Local Public Health's Role in Large-Scale Chemical Incidents

by Rachel Schulman

Public health departments play, or have the ability to play, a key role in large-scale incidents caused by hazardous materials. By clearly defining their roles and collaborating with local partners, health departments have the ability to help emergency planners and responders prevent, mitigate, plan for, and respond to chemical hazards and incidents.

Large-scale chemical incidents – such as the West, Texas, fertilizer plant explosion in 2013, the Graniteville, South Carolina, train crash chlorine release in 2005, and the Tokyo, Japan, sarin gas release in 1995 – pose unique threats to human health that warrant specialized planning by first responders. Chemical incidents often unfold quickly, and serious exposure symptoms develop equally fast. Although these circumstances necessitate quick action by first responders, the information that responders need to make decisions may not be readily available. Chemical agents may take time toentify and, in the case of a surreptitious release, it may not be immediately evident that a chemical event has occurred. Responders may find themselves in the position of making high-consequence decisions that are not fully informed.

Defining the Roles of Local Health Departments In collaboration with the Department of Homeland Security Office of Health Affairs, the National Association of County and City Health Officials (NACCHO) sought to determine how local health departments (LHDs) could best contribute to a large-scale chemical event response. After a research review, NACCHO conducted a multidisciplinary focus group of 33 local, state, federal, and nonprofit agency representatives in the National Capital Region. Key research objectives were to understand the roles that LHDs currently play in response to a large-scale chemical incident, to pinpoint challenges that limit the LHD role in these responses, and toentify additional roles for LHDs that capitalize on their unique capabilities and resources.

The overwhelming message of the National Capital Region focus group was that the role of LHDs in a chemical response is not well defined. Though LHDs have responsibility for protecting human health in all hazards, the role of LHDs is often perceived to be limited to disease prevention and control. The perception of chemical incidents as hazardous material (hazmat) events, and not public health events, may result in LHDs being left out of the loop, even after the incident transitions to a mass casualty or mass fatality event.

As long as hazmat responders are unaware of LHDs’ chemical event response capabilities, LHDs likely will find that they continue to be left out of chemical event planning and response, to the detriment of communities and their response partners. To facilitate conversations on this important topic, NACCHO’s research highlighted the many roles that LHDs can play in a chemical incident. Even though all localities operate differently, the roles described below should be considered when planning with public health partners.

Prevention & Mitigation of Chemical Incidents LHDs offer unique perspectives on chemical threats to the community through their intimate knowledge of community vulnerabilities. LHDs regularly conduct surveillance activities – for example, community health assessments and geographic information system mapping of at-risk populations – that inform them of the locations and needs of different community groups. This knowledge can be used to inform decisions about local-level chemical storage, use, and disposal practices, and to assess risks to nearby populations.

By participating in the inspection and regulation of chemical facilities, LHDs gain a better understanding of the nature of the greatest chemical threat facing jurisdictions. This understanding allows LHDs to better prepare the community for potential health and environmental impacts. Precedents exist for the involvement of LHDs in the inspection and regulation of chemical facilities. For example, the Town of Acton, Massachusetts, enacted local bylaws that provide the health department with the authority to permit and inspect commercial facilities’ manufacturing, use, and storage of chemicals in quantities of 25 gallons/pounds or greater. The health department routinely inspects permitted chemical facilities within the community and coordinates monitoring and response with other government agencies.

Thorough knowledge of the chemical threats facing the community also allows LHDs to educate community members. LHDs tailor outreach activities for groups living near chemical facilities, teaching community members critical preparedness information including how to recognize the effects of chemical exposure, how to avoid exposure, and where to obtain information during an emergency.

Planning & Response In the case of a surreptitious chemical release, public health surveillance activities are crucial to determining that an event has happened, as well as the nature of the event. Routine passive surveillance results can be monitored for unusual symptoms associated with chemical exposures. LHDs also collaborate with poison centers, healthcare systems, and clinical laboratories on protocols for chemical exposure symptom recognition and reporting protocols.

Once it is known that an event has occurred, LHDs’ preexisting community relationships position them to be a trusted source of risk communications. While other responders handle the hazardous materials, LHDs have the ability to calm and inform the populace. By synthesizing knowledge of the chemical’s properties and the parts of the community affected, LHDsentify at-risk populations and share information on health concerns and protective measures, such as evacuation routes, shelter-in-place guidance, and instructions for decontamination and obtaining medical care. Health messages and templates for the most likely chemical threats can be drafted in advance, along with messaging for events when the chemical released is not immediately known.

Response partners also turn to LHDs for expertise on potential human health and environmental impacts of chemical agents. LHDs provide subject matter expertise to healthcare partners on matters such as the toxicity of chemical agents and sampling and screening approaches. If the agent is unknown, LHDs could use epidemiologic investigation methods to helpentify it. LHDs engage in active surveillance of cases through coordination with hospitals, emergency medical services, urgent care, and poison control centers, as well as coordination with sheltering partners to support the assessment, referral, and decontamination of exposed persons presenting at shelters. Other potential roles based on LHD expertise include: (a) coordinating the provision of mental and behavioral health services to affected communities; and (b) providing guidance to ensure the safety and health of on-the-ground responders.

