Responding to Chemical Emergencies: Rockton, IL, Case Study

Three people standing and smiling together, two with orange vests on holding papers.

ATSDR Region 5 Director Mark Johnson and CDC Epidemic Intelligence Service Officers Jasmine Nakayama and Krishna Surasi contacting residents distributing flyers in the neighborhood adjacent to the fire. Photo Credit: Mark Johnson.

Building professional relationships amongst agencies before an emergency event happens is key to establishing how well a response will go. ATSDR participates in interagency planning at the national and regional level and supports interagency planning at the state and local level to develop these relationships in advance.”


— Rich Nickle, MPH, ATSDR Emergency Management Hazardous Materials team lead

ATSDR, Environmental Protection Agency (EPA), and others collaborated with the Illinois Department of Public Health (IDPH) to assess health effects and support communities after a chemical explosion and large fire occurred at one of the largest lubricant manufacturing facilities in the United States.

When a natural or technological disaster or emergency strikes, ATSDR Emergency Management (EM) and CDC’s National Center for Environmental Health (NCEH) work as a central coordination point for responding. By triaging and coordinating NCEH/ATSDR’s emergency response assets and unique expertise, EM helps federal, state, and local entities respond to environmental health emergencies. These entities also collaborate to address public health consequences of terrorist events and hazardous substance releases.

Under the coordination of EM, Office of Innovation and Analytics (OIA), Office of Community Health Hazard Assessment (OCHHA), and Office of Capacity Development and Applied Prevention Science (OCDAPS) also support emergency responses. OIA offers Assessment of Chemical Exposure (ACE) resources to perform rapid epidemiologic assessments. OIA’s Geospatial Research, Analysis, and Services Program (GRASP) can help identify affected or at-risk areas, and OIA’s Toxicological Section offers substance-specific toxicological expertise during an incident. OCHHA’s 10 regional offices, located within the Environmental Protection Agency’s (EPA) regional offices, provide unique technical and field experience from their assigned regions. ATSDR’s Partnership to Promote Localized Efforts to Reduce Environmental Exposure (APPLETREE) recipients provide technical assistance and engage affected communities about potential exposures and ways to protect their health. Pediatric Environmental Health Specialty Units, or PEHSUs, supported by ATSDR’s Office of Capacity Development and Applied Prevention Science (OCDAPS), provide information to affected communities on how to protect their health and help children cope during and after disasters. PEHSUs also educate healthcare professionals caring for the affected communities.

On June 14, 2021, a chemical explosion resulted in a large fire at one of the largest lubricant manufacturing facilities in the United States, in Rockton, Illinois, near the Wisconsin border. Smoke from the fire lasted several days, affecting communities miles away in each state.

A city dubbed as a “true Midwestern village,” Rockton is home to nearly 8,000 residents, according to the 2020 Census. As the fire raged on in mid-June, an evacuation order was issued by the local fire department for residents and businesses within a 1-mile radius of the explosion site, to reduce exposure to hazardous materials. People within a second zone, from 1 to 2 miles out, were advised to stay inside their homes and keep their windows and doors closed. All people within 3 miles of the manufacturing facility were instructed to wear masks.

As the plume spread, health officials were concerned that volatile and semi-volatile organic compounds, asbestos, lead, cyanides, and acids could be present in the fire debris, due to the building age and chemicals used in its day-to-day operations. These hazards had the potential to cause cancer, heart and respiratory damage, and reproductive and developmental health effects. Action was critical to reduce the potential for harm. Furthermore, as a high energy fire, it was imperative that debris fields be mapped out to identify where the debris had landed and who was at most risk of exposure.

Supporting the Immediate Crisis Response

Given the urgency, personnel from multiple federal, state, and local agencies and organizations responded to help Rockton. EM’s expertise in chemical emergencies helped identify potential health effects in the immediate vicinity of the facility, such as respiratory irritation and cardiovascular effects in sensitive populations. After identifying harmful short-term exposures in the community, ATSDR provided affected residents with resources for dealing with deposited dust and associated odors and handling stress after an environmental contamination.

