Skip directly to search Skip directly to A to Z list Skip directly to site content





Figure 1. Site Plot Plan

Figure 2. Schematic of process monitoring



Comments were received on this health consultation from a Lock Haven resident and from EPA Region III. EPA comments were responses or explanations for a number of issues raised in this consultation. Their comments are attached. If changes were made based on their comments, ATSDR has added a response noting those changes. We also added responses to several of the issues where further explanation of ATSDR's position was needed.

The resident submitted twenty-two newspaper articles and two reports from the Government Accountability Project for our review and requested that we also consider the report issued by Bob Martin, the EPA-Washington ombudsman. She also requested that ATSDR collect health information from the local hospitals on cancers, lung problems, skin problems, and birth problems including difficulties, defects, deaths, and miscarriages. She requested that this data be used as a baseline for conducting a longitudinal health study of the Lock Haven area. The commenter also questioned whether history would support that incineration is a safe technology or that it is a dangerous practice that should be banned.

Occupational and community health studies have been conducted for the Lock Haven area for a number of years to evaluate health outcomes related to the workers' and community's exposure to b-naphthylamine (BNA) resulting from the Drake Chemical plant's operation and production of BNA. Further health studies do not seem warranted at this time. Because of limited resources and the expenses involved in conducting a longitudinal health study, ATSDR has developed criteria for when it is appropriate to conduct a health study. One of the key criteria is that there should be documented community exposure to contaminants at levels of public health concern. In the draft Health Consultation #3, ATSDR evaluates the potential public health effects from the incinerator. In that consultation, ATSDR concluded that the community is not likely to experience adverse health outcomes due to exposure to contaminants from the Drake Chemical Superfund site or emissions from the incinerator being used to remediate that site. If new information is provided that indicates exposure of the public to contaminants at levels of health concern, the Agency will re-evaluate the need for conducting additional health studies in the Lock Haven community.

Incineration is a technology that has been around for hundreds of years. History so far has not indicated that incineration is a dangerous practice that should be banned. There has been at least one documented instance where a commercial hazardous waste incineration facility which had no air pollution control equipment and operated under poor combustion practices did cause adverse health effects in nearby residents (see Caldwell Systems, Inc. discussion in Appendix B). However, stack testing and/or ambient air monitoring at many other incinerators have not indicated releases at levels of health concern. In the last 15 - 20 years, hazardous waste incineration practices and facilities in the USA have in general improved dramatically, so it is unlikely that history will find that the newer facilities are so dangerous that they should be banned. Appendix B contains a summary of the health studies related to incineration that ATSDR has funded.

The Preliminary Report Regarding Shakedown and Trial Burn Activities at the Drake Chemical Superfund Site in Lock Haven, Pennsylvania, dated October 18, 1996, by the Government Accountability Project raised the following issues. Each issue is addressed here, no changes were made in the text of the health consultation.

Issue 1: When the mini-risk burn sampling for polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) and manganese was conducted soil had only been burned for four hours before the sampling began. The authors were concerned that this was insufficient time to establish a PCDD/F equilibrium due to the hysteresis effect that has been reported by several researchers. Therefore, that data might be biased low.

ATSDR Response: We did not use the mini-risk burn data when evaluating the public's exposure to PCDD/Fs and manganese in our Health Consultation #3. We used ambient air samples collected at community monitors for two years and stack samples taken during the full risk burn conducted in January 1997. The full risk burn was conducted after several months of burning contaminated soil, so the hystereses effect should not be an issue with that data.

Issue 2: On October 9, 1996, the waste feed shut-off did not occur automatically within one hour of the pH falling less than 6.0 like it should have. The issue was raised that the increase in HCl could have caused an increase in PCDD/F formation.

