Assessment of Cancer Incidence from the Louisiana Tumor Registry from 1988 - 1997
AMERICAN CREOSOTE WORKS, INCORPORATED (WINNFIELD)
WINNFIELD, WINN PARISH, LOUISIANA
In 1995, the Louisiana Department of Health and Hospitals, Office of Public Health,Section of Environmental Epidemiology (LDHH/OPH/SEET) prepared a public healthassessment for the American Creosote Works, Inc. At that time, it was determined thatthe American Creosote Works, Inc. site posed a public health hazard because of past, andpossibly present and future exposure to on-site soil, sediment, and surface water contaminated with polycyclic aromatic hydrocarbons (PAHs), pentachlorophenol (PCP),and dioxin. The exposures were estimated to be at levels that could exceed, individuallyor as a mixture, long-term health guidelines (1). As recommended in the 1995 PublicHealth Assessment, a health statistics review was conducted to evaluate whether thepopulation residing closest to the American Creosote National Priorities List (NPL) sitein Winn Parish, Louisiana, had elevated cancer incidence rates (1). The review consistedof two census tracts (the 1-mile proximity zone). The size of the population in the 1-mileproximity zone was approximately 6,800 persons. Cancer data (1988-1997) from theLouisiana Tumor Registry (LTR), a population based cancer incidence registry coveringthe entire state, was evaluated for this review.
A cancer review for the census tracts within 1-mile of the site compared to state ratescould not be completed due to the very low geocoding rate for cancer cases occurringnear the American Creosote Works, Inc. site. Many residents of Winn Parish have P.O.Box or Rural Route addresses; therefore, georeferenced coordinates could only beobtained for 257 of 582 cancer cases (44.2%) within the zip code enclosing the twocensus tracts of interest (71483).
Currently, the long-term phase of the Remedial Action for in-situ biological treatment ofcontaminated soil and the pumping and treatment of liquid contaminants is ongoing. Currently, on average, over 400,000 gallons of liquids (contaminated ground water andnon-aqueous phase liquids or NAPLs) are collected and treated per month, including over1,000 gallons of NAPL. The collected NAPLs are transported off site to a permittedfacility for incineration. Treated ground water is either reinjected into the ground as partof the in-situ biological treatment process or discharged to Creosote Branch Creek via apermitted outfall. The Environmental Protection Agency (EPA) continues to monitor theperformance of the remedy to assess its effectiveness in achieving the establishedremedial activities. EPA is addressing deficiencies identified during the Five-YearReview of the Remedial Action, including the presence of NAPL outside of the influenceof remedial systems and the clogging of extraction trench sumps. EPA is also evaluatingoptions for improving the performance efficiency of the operating remedial systems. This work should be completed in the next 1-2 years (2).
The 34.21-acre American Creosote Works, Inc. site is a former wood treatment facilitylocated less than 0.5 mile from the city of Winnfield, a rural, primarily low-income townwith a 1990 U.S. Census population of 6,138, in Louisiana (Attachment: Figure 1). Thesite is bordered by Creosote Branch (a small creek with banks 10 to 12 feet high) on thenorth and east, Front Street on the west, and a residential access road on the south andeast. Since 1901, the site was utilized for various operations, and was finally obtained bythe Stallworth Timber Company in 1979. In 1985, the timber company abandoned thefacility.
The facility pressure treated telephone poles, railroad crossties, and lumber with creosoteand PCP. Untreated timber was debarked and staged on the south side of the site. Thetimber was then railed into pressure vessels for treatment, and to layout yards on thenorth side of the site for drying and shipment.
Hazardous substances, including various PAHs, dioxins, benzene, and PCP were found insite soils, liquids, and sludges in the plant area, the sludge lagoon , the site drainagecourses, and Creosote Branch. The shallow aquifer (5 - 30 feet deep) underlying the sitewas found to be contaminated with PAHs, benzene and phenols. Monitoring wellsscreened at 5 to 20 feet were reported to contain 1-foot of floating creosote and severalinches of floating oils.