EPA’s Region 5 office requested assistance from ATSDR in determining next steps for screening, sampling, evaluation, and education. ATSDR supported the immediate crisis response over a 6-week span by

An air monitor with particles in the air towards the left.

Providing screening values for real-time air monitors of all recommended chemicals of concern.

A computer monitor showing a line graph and a magnifying glass at the bottom.

Leading the collaboration, alongside public health authorities, to review the environmental data collected by EPA and Illinois to evaluate potential contamination of air, surface water, sediment, and groundwater in the community.

An air filter showing particles and three arrows demonstrating air flow.

Recommending air sampling based on aerial images of the fire and information about chemical processes within the building.

Two sheets of paper, one having lines and a checkmark signifying factsheets.

Developing factsheets with Illinois’s state and local health departments to educate the community on how to protect themselves after returning home from the fire.

EM coordinated with ATSDR’s Region 5 office, the APPLETREE grantee at the Illinois Department of Public Health (IDPH), the Region 5 Pediatric Environmental Health Specialty Unit, NCEH/ATSDR’s Office of Communication, and OIA’s surveillance team to support this work.

Listening and Responding to the Affected Communities

Once ATSDR Emergency Management, Illinois Department of Public Health (IDPH), and Winnebago County Health Department collected and analyzed the environmental data, it was time to go to the people who mattered most—the Rockton residents, business owners, and first responders.

In early July, the county health director and state epidemiologist asked ATSDR to conduct an Assessment of Chemical Exposures (ACE) investigation. ATSDR’s OIA, along with state and county health officials and ATSDR regional staff, conducted a survey of residents in the 11 ZIP code areas identified by syndromic surveillance and plume modeling as the most affected, and responders. The goal was to assess possible exposures, health effects, and current needs due to the explosion and resulting smoke and debris.

Because of COVID-19 concerns, OIA did not perform its usual in-person surveys. They were fortunate to be able to use the county health department’s patient engagement system, which had been used to register people for COVID vaccines, to reach more than 40,000 people in the 11 affected ZIP code areas with an online survey. The survey link was also shared through press releases, social media posts, and the county health department’s website.

GRASP was consulted to prepare maps of survey participation, which identified an area of low participation near the location of the fire. ATSDR staff decided to visit this community to promote the survey and learned its residents were mostly older persons with limited internet access. Residents expressed concerns to the staff about longstanding groundwater contamination from an existing Superfund site located on the same site as the manufacturing facility. This conversation led to a request for more thorough water testing for the Superfund area, which was conducted by the Winnebago County Health Department.

This first attempt at completing the ACE survey online was very successful, with a total of 2,030 unique survey respondents within 2 weeks’ time. Of the survey respondents, 45.1% reported one or more new or worsened symptoms since the fire, typically related to their ears, nose, and throat (69.7%); nervous system (52.2%); and eyes (41.8%). Four respondents reported being in the hospital after the fire.

Working with the CDC One Health office, OIA was able to develop a follow-up survey about pet and livestock health to people who said they had them in the first survey. GIS mapping and analysis of the responses was used to show where the smoke plume and fire debris traveled, document health symptoms, and identify gaps in first responder personal protection equipment.

OIA produced an initial summary and recommendations presentation for the health departments that was used by the county health department to create a presentation to the community about the reported exposures and health effects and guidance for about how to protect themselves and reduce exposure. The results were also made more broadly available in the Morbidity and Mortality Weekly Report (MMWR) Notes from the Field article and a more detailed analysis will be published in the future.

This case study demonstrates the level of quick response and collaboration needed for successful emergency response. By prioritizing emergency preparedness and activating established interpersonal relationships, response teams were able to form quickly to protect and empower community members and families in Rockton after this disaster.