ATSDR Response: It is our understanding that strict measures were put into place because of this event to assure that operators assure compliance with the Pennsylvania specified operating conditions and do not override automatic waste feed shut-offs (AWFSOs). To our knowledge no such events have occurred since then. Health Consultation #2 endorsed the AWFSOs established by the state of Pennsylvania, which includes the one-hour delay on low pH in the scrubber, because there is an immediate AWFSO if the inlet temperature to the scrubber exceeds 250 oF. Since this AWFSO will prevent the scrubber temperature from getting into the dioxin and furan formation temperature range, an increase in hydrogen chloride (HCl) caused by a pH less than six should not increase dioxin or furan emissions. A number of researchers have found that PCDD/F formation does not increase with increased HCl concentrations; however it does correlate with chlorine (Cl2) concentrations and the presence of copper and temperatures between 480 oF and 660 oF (1).

Issue 3: The issue was raised as to whether PCDD/F would increase during an event such as the thermal relief valve opening on October 11, 1996, if contaminated soil was being processed at the time. The point was made that the gases would be exiting at elevated temperatures and cooled in the environment through the dioxin formation temperature range.

ATSDR Response: Fundamental laws of chemistry state that the precursor chemicals (products of incomplete combustion) must come in contact with each other for a sufficient period of time to react and form other chemicals such as dioxins or furans. This has been shown to occur in post combustion equipment where gases remain for several seconds in the 480oF to 660oF dioxin and furan formation temperature range. However, when the thermal relief valve opens and the hot gases are vented to the atmosphere, the gases are not confined and the products of incomplete combustion/reactants are not likely to be in close proximity to each other. Furthermore, they will quickly cool to ambient temperature so it is highly unlikely that the necessary reactants will be in contact with each other for several seconds in the ambient air in the necessary temperature range. Therefore, it is highly unlikely that an increase in dioxin and furan formation would occur during a thermal relief valve opening.

Issue 4: The authors pointed out mechanical problems that have occurred.

ATSDR Response: All mechanical devices (even brand new cars) have problems. The fact that problems have occurred does not affect any of the conclusions or recommendations in Health Consultation #3. The most important issue related to mechanical problems is did that event cause public exposure to chemicals at levels of health concern? Health Consultation #3 evaluates the data from the off-site community ambient air monitors and discusses the potential health impacts based on that data.

Issue 5: Several regulatory issues were raised to EPA in this document.

ATSDR Response: ATSDR is not a regulatory agency and will only address health issues related to the Drake site.

The Government Accountability Project Preliminary Report Number 2, Drake Chemical Superfund Site, Lock Haven, Pennsylvania dated January 28, 1997, raised several additional issues. Each issue is addressed here, no changes were made in the text of the health consultation.

Issue #1: The laboratory has analytical problems with the test method being used to measure ambient concentrations of beta-naphthyl amine.

ATSDR Response: ATSDR Health Consultation #1 identified these same problems and recommended that EPA find a better method. Health Consultation #3 also addresses this issue.

Issue #2: Was burned ash mixed with the contaminated soil that was burned during the trial burn and risk burns in January 1997?

ATSDR Response: ATSDR inquired about the alleged occurrence of mixing burned ash with on-site contaminated soil. It is ATSDR's understanding that during the optimization period after October 3, 1996, that the previously burned ash was placed on top of the contaminated soil stockpile due to space constraints on-site. The previously treated ash is visibly different in color and texture from the contaminated soil, so it is possible to see if previously treated ash is brought into the feed building. The ash resulting from this testing is of a discernable color and texture that can be differentiated from the contaminated on-site soil. Ash was said to be removed from the stockpile, prior to the use of the contaminated soil for the trial burn tests. This occurred approximately on January 2, 1997. Mr. Steve Jones, the TAG representative, has investigated this occurrence. The trial burns did not occur until January 20, 1997. On that date, two U.S. Army Corp of Engineer employees inspected the feed building to assure that no previously treated ash was present. It is also ATSDR's understanding that Mr. Valentine, who originally brought up this issue was no longer employed at the Drake site past November 30, 1996, so it is unclear how he would have knowledge of what was burned during the January 1997 trial burns. ATSDR is unable to prove or disprove soil mixing, but it appears that reasonable precautions were in place to assure that only contaminated on-site soils were fed into the incinerator during the trial burns.

