PUBLIC HEALTH ASSESSMENT
Select PCB Exposure Pathways
AGANA POWER PLANT
MONGMONG, GUAM
See Appendix B for definitions of conclusion categories.
VII. PUBLIC HEALTH ACTION PLAN
The public health action plan (PHAP) for the Agana Power Plant recommends actions for ATSDR and other government agencies at and in the vicinity of the site. The PHAP is designed to ensure that this public health assessment not only identifies public health hazards but provides a plan of action designed to mitigate and prevent adverse human health effects resulting from exposure to hazardous substances in the environment. The public health actions completed and to be implemented are as follows:
A. Completed Actions
B. Planned Actions
ATSDR will be preparing another document for the other five issues from the health consultation not covered in this document (see Introduction).
C. Recommended Actions
Charles Grosse
Environmental Health Scientist
Federal Facilities Assessment Branch
Division of Health Assessment and
Consultation
Aimee Tucker Treffeltti
Environmental Health Scientist
Federal Facilities Assessment Branch
Division of Health Assessment and
Consultation
Contributors
Kevin Liske
GIS Analyst
Programs Evaluation Records and Information Services Branch
Division of Health Assessment and Consultation
Reviewers
Sandy Issaacs
Branch Chief
Federal Facilities Assessment Branch
Division of Health Assessment and
Consultation
Gary Campbell
Section Chief, Defense Section
Federal Facilities Assessment Branch
Division of Health Assessment and
Consultation
Diane Jackson
Environmental Engineer
Federal Facilities Assessment Branch
Division of Health Assessment and
Consultation
Allan Susten
Director for Science
Office of the Director
Division of Health Assessment and
Consultation
Carole Hossom
Environmental Health Scientist
Federal Facilities Assessment Branch
Division of Health Assessment and
Consultation
Wallace Sagendorph
Writer/Editor
Office of Programs and External Affairs
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[ATSDR] Agency for Toxic Substances and Disease Registry. 2000b. Health consultation outlining various exposure issues from initial site visit-May 2000 to Mongmong and the Agana Power Plant, Mongmong, Guam. Atlanta: US Department of Health and Human Services.
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US Navy. 2002. Orote landfill site (CTO 236), seafood consumption survey of 3 villages in Agat Bay Area, Guam, U.S.A. Prepared for the Navy by AMEC Earth and Environmental.
US Navy. 2001. Dry well investigation and abandonment Agana Power Plant, Guam. Honolulu: Prepared for the Navy by Earth Tech, Inc.
US Navy. 2000. Draft sampling and analysis plan addendum for subsurface soil and groundwater investigation at the Agana Power Plant, Guam. Honolulu: Prepared for the Navy by Earth Tech, Inc.
US Navy. 1999a. Fact sheet no. 3: Navy performs PCB-impacted soil removal action at former APP.
US Navy. 1999b. Fact sheet no. 5: Navy performs PCB-impacted soil removal action at former agana power plant (APP), Mongmong-Toto-Maite and Agana, Guam.
US Navy. 1999c. Action memorandum for a time-critical removal action at point of interest (POI)-4, POI-6 East, and the Church, Agana Power Plant, Agana, Guam.
US Navy. Final remediation verification report, time-critical removal action of pcb-contaminated soil, Agana Power Plant, Agana, Guam. September 1999d. Agana: Prepared for the Navy by OHM Remediation Services Corporation, Inc.
US Navy. 1999e. Fact sheet no. 11: water flow information and the Agana power plant (APP).
US Navy. 1999f. Draft data package, off-site area Agana power plant abbreviated remedial investigation at the Agana power plant off-site area, Guam. Agana: Prepared for the Navy by Earth Tech, Inc.
US. Navy. 1998a. Fact sheet no. 1: Navy investigates old Agana power plant.
US Navy. 1998b. Fact sheet no. 2: Navy environmental cleanup of former Agana power plant, Mongmong-Toto-Maite and Agana, Guam.
US Navy. 1996. Final remedial investigation for dry cleaning shop, NEX Garage, USS Proteus, and Orote Landfill. Agana: Prepared for the Navy by Ogden Environmental and Energy Services Co., Inc.
