentration in parts per million 10 kilograms (kg) child Dose Child Dose Adult Dose Pica Child Dose
1 29.2 0.0008 0.0003 0.0001 0.0128
2 35.2 0.0010 0.0003 0.0001 0.0154
3 44.9 0.0013 0.0004 0.0001 0.0197
4 46.5 0.0013 0.0004 0.0001 0.0203
5 48.9 0.0014 0.0004 0.0001 0.0214
6 51.0 0.0014 0.0004 0.0001 0.0223
7 51.0 0.0014 0.0004 0.0001 0.0223
8 62.0 0.0017 0.0005 0.0001 0.0271
9 66.0 0.0018 0.0006 0.0001 0.0289
10 83.8 0.0023 0.0007 0.0002 0.0367
11 115.4 0.0032 0.0010 0.0002 0.0505
12 140.0 0.0039 0.0012 0.0003 0.0613
13 155.0 0.0043 0.0014 0.0003 0.0678
14 156.0 0.0044 0.0014 0.0003 0.0683
15 286.0 0.0080 0.0025 0.0006 0.1251
16 656.0 0.0184 0.0057 0.0013 0.2870
17 715.0 0.0200 0.0063 0.0014 0.3128
18 1747.0 0.0489 0.0153 0.0035 0.7643
19 2100.0 0.0588 0.0184 0.0042 0.9188
20 2904.0 0.0813 0.0254 0.0058 1.2705
21 2984.0 0.0836 0.0261 0.0060 1.3055
           
Mean 594.1 0.0166 0.0052 0.0012 0.2599
Bold text numbers are values that exceeded the ATSDR Health Guidelines
Assumptions:
Child:10 kg ingesting 200 milligrams (mg) soil
Child: 16 kg ingesting 100 mg soil
Adult: 70 kg ingesting 100 mg soil
Pica : 16 kg ingesting 5,000 mg soil
Dose Calculation:
Concentration times Ingestion Rate times Exposure Factor (EF) divided by Body Weight

EF = 0.0000014 (5 days/week for 1 year)



APPENDIX D: GLOSSARY

Absorption:
How a chemical enters a person's blood after the chemical has been swallowed, has come into contact with the skin, or has been breathed in.


Acute Exposure:
Contact with a chemical that happens once or only for a limited period of time. ATSDR defines acute exposures as those that might last up to 14 days.


ATSDR:
The Agency for Toxic Substances and Disease Registry. ATSDR is a federal health agency in Atlanta, Georgia that deals with hazardous substance and waste site issues. ATSDR gives people information about harmful chemicals in their environment and tells people how to protect themselves from coming into contact with chemicals.


Background Level:
An average or expected amount of a chemical in a specific environment. Or, amounts of chemicals that occur naturally in a specific environment.


Cancer:
A group of diseases which occur when cells in the body become abnormal and grow, or multiply, out of control.


Carcinogen:
Any substance shown to cause tumors or cancer in experimental studies.


CERCLA:
See Comprehensive Environmental Response, Compensation, and Liability Act.


Chronic Exposure:
A contact with a substance or chemical that happens over a long period of time. ATSDR considers exposures of more than one year to be chronic.


Comparison Value (CVs):
Concentrations or the amount of substances in air, water, food, and soil that are unlikely, upon exposure, to cause adverse health effects. Comparison values are used by health assessors to select which substances and environmental media (air, water, food and soil) need additional evaluation while health concerns or effects are investigated.


Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA):
CERCLA was put into place in 1980. It is also known as Superfund. This act concerns releases of hazardous substances into the environment, and the cleanup of these substances and hazardous waste sites. ATSDR was created by this act and is responsible for looking into the health issues related to hazardous waste sites.


Concern:
A belief or worry that chemicals in the environment might cause harm to people.


Congener:
A chemical compound closely related to another and exerting similar effects.


Concentration:
How much or the amount of a substance present in a certain amount of soil, water, air, or food.


Dermal Contact:
A chemical getting onto your skin. (see Route of Exposure).


Dose:
The amount of a substance to which a person may be exposed, usually on a daily basis. Dose is often explained as "amount of substance(s) per body weight per day".


Dose / Response:
The relationship between the amount of exposure (dose) and the change in body function or health that result.


Duration:
The amount of time (days, months, years) that a person is exposed to a chemical.


Environmental Contaminant:
A substance (chemical) that gets into a system (person, animal, or the environment) in amounts higher than that found in Background Level, or what would be expected.


Environmental Media:
Usually refers to the air, water, and soil in which chemicals of interest are found. Sometimes refers to the plants and animals that are eaten by humans. Environmental Media is the second part of an Exposure Pathway.


