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On February 9, 2003, a Canadian National Railway/Illinois Central Railroad Company (CNIC) northbound train derailed in Tamaroa, Perry County, Illinois. Several of the derailed cars contained vinyl chloride, hydrochloric acid, methanol, or formaldehyde. Damage to some of the cars allowed chemicals to be released into the surrounding environment. Some of the cars also caught fire. In response, residents within a 3-mile radius of the derailment were evacuated.

This report summarizes the events that occurred during the emergency response to the derailment and subsequent immediate removal of contamination associated with the chemical release. The Illinois Department of Public Health (IDPH) reviewed available information and data to determine whether conditions associated with the train derailment posed a public health hazard.


IDPH staff were notified about 10:00 AM on February 9, 2003, that 21 cars of a CNIC northbound train derailed in Tamaroa, Illinois. Several of the derailed cars contained hydrochloric acid, vinyl chloride, methanol, or formaldehyde. The derailment damaged some of the cars, causing chemicals to be released into the surrounding environment. Emergency responders were informed of the potential health effects of these chemicals. Potential acute health effects included the following:

  • hydrochloric acid–eyes, skin, and respiratory system irritation [1]
  • vinyl chloride–eyes, mucous membrane, and respiratory system irritation; breathing high levels can cause dizziness, sleepiness, and a tingling sensation [2]
  • methanol–blurred vision, headaches, dizziness, and nausea [3]
  • formaldehyde–eyes, skin, and respiratory system irritation [4]

Some of the damaged rail cars caught fire, creating an explosion hazard. Approximately 1,000 Tamaroa residents living within a 3-mile radius of the derailment were evacuated.

Tamaroa is a small, rural community on U.S. Route 51 in Perry County, Illinois. The CNIC railway runs north and south through the center of the community between Chestnut and Oak Street. The train derailed on a stretch of line between East 1st South Street and East 3rd South Street (Attachment 1). Emergency response crews secured the area and began containing the release of chemicals. Emergency response activities included the following:

  1. establishment of a secured zone around the derailment;
  2. establishment of an air monitoring network around the site and town to include on-site and perimeter stations to monitor vapors resulting from the derailment;
  3. collection and transfer of leaking chemicals from derailed tank cars into stable containers away from the derailment site;
  4. excavation of grossly impacted soil and rock; and
  5. clean-up and removal of railcars [5].

By approximately 5:00 PM on February 9, site perimeter and on-site air monitoring stations were recording ambient air measurements for vinyl chloride and the other chemicals spilled during the derailment. The levels were closely monitored for on-site worker protection. On-site workers also were monitored for vinyl chloride exposure by testing urine samples following completion of their shift.

Most of the chemicals were contained near the railroad tracks in the general area of the train derailment. Hydrochloric acid reportedly entered an east-west drainage ditch and flowed off the site. Approximately 2,000 feet of soil contaminated with hydrochloric acid was excavated from the drainage ditch. Surface water from affected ditches also was removed and held in storage containers for proper disposal. Areas of standing water created from significant rainfall were monitored to ensure levels of chemicals discharging from the site were below Illinois Environmental Protection Agency (Illinois EPA) criteria [5]. Illinois EPA monitored all emergency clean-up activities.

On February 11, at 1:00 PM, residents outside a 1-mile evacuation zone were allowed to return to their homes. Residents who lived within the 1-mile evacuation zone were not allowed to return to their homes until after clean-up crews stabilized a leaking vinyl chloride tanker. The 1-mile zone included all the Tamaroa residents within the city limits (approximately 800 residents) (Attachment 2). Air monitoring identified measurable vinyl chloride levels near the leaking tank, but perimeter monitoring did not identify any vinyl chloride vapors in populated areas.

By 6:00 PM on February 14, conditions at the derailment site were stabilized and the 1-mile evacuation zone was rescinded. A temporary fence was placed around the contaminated zone to prohibit trespassers from walking through the area. Clean-up crews remained on the site removing derailed cars and contaminated soil and replacing damaged rail.