Ward PE, Hoffard SH, Davis DA. 1965. Hydrology of Guam, geology and hydrology of Guam, Mariana Islands. Geological survey professional paper 403-H. Reston: US Department of the Interior, US Geological Survey.
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Literature Reviewed
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Figure 1. Site Location Agana Power Plant
Figure 2. Agana Power Plant Drainage Areas
APPENDIX A: POSSIBLE EXPOSURE SITUATIONS FOR PCBS FROM THE AGANA POWER PLANT
| Situation | Conclusion Category* | Recommendations |
| 1. People Eating Foods from Agana Swamp and
River
a) Fish, eels, or snails, including aquatic snails, from Agana Swamp or River have detectable levels of several contaminants, but the contaminant levels are below those that would pose a health hazard. Bacterial contamination has been detected in Agana Swamp; therefore, bacterial contamination of fish is possible. |
a) Chemical Biologic |
a) Because fish, eels, and snails could have biological contaminants, the foods should be thoroughly cooked before eating to avoid gastrointestinal problems, and raw food should not be handled by people who have open cuts or wounds. ATSDR recommends further characterization of biologic hazards in the swamp through sampling. In addition, as funding becomes available, the government of Guam should consider a baseline evaluation of snails and other organisms for biologic hazards. |
| b) PCBs were not detected in fruits and vegetables grown and harvested in the Agana Swamp. Only one sample of taro root was analyzed for dioxins. A detectable level was found, but was below a level that would pose a health hazard. | b) Chemical Past and Current- No Apparent Public Health Hazard |
b) ATSDR concludes that fruits and vegetables grown and harvested in the Agana Swamp do not pose a public health hazard from chemical contaminants. |
| 6. Playing in the Dirt or Runoff Ditches and
Gardening
Soil samples from the two off-site drainage ditches and nearby residential areas show low levels of PCB contamination. Still, the contaminant levels are below those that would pose a health hazard. |
Chemical Past and Current- No Public Health Hazard |
ATSDR concludes that the soils from and around the runoff ditches and in the residential areas are safe to touch during activities such as playing or gardening, and do not pose a health hazard from accidental ingestion. |
| 7. Swimming and Wading in Agana Swamp and
River
The Outfall Drainage Area from the APP leads to the Agana Swamp. Some sediment samples from the Agana Swamp and River have low concentrations of PCBs. These levels are lower than those that would pose a health hazard. In addition, PCBs don't easily dissolve in water and any runoff from the APP would have been diluted by the large volume of water in the swamp. Therefore, touching the water would not have posed a chemical health hazard. However, since the 1960s biological contamination in the swamp has been documented by the U.S. Geological Service (USGS). |
Chemical Past and Current- No Apparent Public Health Hazard Biologic |
ATSDR concludes it was safe to swim and wade in the Agana Swamp and River in the past, and currently it is safe from chemical contamination. Nevertheless, due to the biological contamination, people with open cuts or wounds who swim or wade might have an increased likelihood of infection, and those who accidentally ingest the water could have gastrointestinal problems such as diarrhea and abdominal cramps. |
* See Appendix B
APPENDIX B: ATSDR HAZARD CATEGORIES
| Category | Definition | Criteria |
| 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. | • evidence exists that exposures have occurred, are occurring, or are
likely to occur in the future AND • estimated exposures are to a substance(s) at concentrations in the environment that, upon short-term exposures, can cause adverse health effects to any segment of the receptor population 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 |
| 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. | • evidence exists that exposures have occurred, are occurring, or are
likely to occur in the future AND • estimated exposures are to a substance(s) at concentrations in the environment that, upon long-term exposures, can cause adverse health effects to any segment of the receptor population AND/OR • community-specific health outcome data indicate that the site has had an adverse impact on human health that requires intervention |
| C. Indeterminate (potential) public health hazard | This category is used for sites with incomplete information. | • 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; 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 |
| 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. | • 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 |
| E. No public health hazard | This category is used for sites that do not pose a public health hazard. | • 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 |
APPENDIX C: CALCULATION OF TOTAL DIOXINS AS 2,3,7,8-TCDD TEQ
Dioxins, furans, and dioxin-like PCB congeners are evaluated based on total toxicity equivalency factors (TEF) as related to the most toxic dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). The TEFs are based on known toxicological information for each compound. A total equivalency (TEQ) is calculated by multiplying the chemical concentration by the TEF, and then summing all the values. There are two main sets of TEFs, the International TEFs (I-TEFs), which is used by the EPA, and the World Health Organization TEFs (WHO-TEFs). One of the primary differences between the two methods is that the WHO method uses TEFs for dioxin-like PCB congeners. It is often necessary to calculate the 2,3,7,8-TCDD TEQ using both methods because comparison values may be expressed as either I-TEQ or WHO-TEQ. The I-TEFs and the WHO-TEFs are listed in Table C-1.