In addition, two drainage ditches originated on the site near the plant area, and a thirdcrossed the site from south to north. From west to east, depths of the ditches were 1-2feet, 3-5 feet, and 8-12 feet. Pools of black, tar-like material could be observed in thebanks of the drainage ditches. It appears that rainfall runoff washed this material fromthe ditches into Creosote Branch. Creosote Branch continues for about 2 miles to theconfluence with Port de Luce Creek, which flows for another 3 miles to the southeast,then joins Cedar Creek before emptying into the Dugemona River. This river is one ofthe larger waterways in the Winnfield area and ultimately drains into the Little River inthe southeastern section of Winn Parish. The State of Louisiana Stream ControlCommission began investigations at the American Creosote Works, Inc. facility in 1966,citing high levels of phenols and a high biological oxygen demand (BOD) in plantdischarges, and phenol and creosote releases into Creosote Branch (1).
During the EPA Removal Action in 1989, the American Creosote Works, Inc. siteconsisted of 15 large storage tanks, three large and six small pressure treating units, threeoffice maintenance sheds, a tool and dye shop, a gasoline pump with undergroundstorage tanks, five monitoring wells, a small chemical laboratory west of the plant areanear Front Street and the site access road, a sludge pit, a lagoon that has been backfilledwith wood chips, and a pond on the northern portion of the site. Historically, according toLouisiana Department of Environment Quality (LDEQ) reports, the swampy area at thesite had been covered by a few inches to about 1 foot of tar-like material.
On May 16, 1996, during remediation, SEET staff visited the American Creosote facility. At the front gate of the site on Front Street, the incinerator was being assembled. Acrossthe street from the site, the embankments of Creosote Branch were free of creosotematerial, debris, and other garbage. At that time, the water levels were a few inches high,however, it appeared at times that the Branch appeared to reach high levels (4 - 6 feet)with fast moving water because the vegetation around the embankments was pushedback. The site appeared to be clean and had been bulldozed and all trash and physicalstructures had been removed. Two large pits with linings on the bottom were visiblefrom the fence line. The pits were empty at that time, but would hold the residual waterremaining after bioremediation and carbon filtration. Other site features were drainageditches on site and an air sampling station on the fence line parallel to Watts Street.
In February 1998, the incineration phase was completed. Approximately 7000 cubicyards of soil were excavated and due to low levels of contamination, were consolidatedinto the process area where it underwent in-situ biodegradation. The water treatmentplant for the in-situ bio-treatment system was completed in February 1997 and over 8million gallons of contaminated groundwater including 140 barrels of pure creosote wereinitially treated. The plant will continue to operate for the implementation of the long-term in-situ bioremediation. The incinerator has been decommissioned and transportedoff-site. The completion of the in-situ bioremediation system has effectively eliminateddischarges to Creosote Branch, allowing the stream to recover to natural conditions (2).
Currently, over 540,000 gallons of fluid are recovered and treated on site per month, withnearly half of that volume re-injected into the ground as part of the in-situ bioremediationsystem. The remaining treated water is discharged to Creosote Branch. Over 1,500gallons of creosote and oil are currently recovered from this treatment process per month. The creosote and oil are sent off site for incineration. A total of 101,540 gallons ofcreosote and oil have been collected from the site to date.
The LTR was used to ascertain cancer cases. The LTR, operated by the Louisiana StateUniversity Health Sciences Center, is a population-based cancer registry covering theentire state of Louisiana. The registry has been in operation in the New Orleansmetropolitan area since 1974, in South Louisiana since 1983 and in the rest of the statesince 1988. By law, every health care provider is required to report newly diagnosedcancers.
The registry information available for each newly diagnosed cancer case is limited and itis documented from the patient's medical record. Information collected includesdemographic and medical data on each individual cancer patient such as name, address attime of diagnosis, census tract code, primary cancer site, histology type, date ofdiagnosis, age at diagnosis, birth date, race, sex, and registry identification number. Toensure that reported data are complete and accurate, Louisiana Tumor Registry staffmembers perform case-finding and other quality control checks at these institutions.