IDPH staff assisted in the emergency response by monitoring air inside homes, businesses, and the local elementary school to ensure they had not been affected by chemicals from the derailment. Based on the results of the air monitoring, all residents were allowed to return to their homes on February 14. Since then, additional air sampling was completed in approximately 130 homes and eight local businesses, with no contamination associated with the derailment found [6]. Soils in residential yards were screened for site-related chemicals with direct reading instrumentation and field lab methodology. Site-related chemicals were not detected in residential yards using these methods of screening.

At approximately 8:30 AM on February 20, a valve on a tank containing hydrochloric acid failed, releasing a cloud of hydrochloric acid into the outdoor air. The visible cloud of hydrochloric acid traveled southwest from the site. Crews with air monitoring equipment tracked and followed the cloud, but measurable levels of hydrochloric acid were never detected and the cloud rapidly dissipated. The Tamaroa school is northwest of the site and was not in the path of the hydrochloric acid cloud. As a precaution, however, air monitoring was conducted outside of the school following the release. No measurable levels were detected, but the school administration chose to move the students to the community center and close the school for the remainder of the day. Air monitoring conducted inside the school building found no contamination.

By March 29, 2003, the emergency clean-up was completed. The chemicals had been removed from the site, along with contaminated soil, surface water, and debris. Throughout the clean-up and soil removal, ambient air sampling was conducted for on-site worker safety and to ensure chemicals were not affecting off-site areas. Following the emergency clean-up, the railroad agreed to conduct further site assessment, including additional soil sampling and installation of groundwater monitoring wells.

In July 2003, IDPH assisted with residential air sampling in Tamaroa at a select number of homes near the derailment site and the community school. The purpose of the additional sampling was to determine the levels of vinyl chloride, if any, inside the structures. Two homes adjacent to the derailment site and the Tamaroa Grade School were sampled, as were two background locations in Mt. Vernon, Illinois. Laboratory analysis of the air samples, with a detection level of 5 parts per billion (ppb), did not detect vinyl chloride at any of the sampling locations. IDPH reviewed the results and discussed the findings with residents of the homes sampled.


Four private wells within 2 to 5 blocks of the derailment site were identified and sampled. Most of the wells have a shallow, brick-lined construction and are no longer used for drinking water. A municipal water supply, originating from Rend Lake (approximately 15 miles east of Tamaroa), serves residents of Tamaroa and much of the surrounding rural community. Since the derailment, monthly samples have been collected from four private wells and several locations along Tamaroa's municipal water lines to ensure site-related chemicals did not contaminate these sources. The analytical results obtained from these samples show that the spilled products have not affected these water sources. No site-related chemicals were identified at levels greater than U. S. Environmental Protection Agency health guidelines.


Chemicals of Interest

IDPH compared the results of each sample collected with the appropriate comparison values to select chemicals for further evaluation for exposure and possible carcinogenic and non-carcinogenic health effects. Chemicals found at levels greater than comparison values or those for which no comparison value exists were selected for further evaluation.

Although none of the chemicals exceeded current comparison values in the samples taken, residents in the community were concerned about exposure to the chemicals that were released during the derailment. The chemicals of interest include methanol, vinyl chloride, hydrochloric acid, and formaldehyde.

Exposure Evaluation

The potential for persons to experience adverse health effects from exposure to a chemical depends on various factors:

  • how much of the chemical a person contacts,
  • how long the exposure lasts,
  • the age and health condition of the person when exposure occurs.


Within hours of the derailment, the entire community of Tamaroa, including the surrounding area up to 3 miles, was evacuated. This action greatly reduced exposure for the surrounding community to the chemicals released from the train cars. The accident also occurred during the winter when most windows and doors would not be open and people would typically spend less time outdoors. The cold temperatures would also reduce the amount of chemicals that might volatilize into the air. This further reduced exposure to chemical vapors that may have been released into the outdoor air.