Table C-1: Total Equivalency Factors (TEFs) for Dioxins, Furans, and PCB-like Congeners
|
Compound |
WHO-TEF |
I-TEF |
| 1,2,3,4,6,7,8,9-octachlorodibenzofuran | 0.0001 | 0.001 |
| 1,2,3,4,6,7,8-heptachlorodibenzofuran | 0.01 | 0.01 |
| 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin | 0.01 | 0.01 |
| 1,2,3,4,7,8,9-heptachlorodibenzofuran | 0.01 | 0.01 |
| 1,2,3,4,7,8-hexachlorodibenzofuran | 0.1 | 0.1 |
| 1,2,3,4,7,8-hexachlorodibenzo-p-dioxin | 0.1 | 0.1 |
| 1,2,3,6,7,8-hexachlorodibenzofuran | 0.1 | 0.1 |
| 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin | 0.1 | 0.1 |
| 1,2,3,7,8,9-hexachlorodibenzofuran | 0.1 | 0.1 |
| 1,2,3,7,8,9-hexachlorodibenzo-p-dioxin | 0.1 | 0.1 |
| 1,2,3,7,8-pentachlorodibenzofuran | 0.05 | 0.05 |
| 1,2,3,7,8-pentachlorodibenzo-p-dioxin | 1 | 0.5 |
| 2,3,4,6,7,8-hexachlorodibenzofuran | 0.1 | 0.1 |
| 2,3,4,7,8-pentachlorodibenzofuran | 0.5 | 0.5 |
| 2,3,7,8-tetrachlorodibenzofuran | 0.1 | 0.1 |
| 2,3,7,8-tetrachlorodibenzo-p-dioxin | 1 | 1 |
| octachlorodibenzo-p-dioxin | 0.0001 | 0.001 |
| PCB-105 | 0.0001 | NA* |
| PCB-114 | 0.0005 | NA |
| PCB-118 | 0.0001 | NA |
| PCB-123 | 0.0001 | NA |
| PCB-126 | 0.1 | NA |
| PCB-156 | 0.0005 | NA |
| PCB-157 | 0.0005 | NA |
| PCB-167 | 0.00001 | NA |
| PCB-169 | 0.01 | NA |
| PCB-189 | 0.0001 | NA |
| PCB-77 | 0.0001 | NA |
| PCB-81 | 0.0001 | NA |
*NA = not applicable
APPENDIX D: INFORMATION ON HOW ATSDR ASSESSES EXPOSURE
What is meant by exposure?
People can only be exposed to a chemical if they come in contact with that chemical. Contact (exposure) can occur by breathing, eating, or drinking a substance containing the contaminant or by skin contact with a substance containing the contaminant.
How do ATSDR scientists determine which exposure situations and contaminants to evaluate?
ATSDR's public health assessments are exposure, or contact, driven. Chemical contaminants disposed of or released into the environment have the potential to cause adverse health effects under certain conditions. That said, however, a release does not always result in exposure.
ATSDR scientists evaluate site conditions to determine if people could have been (a past scenario), are (a current scenario), or will be (a future scenario) exposed to site-related contaminants. When evaluating exposure pathways, ATSDR identifies whether exposure to contaminated media (soil, water, air, waste, or biota) has occurred, is occurring, or will occur through ingestion, dermal (skin) contact, or inhalation.