U.S. Environmental Protection Agency (EPA):
The federal agency that develops and enforces environmental laws to protect the environment and the public's health.


Exposure:
Coming into contact with a chemical substance.


Exposure Assessment:
The process of finding the ways people come in contact with chemicals, how often and how long they come in contact with chemicals, and the amounts of chemicals with which they come in contact.


Exposure Pathway:
A description of the way that a chemical moves from its source (where it began) to where and how people can come into contact with (or get exposed to) the chemical.

ATSDR defines an exposure pathway as having 5 parts:

  • Source of Contamination
  • Environmental Media and Transport Mechanism
  • Point of Exposure
  • Route of Exposure
  • Receptor Population

When all 5 parts of an exposure pathway are present, it is called a Completed Exposure Pathway. Each of these 5 terms is defined in this Glossary.


Frequency:
How often a person is exposed to a chemical over time; for example, every day, once a week, twice a month.


Hazardous Waste:
Substances that have been released or thrown away into the environment and, under certain conditions, could be harmful to people who come into contact with them.


Indeterminate Public Health Hazard:
The category is used in Public Health Assessment documents for sites where important information is lacking (missing or has not yet been gathered) about site-related chemical exposures.


Ingestion:
Swallowing something, as in eating or drinking. It is a way a chemical can enter your body (See Route of Exposure).


Inhalation:
Breathing. It is a way a chemical can enter your body (See Route of Exposure).


LOAEL:
Lowest Observed Adverse Effect Level. The lowest dose of a chemical in a study, or group of studies, that has caused harmful health effects in people or animals.


MRL:
Minimal Risk Level. An estimate of daily human exposure by a specified route and length of time -- to a dose of chemical that is likely to be without a measurable risk of adverse, noncancerous effects. An MRL should not be used as a predictor of adverse health effects.


NPL:
The National Priorities List. (Which is part of Superfund.) A list kept by the U.S. Environmental Protection Agency (EPA) of the most serious, uncontrolled or abandoned hazardous waste sites in the country. An NPL site needs to be cleaned up or is being looked at to see if people can be exposed to chemicals from the site.


NOAEL:
No Observed Adverse Effect Level. The highest dose of a chemical in a study, or group of studies, that did not cause harmful health effects in people or animals.


No Apparent Public Health Hazard:
The category is used in ATSDR's Public Health Assessment documents for sites where exposure to site-related chemicals may have occurred in the past or is still occurring but the exposures are not at levels expected to cause adverse health effects.


No Public Health Hazard:
The category is used in ATSDR's Public Health Assessment documents for sites where there is evidence of an absence of exposure to site-related chemicals.


Parts Per Million (ppm):
A unit of measure used to express low concentrations of contaminants. For example, 1 once of Chlorine in 1 million ounces of water is 1ppm. One ppm is comparable to one drop of gasoline in a full sized car's tank full of gas.


PHA:
Public Health Assessment. A report or document that looks at chemicals at a hazardous waste site and tells if people could be harmed from coming into contact with those chemicals. The PHA also tells if possible further public health actions are needed.


Point of Exposure:
The place where someone can come into contact with a contaminated environmental medium (air, water, food or soil). For examples: the area of a playground that has contaminated dirt, a contaminated spring used for drinking water, the location where fruits or vegetables are grown in contaminated soil, or the backyard area where someone might breathe contaminated air.


Population:
A group of people living in a certain area; or the number of people in a certain area.


Public Health Assessment(s):
See PHA.


Public Health Hazard:
The category is used in PHAs for sites that have certain physical features or evidence of chronic, site-related chemical exposure that could result in adverse health effects.


Public Health Hazard Criteria:
PHA categories given to a site which tell whether people could be harmed by conditions present at the site. Each are defined in the Glossary. The categories are:
  • Urgent Public Health Hazard
  • Public Health Hazard
  • Indeterminate Public Health Hazard
  • No Apparent Public Health Hazard
  • No Public Health Hazard

Receptor Population:
People who live or work in the path of one or more chemicals, and who could come into contact with them (See Exposure Pathway).


Reference Dose (RfD):
An estimate, with safety factors (see safety factor) built in, of the daily, life-time exposure of human populations to a possible hazard that is not likely to cause harm to the person.


Risk:
In risk assessment, the probability that something will cause injury, combined with the potential severity of that injury.


Route of Exposure:
The way a chemical can get into a person's body. There are three exposure routes:
  • breathing (also called inhalation)
  • eating or drinking (also called ingestion)
  • getting something on the skin (also called dermal contact).