Issue #3: The bottom ash samples for both trial burn runs on 25 January 1997, should be considered invalid because of alleged chain-of-custody violations.

ATSDR Response: Since the public is not exposed to the bottom ash, chain-of-custody of the bottom ash samples is not a public health concern. This issue will not be addressed by ATSDR.

Issue #4: Beer drinking on-site is alleged to have occurred on 27 January 1997.

ATSDR Response: ATSDR agrees that beer drinking should not be allowed on the Drake site or any other job site.

Issues #5 and #6 are comments regarding EPA procedural issues; not public health issues. They will not be addressed here.

ATSDR has received and reviewed EPA Ombudsman Bob Martin's draft report and considered his findings. Some of these issues have already been addressed in ATSDR's Health Consultations #1 and #2, including review of the trial burn risk assessment, detection problems with BNA, weather data availability, and site operations. Other issues have been discussed with EPA and will be addressed in the third health consultation, after the data have been reviewed.

Twenty-two newspaper articles were reviewed to determine if they raised any additional issues that are relevant to Health Consultation #2. None were specifically related to this consultation, however quite a few articles raised issues related to the potential for public health effects due to incinerator emissions. This issue is addressed in Health Consultation #3. Several articles also raised the issue of soil blowing off-site. This issue is also addressed in Health Consultation #3. A couple of articles discussed an odor problem that existed in 1995. Apparently that problem has abated since there are no recent articles regarding this issue and we have not noticed a strong odor problem during any of our site visits over the last couple of years. One article referenced an ATSDR health study that found increased neurological and respiratory symptoms among residents who lived near or downwind of an unnamed hazardous waste incinerator. The author suggested that this is what the residents of Lock Haven could expect to happen to them. That health study was a symptom and disease prevalence study conducted in the community around the Caldwell Systems incinerator in North Carolina. That incinerator had been in operation for a number of years without any air pollution control equipment. It was a very poorly run facility, that burned some very toxic Navy wastes under conditions that were indicative of incomplete combustion. The results of that study are not relevant to a state-of-the-art incinerator like the Drake Chemical incinerator treating soil contaminated with parts per million concentrations of chemicals rather than pure products. Other issues raised in these articles which are not within ATSDR's jurisdiction to address are EPA regulatory and legal issues related to the AIR lawsuit, whether the EPA record of decision should be reopened, and contracting costs.



Comment 1: Modeling for potential acute effects should reflect the maximum hourly and maximum daily ambient concentrations.

EPA Response: The air quality modeling for acute effects will utilize the maximum hourly estimated emissions for the normal operations of the incinerator. The modeling will utilize the maximum estimated emissions to determine the annual average ambient concentrations for each pollutant expected to be emitted from the incinerator. As the incinerator is not expected to operate in a fashion that would generate the maximum emissions, the maximum values provide the most conservative approach for the modeling and would overestimate the predicted ambient concentrations and resultant deposition rates.

Comment 2: A comparison of the Williamsport wind data and the actual site-specific wind data for the months that the data are available will provide additional scientific support to the use of the Williamsport meteorological data. A time histogram or auto-correlation may be useful for comparing the two data sets.

EPA Response: A comparison of the Williamsport, PA and onsite meteorological data is presented in Section 4.1 of Volume III of the Drake Chemical Site Incinerator Trial Burn Risk Assessment. A series of monthly wind roses for each data set has been developed to allow for a side-by-side comparison of the wind patterns between Lock Haven and Williamsport, PA.

ATSDR Response: The wind roses do not adequately address our comments; therefore, no changes were made.

Comment 3: The use of 5 years of meteorological data will help assure that likely worst case public exposure concentrations are part of the evaluation.