If exposure was or is possible, ATSDR applies a weight-of-evidence approach as to whether people might develop adverse health effects. First, ATSDR scientists select contaminants for further evaluation by comparing them against health-based values. Comparison values are developed by ATSDR from scientific literature available on exposure and health effects. These comparison values are derived for each of the different media and reflect the estimated contaminant concentration that is not likely to cause adverse health effects for a given chemical, assuming a standard daily contact rate (e.g., amount of water or soil consumed or amount of air breathed) and body weight. Comparison values are not thresholds for adverse health effects. ATSDR comparison values establish contaminant concentrations many times lower than levels at which no effects have been observed in experimental animals or human epidemiological studies. Some of the comparison values used by ATSDR scientists include ATSDR's environmental media evaluation guides (EMEG), reference dose media guides (RMEG), USEPA's cancer slope factors, USEPA's reference doses (RfD), and ATSDR's minimal risk levels (MRLs).
If someone is exposed, will they get sick?
Exposure does not always result in harmful health effects. The type and severity of health effects that occur in an individual from contact with a contaminant depend on the exposure concentration (how much), the frequency duration or both of an exposure (how long), the route or pathway of exposure (breathing, eating, drinking, or skin contact), and the multiplicity of exposure (combination of contaminants). Once exposure occurs, characteristics such as age, sex, nutritional status, genetics, life style, and health status of the exposed individual influence how the individual absorbs, distributes, metabolizes, and excretes the contaminant. Together, these factors and characteristics determine the health effects that could occur as a result of exposure to a contaminant in the environment.
There is considerable uncertainty about the true level of exposure to environmental contamination. To account for this uncertainty and to be protective of public health, ATSDR scientists typically use high-end, worst-case exposure level estimates as the basis for determining whether adverse health effects are possible. These estimated exposure levels usually are much higher than those to which people are really exposed. If the exposure levels indicate that adverse health effects are possible, then a more detailed site-specific review of exposure combined with scientific information from the toxicological and epidemiological literature about the health effects from exposure to hazardous substances is performed. Considering all of this weight-of-evidence information, ATSDR makes a determination whether adverse health effects are likely.
More information about the ATSDR evaluation process can be found in ATSDR's Public Health Assessment Guidance Manual at http://www.atsdr.cdc.gov/HAC/HAGM or by contacting ATSDR at 1-888-42ATSDR (1-888-422-8737).
APPENDIX E: EXPOSURE EVALUATION METHODOLOGY AND ASSUMPTIONS
This appendix details the assumptions and calculations that ATSDR used to estimate potential exposure levels from consumption of contaminated fish, eels, and snails and soil. To be protective and account for the uncertainty surrounding how representative the exposure factors are for the residents of Mongmong, ATSDR used health-protective assumptions to estimate the reasonable maximum exposure level. This estimate calculates a daily exposure dose in milligrams of contaminant per kilogram body weight (mg/kg/day). To remain protective of public health, it is intentionally protective and likely overestimates the amount of chemical exposure from eating fish, eels, and snails and contacting soil.
The PCBs were evaluated by adding the concentrations for Aroclors 1248, 1254, and 1260. The semivolatile compounds making up the dioxins were evaluated by multiplying each dioxin concentration by its toxic equivalency factor (TEF) based on its potency relative to 2,3,7,8 tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). The adjusted concentrations of dioxins were added together and evaluated as one total concentration, the 2,3,7,8-TCDD toxic equivalency (TEQ). Appendix C has more information about calculating the 2,3,7,8-TCDD TEQ.
We calculated an estimated dose for PCBs and dioxins using the mean value for each type of fish, eels, or snails sampled or for each soil area. For chemicals not detected, the concentration level was given a value of zero. For calculating cancer risk estimates, ATSDR used USEPA's cancer slope factor for oral doses and then compared those estimates to a risk level of 0.0001. The risk level of 0.0001 (1/10,000) was used because it reflects realistic human exposures; however, risk levels are theoretical and actual risks may be as low as zero. For screening non-cancer effects, the estimated doses were compared to ATSDR's minimum risk level (MRL) for the corresponding chemical. The MRL is derived from the lowest observed adverse effect level (LOAEL) identified in the scientific literature by dividing the LOAEL by a safety factor to protect sensitive groups and account for differences between humans and animals in response to exposure. The scientific evidence on PCBs and dioxins was also reviewed to determine the likelihood of finding adverse health effects in children, pregnant women, and other adults.