Public health expertise on the impacts of chemical agents also provides extensive opportunities to support and collaborate with healthcare and environmental health partners. With large numbers of people (both injured and worried well) potentially reporting to hospitals, LHDs could assist with surge management by supporting triage and patient tracking efforts, or by monitoring bed status and other issues across multiple affected facilities and serve as a liaison between hospitals and response partners. Depending on how environmental health is handled in the jurisdictions, LHDs may play a role assessing and monitoring the environment impact of the agent and the pathways by which it travels. With their knowledge of environmental health impacts, LHDs define exclusionary zones and evacuation areas to ensure public safety, as well as to issue advisories related to drinking water and food safety.

LHDs also may be responsible for distribution and dispensing of medical countermeasures. Many LHDs are the lead agencies for CHEMPACK distribution. The rapid onset of chemical exposure symptoms means that medical countermeasures must be deployed quickly, but uncertain diagnoses can make the determination to dispense difficult. Public health understanding of chemical exposure symptoms and experience with medical countermeasure dispensing well positions LHDs to develop CHEMPACK deployment triggers and effective distribution protocols.

Once a response reaches the recovery phase, LHDs may be responsible for long-term monitoring of exposed individuals and environmental health impacts, as well as continued risk communication should environmental contamination linger. Their training and expertise again position them well to take on this role, although many LHDs lack the capacity to carry out these activities long-term without external support.

Challenges to Implementation The roles described above provide numerous entry points for public health participation in a large-scale chemical event response, butentifying roles is only the first step. NACCHO’s research revealed challenges to LHD involvement that also must be addressed. The first few are more easily addressed locally, but some require more systematic efforts at the state and federal levels to eliminate barriers.

  • Written plans. The process of developing written plans or annexes for chemical incident response helps LHDs more clearly define their response roles. By working with partners to develop written plans, LHDs set up protocols to ensure that the resources and capabilities they offer are available and utilized during a chemical response. Local best practices, such as chemical response annexes and decision trees, must be more widely shared to aid in written plan development.

  • Notification. The perception that chemical events only require a hazmat response interferes with the rapid involvement of LHD responders. It can be difficult toentify when an average hazmat incident crosses the line into an event with larger community consequences requiring public health involvement. Clear delineation of public health response roles and notification triggers are needed to ensure that LHDs are at the table when they need to be.

  • Information sharing. Once roles are defined, LHDs need to determine and share their data and communication needs. It may not be clear to partners which information LHDs need in order to make decisions and carry out their assigned responsibilities. For example, LHDs need a certain level of situational awareness to accomplish any public messaging roles and may require the collection of certain data to support long-term monitoring of health outcomes of those exposed.

  • Baseline data. Many communities do not know the top chemical vulnerabilities and threats to their jurisdictions. Some of these can be determined through direct planning with local facilities (per the Chemical Facilities Anti-Terrorism Act) and participation on Local Emergency Planning Committees. Others are more difficult or potentially impossible to determine – for example, it is hard to assess chemicals passing through a jurisdiction by road or railway. Baseline data on current levels of contamination also is lacking, making it difficult to assess environmental health and safety in the long term for areas affected by chemical events.

  • Training and educational resources. As other responders look to public health for expertise on chemical health threats, LHDs need regular training and education in this area, but budget limitations and conflicting priorities pose obstacles. Although LHDs may be well versed in the most likely chemical threats to their jurisdictions, it is impossible for them to maintain expertise in the thousands of chemical threats that exist. As such, LHDs must maintain an understanding of which questions to ask and who to contact to source information – for example, poison centers are a critical partner that LHDs help integrate into chemical response planning. LHDs have access to many resources of the Centers for Disease Control and Prevention as well as other federal resources used to support chemical incident response. However, different guidance from different federal agencies may be confusing, and certain resources, like plume modeling, may be unknown or unavailable to LHDs, especially ones that are smaller or underfunded.

LHDs have much to offer their response partners and communities with regard to preventing, responding to, and recovering from large-scale chemical incidents. However, more planning and partnership-building must take place before public health’s unique knowledge, skills, and resources can be effectively utilized in these scenarios. Further research may illuminate strategies for better integration of public health into chemical response activities. In the meantime, collaboration and communication to plan for the unique challenges posed by chemical incidents are the best way for communities to prepare.


For additional information: Florida Department of Health. (2012). Chemical Incident Annex to the Emergency Operations Plan.


Rachel Schulman, MSPH, CPH, is a senior program analyst with the National Association of County and City Health Officials (NACCHO). Her work supports strengthening relationships between public health and emergency management, improving public health’s chemical, biological, radiological, nuclear, and explosive (CBRNE) preparedness and response activities, and enhancing local public health all-hazards preparedness planning efforts through Project Public Health Ready. Previously, she served as an associate emergency planner at the Baltimore City Mayor’s Office of Emergency Management. She received her MSPH in health policy and Certificate in Public Health Preparedness from Johns Hopkins Bloomberg School of Public Health and her BA from Wesleyan University.