Chemical and Biological Decontamination The University of South Alabama Center for Strategic Health Innovation © University of South Alabama Center For Strategic Health Innovation. All Rights Reserved. These slides are a part of the ARRTC program and cannot be reproduced for commercial purposes.

Chemical/Biological Release Acute and Delayed toxicity Routes of Exposure Inhalation** Absorption Ingestion Through open wound/Injection Local and systemic effects of exposure Dose response as it relates to risk assessment Synergistic effects of combined substances Assessment and use of toxicology information Relationship of proper decontamination to higher mortality and morbidity Alteration of triage patients as they relate to toxically exposed patients Levels of Personal Protective Equipment needed

Chemical Decontamination

Hospital Responsibilities According to JCAHO and OSHA, emergency departments (EDs) and emergency medical services (EMS) are responsible for managing potential chemical disasters (accidental and acts of terrorism) Three primary goals for hospitals exist during a chemical incident: Isolate the chemical contamination Appropriately decontaminate and treat the patient(s) while protecting hospital staff, other patients, and visitors Reestablish normal services as quickly as possible

Five Major Classes of Chemical Warfare Agents Nerve agents—tabun, sarin, soman, GF, and VX Cyanide gas Vesicants—sulfur mustard and lewisite Pulmonary agents—phosgene and chlorine Riot control agents—aka: tear gas; mace (CN), pepper spray, and CS

Goals of Decontamination Goals include: Reduce the amount of the agent Remove the agent Prevent further contamination of the environment Remember: The safety of the staff is highest priority Decontamination needs to occur as quickly as possible There is a direct relationship between contact time and effect (severity of signs and symptoms)

Methods of Decontamination Three basic methods— Physical removal Flushing with water or aqueous solution Absorbent materials M291 Resin Chemical methods Water/soap wash Oxidation Hydrolysis Hydrolyzing agents

Decontamination Procedures Assessment and “Size-up” incident Scene control/establishment of perimeter(s) Identify agent (if possible) Chemical detection paper can detect and identify airborne chemical warfare agents. The paper is impregnated with dyes sensitive to different types of chemical warfare agent, and will indicate which type of agent is present by its corresponding pigment signal. Determine the level of PPE required and don gear Prepare Decontamination area (Set-up Zones) Control access to the decontamination site as well as the hospital

Decontamination Procedures Setting up Decontamination Zones Three distinct zones must be established: Hot Zone Warm Zone Cold Zone

Decontamination Procedures

Decontamination Procedures Preparing decontamination area into zones Warm zone should be outside of facility Downwind of clean area (approximately 50-75 yards); not near facility air intake Area for decontamination triage Receptacles for contaminated clothing, valuables, and contaminated supplies Source of water (warm water is best, especially in cold climate areas), soap, and towels Tape to demarcate zones (dirty and clean areas) Screens for privacy or segregation by gender (if possible) Collection systems for runoff water Chemical agent monitoring (CAM) supplies

Decontamination Procedures Overview of Decontamination of victim(s): Is personnel, time, and equipment intensive Patient may be litter-bound or ambulatory Remove all clothing (reduces agent by 80-90%) Place all clothing and valuables in a bag Place these bags in a larger collection container (do not let bags touch the outside of the container) Wet skin, and wash down with soap and water (pay attention to hair, face, hands) for at least 5 – 10 minutes; then RINSE! RINSE! RINSE! Check for the presence of agent by using CAM or M-8 paper; If positive, decontaminate again If negative, relocate to clean area, don dry clothing

Mass Decontamination

Decontamination Procedures: Selecting a Decontamination Agent Many substances have been evaluated for their usefulness in skin decontamination. The most common problems with potential decontaminants are irritation of the skin, toxicity, ineffectiveness, or high cost. Recognized desirable traits of a skin decontaminant include the following: Neutralization of all agents Safety (compound to be both nontoxic and non-corrosive) Ease of application by hand Readily available Rapid action Non-production of toxic end products Stability in long-term storage Short-term stability (after issue to unit/individual) Affordability Non-enhancement of percutaneous agent absorption No irritability Hypoallergenicity Ease of disposal

Decontamination Procedures: Selecting a Decontamination Agent Liquid Decontamination Agent of Choice: Household bleach (Hypochlorite)--inexpensive Two concentrations commonly used 0.5% solution —works by physically removing, oxidizing, and/or hydrolysis of the agent. Can be used to decontaminate the skin and soft-tissue injuries Must be rinsed thoroughly from the skin Should not be used for penetrating wounds leading into a cavity (e.g., abdominal and chest wounds) or in the eyes 5.0% solution —works by physically removing, oxidizing, and/or hydrolysis of the agent Should only be used to decontaminate inanimate objects

Decontamination Procedures: Selecting a Decontamination Agent Dry Decontamination Agent of Choice: Chloride of lime and magnesium oxide—this mixture creates a powder (must be finely ground) that provides both absorption and neutralization agents. The powder can be used to decontaminate skin and equipment. Flour—effective against GD, VX, and HD. The flour is applied to the skin then wiped off with wet tissue paper. M291 Resin—developed and used by the military; is the best skin decontamination agent known; used for spot decontamination only.

Biological Decontamination

Biological Exposure Biological weapons may expose people to bacteria, viruses, or toxins as fine airborne particles. Biological agents are infectious through one or more of the following mechanisms of exposure, depending upon the particular type of agent: inhalation, with infection through respiratory mucosa or lung tissues; ingestion; contact with the mucous membranes of the eyes, or nasal tissues; penetration of the skin through open cuts (even very small cuts and abrasions of which employees might be unaware).

Typical Biological Warfare Agents Anthrax Staphylococcal Enterotoxin B (SEB) Bubonic/Pnuemonic Plague Cholera Smallpox Other bio-engineered agents

Decontamination of Biological Agents Environment infected with a biological agent can be decontaminated with a diluted solution of household bleach (sodium hypochorite). If agent is a virulent bio-agent, full strength sodium hypochorite may be used. Although not all types of bio-agents will be immediately killed by bleach, it may prevent the spread of the contaminant