Formulas Used to Calculate Potential Exposure Dose
The potential exposure doses for non-cancer health effects and cancer effects are calculated using the following equation:
Formula Used to Calculate Amount of Meals per Month
Dose=EPA's reference dose
Fish, Eels, and Snails Exposure Dose Assumptions
The Navy conducted a seafood consumption survey in Piti, Agat, and Santa Rita (US Navy 2002). The results indicated that the average person ate a meal size of 8.9 ounces (252 grams) of fish 8.4 times per month, or 2.5 ounces (70.5 grams) of fish per day. ATSDR used these values from the survey to calculate exposure dose. The Navy's seafood consumption survey did not collect information about the ingestion rates of children. So ATSDR estimated that a high-end child consumer eats half the amount of adults, or 1.25 ounces (35.25 grams) of fish per day. For the general U.S. population, the USEPA has estimated that on average people consume 20.1 grams/day for all fish and shellfish (EPA 1997b). For Native American subsistence populations, the 95th percentile per capita fish intake rate is estimated at 170 grams/day (Toy 1996). With these consumption comparisons, ATSDR believes that the consumption values used to calculate exposure doses are protective of human health. Table E-1 lists additional assumptions used in calculations.
Table E-1: Fish, Eels, and Snails Exposure Dose Assumptions
| Parameter | Abbreviation | Child | Adult |
| Chemical Concentration | C | specific to location | specific to location |
| Ingestion Rate | IR | 35.25 g/day | 70.5 g/day |
| Exposure Frequency | EF | 365 days/year | 365 days/year |
| Exposure Duration | ED | 10 years | 40 years |
| Body Weight | BW | 15.3 kg | 72 kg |
| Averaging Time | AT | 365 days | 365 days |
| Averaging Duration Carcinogens | AD | 70 | 70 |
| Averaging Duration Non-carcinogens | AD | ED | ED |
| Average Meal Size | M | 0.126 kg | 0.252 kg |
Table E-2 is an example of calculated non-cancer effects doses for PCB exposure from eating fish, eels, and snails from the Agana Swamp and River.
Table E-2. Estimated PCB Exposure Dose Levels from Eating Fish, Eels, and Snails from the Agana Swamp and River
Non-cancer effects
| Type of fish | Adult Dose (mg/kg/day) | Child Dose (mg/kg/day) | MRL (mg/kg/day) | Average PCB conc. (mg/kg) |
| Apple snail | 0.0000024 | 0.0000057 | 0.00002 | 0.0025 |
| Tilapia fillet | 0.00013 | 0.000048 | 0.00002 | 0.14 |
| Catfish fillet | 0.000021 | 0.00014 | 0.00002 | 0.021 |
| Eel fillet | 0.000058 | 0.00031 | 0.00002 | 0.059 |
These assumptions were also used to calculate the number of meals an adult or child could eat in a month without exceeding USEPA's health protective reference dose (RfD) (see Table 5).
Soil Exposure Dose Assumptions
ATSDR placed people into five groups based on age and relative body weight. The amount of soil each age group would ingest was intentionally overestimated. The groups are (1) infants age 6 months to 3 years exhibiting pica behavior by eating soil, (2) infants age 6 months to 3 years not exhibiting pica behavior, (3) young children age 3 to 12 years old, (4) teenagers age 12 to 18 years old, and (5) adults—including pregnant women and the elderly. Table E-3 lists additional assumptions used in the calculations. Pica children were evaluated for acute rather than long-term exposures because pica behavior generally involves ingestion of a large amount of soil during single day rather than smaller amounts over a longer period of time (Calabrese 1997).