EPA Response: One (1) year of a combined onsite and Williamsport, PA meteorological data is used in the air quality modeling analysis for the full operation risk assessment. This approach maximizes the influence of local conditions on the meteorological modeling. The use of the combined database maximizes the available and quality assured onsite data for the air quality modeling. However, four and one-half (4.5) years of Williamsport data were also evaluated to ensure that temporal changes in the meteorological data were considered in the risk assessment. This combined data set, including the six months of local Lock Haven data with the four and on-half years of Williamsport data, will be evaluated in a sensitivity analysis in Section 8 of the current risk assessment for full operations.

Comment 4: Are there other sources of local meteorological data, such as the Piper Memorial Airport, the state college, other industrial air sources, river and stream flow stations, etc.? A definitive statement as to the unavailability or unsuitability of any such data (and what attempts were made to locate other local data sources) would strengthen the full operation risk assessment.

EPA Response: WESTON has investigated other possible sources of meteorological data in the Lock Haven, PA data and there are no known sources of data meeting the siting or data requirements for air quality modeling. A statement on the unavailability of local meteorological data will be added to the full operation risk assessment.

Comment 5: The actual number of receptors used in the modeling for the trial burn is unclear. If more than one model is used in the operational risk assessment, ensure that the same receptors are used in each of the models.

EPA Response: A total of 8,571 receptors were utilized in the air quality modeling analysis. A figure displaying the location of these receptors is Figure 2.5-1 of Volume III of the June 1996 risk assessment. The same receptor grid was used with the ISC3 and CALPUFF models.

ATSDR Response: In the Emissions Modeling , this comment (the fifth bullet) was deleted. EPA has clarified that the same receptor grid was used in all the models.

Comment 6: The rationale for the use of CALPUFF, ISC3, INPUFF, and VALLEY is not clearly explained. If all four models are used in the modeling protocol for full operation, it would be helpful to include a clearer discussion of the rationale for the use of each model.

EPA Response: The rationale for use of each of the air quality models is described in Section 2.1, General Methodology, of Volume III in the June 1996 Trial Burn Risk Assessment. The air quality modeling analysis consisted of a primary and supplemental analysis for both the normal trial burn emissions and upset conditions. The primary analysis for normal trial burn emissions used the ISC3 air quality dispersion model, and the primary analysis for the upset condition used the INPUFF model. The supplemental analysis for both normal emissions and upset conditions used the state of the science model CALMET/CALPUFF. The VALLEY model was not used in the analyses.

The ISC3 model was used to provide the primary estimate of all air concentration and deposition fluxes required for the exposure assessment. The CALMET/CALPUFF model was used to provide the concentration and deposition estimates using a more-comprehensive representation of the local wind field and to provide a complete set of concentration and deposition estimates under inversion/stagnation conditions. CALPUFF was used to provide a complete set of concentration and deposition values. As with the ISC3 estimates, these values were used to produce a second complete and independent set of risk estimates. The INPUFF model was used to estimate the ambient concentrations due to a relief valve release, since it could appropriately represent the varying emission rates and exit velocity of the relief valve release.

ATSDR Response: In the Emissions Modeling section, this comment (the sixth bullet) was deleted. When ATSDR staff read Section 2.1 of Volume II of the June 1996 Trial Burn Risk Assessment, they agreed that it provided a clear discussion of the rationale for the use of each model.

Comment 7: The sensitivity discussion in Volume I of the trial burn risk assessment, Section 8, compares ISC3 results with CALPUFF results, presumably at the same maximum concentration locations derived from ISC3 results. CALPUFF might yield significantly higher concentrations elsewhere. It is not clear whether each model was run independently to allow each one to project maximum impact locations. If one forces the non-steady-state models to predict concentrations at the same location as the ISC3 maximum location(s), the true maximum concentrations may be underestimated for both normal and upset conditions.

EPA Response: The ISC3 and CALPUFF models were run separately using the same receptor grid network. Maximum concentrations locations were determined independently for both models and compared independent of location.

ATSDR Response: In the Emissions Monitoring section, this comment (the seventh bullet) was deleted since EPA has clarified that both models were run independently.