Residents were not allowed to return to their homes until the situation at the derailment site was stabilized. After the site was stabilized, site perimeter air monitoring stations did not identify site-related chemicals affecting populated areas. Air sampling conducted inside several Tamaroa homes, local businesses, and the community school did not identify any chemicals associated with the derailment. Screening of residential soils did not identify site-related chemicals. Residue wipe samples (pH tests) collected on the exterior surfaces of homes and buildings and several interior surfaces did not identify the presence of acidic residue. The pH of fish tanks, swimming pools, and hot tubs was tested at the request of homeowners and found to be within normal pH ranges.

Tamaroa residences are connected to a municipal water supply that has not been affected by the chemicals spilled at the derailment site. Illinois EPA has sampled the municipal water supply at several locations in the community and has not found any site-related chemicals. Based on monthly sampling results, private groundwater wells also have not been affected by chemicals from the derailment.


Emergency response workers–trained to respond to hazardous materials releases and properly equipped with protective gear–remained on the site to stabilize the tanks and prevent the release of chemicals. Proper use of personal protective equipment should have reduced worker exposure. On-site air monitoring was conducted at all times to ensure workers were wearing the proper level of protection. Biological monitoring for vinyl chloride exposure also was conducted through the collection and testing of urine samples from on-site workers.


IDPH recognizes that children are especially sensitive to some chemicals because their developing systems are more vulnerable. Children also breathe more air than adults do on a per weight basis. For that reason, IDPH considered children when evaluating exposures to chemicals associated with the train derailment. Children are the most sensitive population considered in this health consultation. No adverse health effects would be expected for children in the Tamaroa area as a result of this incident.


IDPH concludes that under current conditions, exposures to chemicals associated with the train derailment are not at levels expected to cause adverse heath effects. This site poses no apparent public health hazard. Immediately following the train derailment, before evacuation could begin, exposure to chemical vapors may have resulted in respiratory, eye, or skin irritation. Because of the rapid evacuation, however, any exposure would have been brief. No detectable levels of chemicals associated with the derailment were found inside homes. Perimeter air monitoring around the site also showed that site-related chemicals from the area of clean-up were not affecting residential areas. Release of chemicals from the damaged railcars was rapidly controlled and remediated, minimizing contamination to the surrounding area. Illinois EPA monitored all clean-up activities associated with the train derailment site.


IDPH has reviewed the private well water sampling results and provided written responses to homeowners regarding those results. IDPH will continue to review and respond to the results as the sampling continues and will continue to answer any future community questions related to health concerns associated with the train derailment.


Lynn M. Stone
Environmental Health Specialist
Illinois Department of Public Health


  1. Agency for Toxic Substances and Disease Registry. ToxFAQs for hydrogen chloride. Atlanta: US Department of Health and Human Services. 2002 Apr.

  2. Agency for Toxic Substances and Disease Registry. Toxicological profile for vinyl chloride. Atlanta: US Department of Health and Human Services. 1997 Sep.

  3. USEPA Chemicals in the Environment: Methanol. Available at: Accessed November 7, 2003.

  4. Agency for Toxic Substances and Disease Registry. Toxicological profile for formaldehyde. Atlanta: US Department of Health and Human Resources. 1999 Jul.

  5. Shaw Environmental & Infrastructure, Inc. Emergency action summary report, Tamaroa derailment site, Illinois Central Railroad Company, Tamaroa, Illinois. Baton Rouge: The Shaw Group, Inc. April 28, 2003.

  6. Center for Toxicology and Environmental Health, LLC. The interim emergency action report, Illinois Central Railroad, Tamaroa derailment site, Tamaroa, Illinois. Little Rock, Arkansas: Center for Toxicology and Environmental Health, LLC. April 24, 2003.


The Illinois Department of Public Health prepared this Tamaroa Train Derailment health consultation under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the health consultation was begun.

W. Allen Robison
Technical Project Officer
Superfund Site Assessment Branch (SAAB)
Division of Health Assessment and Consultation (DAC)

The Division of Health Assessment and Consultation, ATSDR, has reviewed this health consultation and concurs with its findings.

Lisa C. Hayes
for Roberta Erlwein
Chief, State Programs Section


Tamaroa, Illinois


Tamaroa 3 and 1 Mile Evacuation Area

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