Table E-3: Soil Exposure Dose Assumptions
| Parameter | Pica Child 6 mos. to 3 years | Non-pica Child 6 mos. to 3 years | Child 3 to 12 years | Teenager 12 to 18 years | Adult | |
| Chemical Concentration | C | specific to location | specific to location | specific to location | specific to location | specific to location |
| Ingestion Rate | IR | 1000 mg/day | 100 mg/day | 100 mg/day | 100 mg/day | 50 mg/day |
| Exposure Frequency | EF | 1 day | 365 days/year | 365 days/year | 365 days/year | 365 days/year |
| Exposure Duration | ED | 1 day | 2.5 years | 9 years | 6 years | 30 years |
| Body Weight | BW | 15.3 kg | 15.3 kg | 28 kg | 50 kg | 71.8 kg |
| Averaging Time | AT | 1 day | 365 days/year | 365 days/year | 365 days/year | 365 days/year |
| Averaging Duration Carcinogens | AD | NA* | 2 years | 9 years | 6 years | 70 years |
| Averaging Duration Non-carcinogens | AD | ED | ED | ED | ED | ED |
*NA = Not applicable
Table E-4 is an example of calculated non-cancer effects doses for PCB exposure from accidentally ingesting soil while gardening or playing in the West Drainage area and residential area. Note that exposure dose for the West Drainage area represents past exposure because the 3.69 mg/kg average soil concentration is the preremediation concentration. Current exposure doses from soil are much lower with the postremediation average of 0.53 mg/kg in the West Drainage area.
Table E-4. Estimated PCB Exposure Dose Levels from
Accidentally Ingesting Soil
While Gardening or Playing - Non-cancer effects
|
Location* |
Dose (mg/kg/day) |
MRL (mg/kg/day) | Average PCB conc. (mg/kg) | ||||
| Pica Child 6 mos. to 3 years | Non-Pica Child 6 mos. to 3 years | Child 3 to 12 years | Teenager 12 to 18 years | Adult | |||
| Residential Area | 4.2 x 10-6 | 4.2 x 10-7 | 2.3 x 10-7 | 1.3 x 10-7 | 4.5 x 10-8 | 2.0 x 10-5 | 0.065 |
| West Drainage Area | 1.2 x 10-4 | 2.4 x 10-5 | 1.3 x 10-5 | 7.4 x 10-6 | 2.6 x 10-6 | 2.0 x 10-5 | 3.69 |
*See Figure 2
APPENDIX F: FREQUENTLY DISCUSSED HEALTH EFFECTS FROM PCB EXPOSURES
Skin Effects
Effects from overexposure in occupational settings, which are higher levels than generally seen in the environment, include chloracne, hyperpigmentation of the nails and skin, and skin irritation. These symptoms generally disappear when PCB exposure stops (ATSDR 2000c).
Developmental Effects
There are no reports of structural birth defects in humans caused by PCB exposure. Several recent studies suggest that children born to mothers who ate PCB-contaminated fish during their pregnancies might have had an increased risk of developing subtle (i.e., not easily observable) nervous system delays (e.g., abnormal reflexes, motor immaturity, deficits in memory, learning, and IQ). In some cases, these delays persisted into adolescence, but in most cases they returned to normal within the first 2 to 4 years. These effects were only seen when large populations were studied and tended to be within the normal range of variation. The clinical relevance of these effects, particularly for individual children, is unknown. Other studies, however, did not find these associations, and any changes that were observed disappeared upon later study (ATSDR 2000c).
Cancers
Some human studies suggest that PCBs are carcinogenic—based on indications of cancer in areas such as the liver, biliary tract, intestines, and skin (ATSDR 2000c). Studies have shown that animals exposed to high levels of PCBs over their lifetimes developed liver and kidney tumors (ATSDR 2000c). Based on observed cancers in animals, the Department of Health and Human Services concluded that PCBs might reasonably be anticipated to be carcinogens (ATSDR 2000c). Both the U.S. Environmental Protection Agency and the International Agency for Research on Cancer have determined that PCBs are probably carcinogenic to humans (ATSDR 2000c). This designation means that a clear cause-and-effect relationship has not been established in humans, but there is sufficient evidence to take precautions about exposure to this chemical. ATSDR continues to support recommendations by health and regulatory agencies to reduce exposure to PCBs.
APPENDIX G: REPORTED HEALTH CONDITIONS IN MONGMONG RESIDENTS
During ATSDR's community meetings, people wanted more information on the following health issues and whether they were related to PCB exposures from the Agana Power Plant.
ATSDR's evaluation found that none of these health concerns were related to PCB exposure. Information on the known associations for these health issues and other information is provided in the following fact sheets.
Click here to view Appendix G in PDF format (PDF, 343KB)
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