COMMENT 8: The uncertainty and sensitivity analyses do not present quantitative assessment of the air quality modeling results. One approach to quantifying the uncertainty and sensitivity issues would be to exercise one of the models at a few locations, systematically varying the various input assumptions. This would yield an ensemble of model predictions that could help health scientists assess the values used in the risk assessment.

EPA Response: The Uncertainty Assessment does provide for a comparison of the two models used for the air quality analysis. The differences and variability in the two models was considered insignificant. The levels of conservatism embedded in the modeled assumptions was considered to overestimate risks (e.g. use of maximum emission rates and consideration of the duration of operation). Since the ISC3 and CALPUFF models were both run independently, and the differences in the respective results were determined to be insignificant, other changes in variables for subsequent model comparisons were deemed unnecessary.

ATSDR Response: Although we agree with EPA that comparing the two models was perhaps a way to evaluate the relative uncertainty of the models, we still think a more quantitative sensitivity analysis would be more convincing. When reviewing the comparison of ISC3 and CALMET/CALPUFF modeling results in Volume III, Section 5.2 of the 21 June 1996, risk assessment it is easy to agree that a 8% to 20% difference is not likely to affect the final risk numbers. However, when you see 40% to 132% differences, it is not easy to say these differences plus a factor of four difference for downwash and calm winds (Section 5.3) are insignificant when considered in an aggregate form.

Comment 9: Volume III of the risk assessment assumes that the particulate released during a TRV event would be primarily metals (not organics) and that they would be relatively large and thus would deposit on site. This assumption is contrary to the information in Table 2.4-2 of Volume I of the risk assessment. That table says all the metals except barium, beryllium, and chromium will be 100% volatilized during normal and upset conditions. Barium will be 50% volatilized, and beryllium and chromium will be 5% volatilized. It seems reasonable to assume that most of the metals will be in the vapor state when exiting the TRV and will be dispersed in the plume rather than being large particles that fall on site.

EPA Response: The air quality modeling for the TRV release utilized the emissions developed for the process upset conditions. These emission calculations are in Volume II, Section 3B.3.3 which presents the metal emission considering volatilization partition factors without emission controls. The emission used in the INPUFF modeling were simulated as vapor emissions since no particulate deposition was accounted for.

ATSDR Response: We have added references to our original comment to clarify which sections we think are in conflict. Since Volume III of the risk assessment still appears to be in conflict with other sections of the risk assessment, the comment has not been deleted. However, we do acknowledge that it appears from Volumes I and II that EPA did use more reasonable metal volatilization factors; contrary to the section in Volume III which discusses the uncertainties associated with the INPUFF model that they used for TRV release modeling. If EPA did modify the INPUFF model to assume the metals were vapor, then why doesn't Volume III, Section 5.3, state that instead of saying the INPUFF model assumed all the particulate dropped on site?

Comment 10: EPA assumed that during TRV events, the particulate emissions would be 10,000 times those occurring during normal operations. If this is equivalent to zero removal efficiency, the document should indicate that you are assuming no removal of particulate.

EPA Response: Section 3B.3 of Volume II describes the Emissions Survey process upset conditions. Metals (non-volatilized fraction) and particulate emissions were assumed to be uncontrolled (e.g., no removal of particulate).

ATSDR Response: This comment was deleted (the tenth bullet). EPA is correct, their assumption is clearly explained in Volume II, Section 3B.3.

Comment 11: ATSDR should review the draft proposal on how the full operation risk assessment will project TRV emissions. The proposal should provide references to support any assumptions.

EPA Response: The plan for the consideration TRV emissions in the full operation risk assessment is presented in the Work Plan for the full operation risk assessment, and is based upon the same approach used in the June 1996 analysis.

ATSDR Response: ATSDR was not provided with the draft proposal on how the TRV emissions would be projected or the "Work Plan for the full operation risk assessment". This comment was reworded to clarify that we are requesting references for (1) the assumption that after an initial puff of one minute duration, the emissions will decrease exponentially to zero within 25 minutes and (2) the assumption that during the first minute the DRE will decrease from 99.99% to 99%.