Safety Factor:
Also called Uncertainty Factor. When scientists don't have enough information to decide if an exposure will cause harm to people, they use "safety factors" and formulas in place of the information that is not known. These factors and formulas can help determine the amount of a chemical that is not likely to cause harm to people.


SARA:
The Superfund Amendments and Reauthorization Act in 1986 amended CERCLA and expanded the health-related responsibilities of ATSDR. CERCLA and SARA direct ATSDR to look into the health effects from chemical exposures at hazardous waste sites.


Sample Size:
The number of people that are needed for a health study.


Sample:
A small number of people chosen from a larger population (See Population).


Semi-Volatile Organic Compounds (SVOCs):
Compounds amenable to analysis by extraction of the sample with an organic solvent. Polycyclic aromatic hydrocarbons, such as naphthalene, phenanthrene, benzo(a)pyrene, and chrysene, comprise one category of SVOCs.


Source (of Contamination):
The place where a chemical comes from, such as a landfill, pond, creek, incinerator, tank, or drum. Contaminant source is the first part of an Exposure Pathway.


Special Populations:
People who may be more sensitive to chemical exposures because of certain factors such as age, a disease they already have, occupation, sex, or certain behaviors (like cigarette smoking). Children, pregnant women, and older people are often considered special populations.


Statistics:
A branch of the math process of collecting, looking at, and summarizing data or information.


Superfund Site:
See NPL.


Toxic:
Harmful. Any substance or chemical can be toxic at a certain dose (amount). The dose is what determines the potential harm of a chemical and whether it would cause someone to get sick.


Toxicology:
The study of the harmful effects of chemicals on humans or animals.


Urgent Public Health Hazard:
This category is used in ATSDR's Public Health Assessment documents for sites that have certain physical features or evidence of short-term (less than 1 year), site-related chemical exposure that could result in adverse health effects and require quick intervention to stop people from being exposed.

Agency for Toxic Substances and Disease Registry Public Health Conclusion Categories
CATEGORY A.
URGENT PUBLIC HEALTH HAZARD

This category is used for sites that pose an urgent public health hazard as the result of short-term exposures to hazardous substances.

Criteria:
Evidence exists that exposures have occurred, are occurring, or are likely to occur in the future; and the estimated exposures are to a substance or substances at concentrations in the environment that, upon short-term exposures (less than 1 year), can cause adverse health effects to any segment of the receptor population. The adverse health effect can be the result of either carcinogenic or noncarcinogenic toxicity from a chemical exposure. For a noncarcinogenic toxic effect, the exposure exceeds an acute or intermediate minimal risk level (MRL) established in the ATSDR Toxicological Profiles or other comparable value; and /or community-specific health outcome data indicate that the site has had an adverse impact on human health that requires rapid intervention; and /or physical hazards at the site pose an imminent risk of physical injury.

CATEGORY B.
PUBLIC HEALTH HAZARD

This category is used for sites that pose a public health hazard as the result of long-term exposures to hazardous substances.

Criteria:
Evidence exists that exposures have occurred, are occurring, or are likely to occur in the future; and the estimated exposures are to a substance or substances at concentrations in the environment that, upon long-term exposures (greater than 1 year), can cause adverse health effects to any segment of the receptor population. The adverse health effect can be the result of either carcinogenic or noncarcinogenic toxicity from a chemical exposure. For a noncarcinogenic toxic effect, the exposure exceeds a chronic MRL established in the ATSDR Toxicological Profiles or other comparable value; and/or community-specific health outcome data indicate that the site has had an adverse impact on human health that requires intervention.

CATEGORY C.
INDETERMINATE PUBLIC HEALTH HAZARD

This category is used for sites with incomplete information.

Criteria:
The limited available data do not indicate that humans are being or have been exposed to levels of contamination that would be expected to cause adverse health effects. However, data or information are not available for all environmental media to which humans may be exposed; and there are insufficient or no community-specific health outcome data to indicate that the site has had an adverse impact on human health.

CATEGORY D.
NO APPARENT PUBLIC HEALTH HAZARD

This category is used for 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.

Criteria:
Exposures do not exceed an ATSDR chronic MRL or other comparable value; and data are available for all environmental media to which humans are being exposed; and there are no community-specific health outcome data to indicate that the site has had an adverse impact on human health.

CATEGORY E.
NO PUBLIC HEALTH HAZARD

This category is used for sites that do not pose a public health hazard.

Criteria:
There is no evidence of current or past human exposure to contaminated media; and future exposures to contaminated media are not likely to occur; and there are no community-specific health outcome data to indicate that the site has had an adverse impact on human health.



Table of Contents

  
 
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