The period of time selected for evaluation of cancer incidence data was 1988-1997,which was the most recent data available for this part of the state at the time of thisanalysis. Cancer incidence was chosen for this review because cancer death rates areaffected by multiple factors: how advanced the cancer was at the time of diagnosis,access to health care, and other factors not related to exposure (3).
A geographical information system (GIS) was utilized to define and estimate populationsliving near the American Creosote Works, Inc. site and to assist in the identification ofcancer cases that occurred in residents near the site during the years 1988 to 1997. Although, the site operated from 1901 to 1985, the LTR data was not available at thattime.
The use of GIS provides a method for analyzing cancer in geographic areas not definedby town boundaries and to look at smaller geographic areas. Specifically for this review,SEET focused on the census tract (approximately 1000 to 4000 persons) and censusblock groups (approximately 600 to 650 persons) as the geographic areas of interest.Census tracts and block groups were used instead of census blocks (approximately 80 to100 persons) because blocks do not provide the age, race, and sex population data neededto analyze cancer incidence data. Street Atlas© software was used to obtain latitude andlongitude coordinates for the cancer cases with valid street address information. Thesecases were plotted using MapInfo© software on a base map of Winn Parish census tractsto determine which geocoded cases occur within the census tracts within 1 mile of theAmerican Creosote Works, Inc. site. Property maps of the American Creosote, Inc. sitein Winn Parish were obtained from the LDEQ. The perimeter of the site was digitized inthe Universal Transverse Mercator (UTM) coordinate system using Intergraph/MGE GISsoftware system. Topologically Integrated Geographic Encoding Referencing (TIGER)files containing boundaries for census tracts and blocks for the parish were obtained. Thedigital files were cleaned and their coordinate systems were standardized to the UTMsystem. The block files were further processed through overlaying with census tract filesso that a unique identifier for each census block was included.
Next, in order to retrieve the census blocks that intersect with the 1-mile proximity zoneof the site, the digitized NPL boundary file and census block file were overlaid usingIntergraph/ MGA software and an overlay file (a topo file in Intergraph terminology) wascreated. The 1-mile proximity criterion was then imposed as a search criterion in thequery set. Then, the query searched the overlay file using the criterion and returned withthe census blocks that met the criterion. The census block groups identified in theAmerican Creosote 1-mile proximity zone were in two census tracts, 9603 and 9604.
Winn Parish is a predominantly rural area with many residents listing addressinformation as Post Office Boxes or Rural Routes. The LDHH/OPH/SEET currentlydoes not have a means of obtaining accurate latitude-longitude coordinates for suchaddresses. Out of 582 cancer cases found within the zip code (71483) that encompassesthe two census tracts in the 1-mile proximity zone (9603 & 9604), geocoding wassuccessfully performed for 257 cases. Because of this very low geocoding rate (44.2%),SEET and the Agency for Toxic Substances and Disease Registry (ATSDR) agree thatany standard incidence ratio (SIR) calculations performed on the subset with matchinglatitude and longitude coordinates will be unreliable and are likely to be anunderestimation of actual cancer incidence in the 1-mile proximity zone. Therefore, thegoal of this report could not be met and only demographic data are presented.
In order to characterize the population living within the census tracts within 1-mile of thesite, 1990 census data were evaluated as shown in Table 1. The racial composition ofresidents living within the census tracts within 1-mile of the site differs from the state inthat 45.7% of the residents are black compared to 30.8% in the state and 53.3% of theresidents are white compared to 67.3% in the state. The proportion of persons livingbelow poverty is higher within the census tracts within 1-mile of the site (36.4%) than thestate (23.6%) and the proportion of families living below the poverty level is higherwithin the census tracts within 1-mile of the site (29.7%) than the state (19.4%). Incomeindicators for the population within the census tracts within 1 mile of the site are lowerthan the state. There are also older homes within the census tracts within 1-mile of thesite.