Conclusion 1: Automatic waste feed shut-offs (AWFSOs) were set on the key operating conditions, and the documents specified that the flame was to be maintained whenever it was safe to do so. The operating conditions and AWFSOs should ensure safe operation of the incinerator and prevent or minimize to the maximum extent possible exposure of the community.

EPA Response: No response required.

Conclusion 2: The continuous monitoring and recording of the key operating conditions and stack emissions will provide continuous documentation of the operation of the incinerator and the causes of any releases that may occur.

EPA Response: No response required.

Conclusion 3: The circumstances specified when the thermal relief valve (TRV) would be opened were only those that truly constituted emergency situations, when it would be more protective of public health to vent the hot gases through the TRV than to allow catastrophic equipment failure that would release the hot gases at ground level.

EPA Response: No response required.

Conclusion 4: Estimates of TRV emissions for full operation and modeling of those values would help investigators predict the public health impacts of upset conditions.

EPA Response: The full operation risk assessment currently being drafted will include an evaluation of upset conditions from TRV emissions. This evaluation will include the experience gained in the trial burn as well as existing data from other similar sources and will involve both an estimate of emissions and short term ambient dispersion modeling to appropriately estimate any potential public health impacts.

Conclusion 5: New modeling would be useful for evaluating the stack emissions measured during the trial burn. Modeling to date is not adequate to project the ground level concentrations in the communities around the Drake incinerator during full operation.

EPA Response: New modeling of full operation emissions is currently being conducted as part of the full burn risk assessment.


Recommendation 1: Conduct new modeling using 5 years of meteorological data and stack emissions rates measured during the trial burn and risk burn. Agency for Toxic Substances and Disease Registry (ATSDR) staff should review the draft modeling protocol before the modeling is conducted so that our input can be more pertinent and timely.

EPA Response: Modeling for the full operation risk assessment is underway pursuant to the work plan for this project. As discussed above, one (1) year of meteorological data (six-months of Lock Haven and six months of Williamsport) are used as the basis of the modeling for the body of the risk assessment. This approach maximizes the influence of local conditions in the meteorological modeling. A separate sensitivity analysis will be conducted to evaluate six months of on-site data combined with four and one-half years of Williamsport data. The resulting modeled ambient concentrations and depositions will be compared.

Measured stack emissions are being used as the basis for the calculation of emission rates during the full operation.

ATSDR Response: No changes have been made in this recommendation. The draft modeling protocol was not provided to ATSDR staff.

Recommendation 2: Reevaluate the assumptions used in projecting the emissions that will be released when operating conditions cause the thermal relief valve (TRV) to open. ATSDR should review and provide comments on the draft proposal on how TRV emissions will be projected in the full operation risk assessment.

EPA Response: The emissions from the potential TRV openings are being reevaluated as part of the full burn risk assessment. This reevaluation includes the experience gained in the trial burn along with information from other similar facilities. The approach and results will be included in the risk assessment report.

ATSDR Response: ATSDR was not provided with the draft proposal on how the TRV emissions would be projected. This comment was reworded to clarify that we are recommending that the following assumptions be reevaluated and references provided: (1) that after an initial puff of one minute duration, the emissions will decrease exponentially to zero within 25 minutes and, (2) that during the first minute the DRE will decrease from 99.99% to 99%.


ATSDR Supported Health Studies Related To Incinerators


Caldwell Systems, Inc. (CSI) operated a hazardous waste incinerator from 1977 to 1988, in Caldwell County, NC. The hazardous substances burned included: varnish, paint, glue, lacquer, toluene, xylene, and other solvents used by the regional furniture and pipeline industries, as well as waste torpedo fuel from the U.S. Navy. This incinerator operated without air pollution control equipment until 1987. Emissions from the site included smoke from the incinerator and fugitive emissions from the handling of hazardous wastes.

Original Study

    Study of Symptom and Disease Prevalence
    Caldwell Systems, Inc. Hazardous Waste Incinerator
    Caldwell County, North Carolina, September 1993

During July 1991, ATSDR conducted a cross-sectional symptom and disease prevalence study, collecting questionnaire data from 713 residents living within 1.5 miles of the incinerator (target area) and 588 residents of a comparison area. Subsequent analysis of this data revealed that residents of the target area were more likely than residents of the comparison area (after adjusting for potential confounders) to report recurrent wheezing or coughing, neurologic symptoms (dizziness and poor coordination), neurologic diseases, and irritative symptoms.

Follow-up Study

    Health Outcome Follow-up Study of Residents
    Living Near the Caldwell Systems, Inc. Site
    Caldwell County, North Carolina
    (a draft final report)

In a follow-up study conducted during August 1993, ATSDR administered questionnaires, pulmonary function tests (PFT), neurobehavioral tests, and tests of the immune system to participants selected from the original study (above). The follow-up study included 164 target area participants and 96 comparison area residents. One finding was that pulmonary function test results were worse among target area participants who reported respiratory symptoms at follow-up than among those who did not. A draft final report is available for review and is expected to be published early in FY98.



In 1988, the Arkansas Department of Pollution Control and Ecology (ADPC&E) contracted for the incineration of the drummed waste, using a $10.7 million combined trust fund and letter of credit obtained from Vertac during bankruptcy litigation. A contract for incineration of the drummed waste was signed in 1989 between ADPC&E and Vertac Site Contractors (VSC). VSC is a joint venture of MRK Incineration and Morrison-Knudsen Environmental Services.

In January 1992, the ADPC&E approved the VSC trial burn, and production scale incineration began. Because the drums were difficult to handle, incineration took longer than expected. There were extensive legal delays due to lawsuits. In May 1993, the trust fund money had been spent with about one half of the waste destroyed.

In 1990, the Arkansas Department of Health and the Agency for Toxic Substances and Disease Registry began planning the first of a series of studies addressing problems due to the presence of the site. The Historical Exposure Assessment Study and the Inhalation Exposure Assessment Study were initiated in 1991. The Health Outcome and the Reproductive Health Monitoring studies were initiated in 1993.

Reproductive Health Monitoring Study
Purposes: 1) To determine if there is a temporal association of birth prevalence rates to the Jacksonville Superfund sites, and 2) To determine if the birth prevalence rates differ between Jacksonville and the remainder of Pulaski County.

Results: Examination of adverse reproductive outcomes in Pulaski County over the period of 1980-1990, was performed to assess possible relationships to the past chemical manufacturing activities at the Vertac Superfund site in Jacksonville, Arkansas. Analyses included statistical comparisons of occurrences of fetal loss, birth defects, developmental disabilities and low birth weight between Jacksonville and the remainder of the county. Other studies included time trends and spatial analyses. The findings were:

- The increased fetal loss rates observed in the Jacksonville area in the early 1980s was not associated with spatial proximity to the Vertac Site.

- No indication of an excess in birth defects related to the Vertac site was observed.

- Weak associations were found for a few developmental problems, (such as seizures and neonatal seizures) and the Vertac site.

- Several clusters of low birth weight were noted in Pulaski County, including one to the southeast of the Vertac site.

- No indication of an association of fetal loss, birth defects or developmental disabilities with the passage of time was demonstrated.

The localized excess in low birth weight may account for the weak clusters of developmental disabilities. There is no direct evidence relating the low birth weight cluster to the southeast of the Vertac site to site activities. Further spatial studies of low birth weight and developmental disabilities are recommended, including evaluating possible relationships to body burdens and environmental data.