|Demographic Characteristic||Louisiana (%)||American Creosote (%)*|
|Total Population||4,219,973 (100)||6,767 (100)|
|White||2,839,138 (67.3)||3,605 (53.3)|
|Black||1,299,281 (30.8)||3,090 (45.7)|
|Other||81,554 (1.9)||72 (1.0)|
|Female||2,188,587 (51.9)||3,652 (54.0)|
|Male||2,031,386 (48.1)||3,115 (46.0)|
|No. of Families||1,098,374||1,715|
|No. of Households||1,498,371||2,389|
|Median Age (years)||31.0||32.3|
|Annual Income (dollars)|
|Year residence constructed (median)||1969||1962|
|* The census tracts within 1 mile of the site (9603 and 9604).|
One of the primary concerns expressed by communities is living near a hazardous wastesite and the effect it has on their health. Latitude and longitude coordinates confirmingcase location within the census tracts within 1-mile of the site were found for 257 of the582 cancer cases (44.2%) within the zip code 71483. Due to the low geocoding rates acancer review could not be completed. Residents of the 1-mile proximity zone weremore likely to be black and had higher percentages of persons and families below thepoverty line than the State.
The investigators encountered difficulties in geocoding a large proportion of the cancercases occurring within Winn Parish, 1988-1997, due to addresses listed as Post OfficeBoxes and Rural Routes. At the present time LDHH/OPH/SEET does not possesstechnology, which would enable a more accurate geocoding system for non-streetnumber addresses. Analysis of the 1-mile proximity zone compared to Louisiana couldnot be completed due to the small proportion of cancer cases with geocodable addressinformation (257 of 582, or 44.2%).
The objective of this investigation was to determine whether elevated cancer rates ofcancer exist in the community living around the former American Creosote Works, Inc.wood-treating facility as compared to cancer incidence in Winn Parish and the state ofLouisiana. The main findings from this investigation are as follows:
- Because of the very low geocoding rate (44.2%) a cancer review could not becompleted.
- SEET and ATSDR agree that any SIR calculations performed on the subset withlatitude and longitude coordinates will be unreliable and are likely to be anunderestimate of actual cancer incidence in the 1-mile proximity zone.
Community Health Concerns have been addressed in the Preliminary Public HealthAssessment for American Creosote Works, Inc.(1).
- LOPH will place this public health consultation in the local repository for theAmerican Creosote site. LOPH will review relevant data as it is provided by EPAduring the 5 year plan for the site and complete health evaluations on the data andreport any relevant public health findings to the community. After EPA's 5 yearplan is complete and if community interest is apparent, LOPH will review andevaluate additional data for health outcomes.
- Louisiana Office of Public Health (OPH), Preliminary Public Health Assessmentfor American Creosote Works, Incorporated, March 9, 1995.
- U.S. Environmental Protection Agency (EPA), American Creosote Works, Inc.,February 1, 1999.
- National Institutes of Health, National Cancer Institute, Cancer Rates and Risks. 4th Edition, 1996.
Louisiana Department of Health and Hospitals
Office of Public Health
Section of Environmental Epidemiology and Toxicology
Telephone Number: (504) 568-8537 or toll-free (888) 293-7020
Zoe' M. Wilson, MPH
Environmental Health Scientist Coordinator
ATSDR Senior Regional Representative
Regional Operations, Region VI
ATSDR Technical Project Officer
Tammie McRae, MS
Environmental Health Scientist
This American Creosote, Inc. site, assessment of cancer incidence, health consultationwas prepared by the Louisiana Department of Health and Hospitals under a cooperativeagreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is inaccordance with approved methodology and procedures existing at the time this healthconsultation began.
Tammie McRae, MS
Technical Project Officer, DHAC
The Division of Health Assessment and Consultation, ATSDR, has reviewed this publichealth consultation and occurs with the findings.
Lisa C. Hayes
for Roberta Erlwein
Cooperative Agreement Team Leader, DHAC, ATSDR