On going studies -

Historical Exposure Assessment
Purposes: 1) To determine if exposure to persistent chemicals at the site, including Dioxin and Dioxin-like compounds for more than 15 years, results in higher body burdens by conducting biomonitoring activities which include collection of medical history and blood samples; 2) To determine if exposure to non-persistent chemicals at the site including 2,4-D, 2,4-dichlorophenol, 2,4,5-T and 2,4,5-trichlorophenol for more than one year (as of 1991) results in higher body burdens by conducting biomonitoring activities which include collection of medical history and blood samples.

Incinerator Exposure Assessment
Purpose: To determine if remediation activities associated with the site clean-up, particularly handling and incineration of drummed wastes, results in increases in body burdens of site related chemicals by conducting pre- and post-incineration biomonitoring activities for estimating blood lipid concentrations and urine concentrations of site contaminants in nearby residents.

Health Outcome Study
Purpose: To test the hypothesis that "Group living for extended periods in a defined area near or adjacent to the site have a higher prevalence of acute or chronic illness, plausibly associated with exposure to persistent pollutants related to the site such as TCDD, than similar groups who live in an area far away from the site."

Effects of Dioxin-like Compounds on Glucose Regulation and Insulin Sensitivity (Diabetes Report)
Purposes: 1) To determine if there is a positive association between excess blood lipid levels of TCDD (and TEQ-TCDD) and an increased likelihood that elevated levels of insulin are necessary to control blood glucose concentrations within desirable physiological limits; and 2) To test if the association between excessive exposure to TCDD (TEQ-TCDD) and increased insulin concentrations follows a dose response.

Do Waste Incinerators Induce Adverse Respiratory Effects? An Air Quality and Epidemiological Study of Six Communities in North Carolina.

The University of North Carolina conducted a three-year epidemiological study of the prevalence and incidence of respiratory effects among residents of communities surrounding three types of waste incinerators (a biomedical incinerator, a municipal waste incinerator, and a liquid hazardous waste-burning industrial furnace), and three matched comparison communities.

Purposes: 1) To compare the prevalence of chronic respiratory symptoms, respiratory hypersensitivity, diminished lung function, upper respiratory tract inflammatory reactions, and upper and lower respiratory tract diseases in exposed and non-exposed communities, adjusting for the distribution of known risk factors for these conditions; 2) To select subcohorts of normal and of hypersensitive adults in these exposed and control communities and to obtain daily measurements of lung function and respiratory symptoms in these persons over a one month period, annually, for three years, with simultaneous daily measurements of air quality in each community; 3) To identify whether subgroups of the population are at higher risk of lung and respiratory disease from exposure to fugitive or stack emissions from incinerators.

Results from first year: differences in concentrations of particulate matter were detected among any of the three pairs of study communities. Average fine particulate (PM2.5) concentrations measured for 35 days varied across study communities from 16 to 32 ug/m3. Within the same community, daily concentrations of the fine particulate varied by as much as eightfold, from 10 to 80 ug/m3, and were nearly identical within each pair of communities. Direct measurements of air quality and estimates based on a chemical mass balance receptor model showed that incinerator emissions did not have a major or even a modest impact on routinely monitored air pollutants. A onetime baseline descriptive survey (n=6963) did not reveal consistent community differences in the prevalence of chronic or acute respiratory symptoms between incinerator and comparison communities, nor were differences seen in baseline lung function tests or in the average peak expiratory flow rate measured over a period of 35 days. Based on this analysis of the first year of our study, the investigators concluded that we have no evidence to reject the null hypothesis of no acute or chronic respiratory effects associated with residence in any of the three incinerator communities.

Results from subsequent years and the final report of this project are yet to be finalized.

1. Olie, K., Addink, R., and Schoonenboom, M. "Metals as Catalysts during the Formation and Decomposition of Chlorinated Dioxin and Furans in Incineration Processes". Journal of the Air & Waste Management Association 46:101-105 (February 1998).

Santoleri, J. J. "Dioxin Emissions - Effects of Chlorine, Time, Temperature Relationship at 300 oC". Proceedings of International Incineration Conference (1995).

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

A-Z Index

  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  27. #