Assessing Chemical Exposure: A Lab Perspective

Assessing Chemical Assessing Chemical Exposure:Exposure:

A Lab PerspectiveA Lab Perspective

Kevin Chao, Ph.D.Kevin Chao, Ph.D.Department of Public HealthDepartment of Public Health

State of CaliforniaState of California

Topics CoveredTopics Covered

Introduction to All Hazards TerrorismIntroduction to All Hazards Terrorism Chemical Terrorism SpecificsChemical Terrorism Specifics Toxicology/Properties of likely agentsToxicology/Properties of likely agents Public Health/Laboratory responsePublic Health/Laboratory response Environmental and clinical sample Environmental and clinical sample

collectioncollection Environmental and clinical sample Environmental and clinical sample

testingtesting

All Hazards?All Hazards?

ChemicalChemical BiologicalBiological RadiologicalRadiological NuclearNuclear ExplosiveExplosive

Toxic Industrial ChemicalsToxic Industrial Chemicals

ChlorineChlorine Hydrogen CyanideHydrogen Cyanide AmmoniaAmmonia PhosgenePhosgene Methyl IsocyanateMethyl Isocyanate

Bhopal, IndiaBhopal, India

December 3, 1984December 3, 1984 40 Tons of MIC (methyl isocvanate)40 Tons of MIC (methyl isocvanate) 500,000 exposed (500,000 exposed (5-8 miles downwind5-8 miles downwind)) 11,000 disabled11,000 disabled 3,800 dead3,800 dead

Similar Chemical Incident in Similar Chemical Incident in California?California?

Metam SodiumMetam Sodium Where did it happen?Where did it happen? Lucky or what?Lucky or what?

Comparative ToxicityComparative Toxicity(lethal dose)(lethal dose)

Highly Toxic AgentsHighly Toxic AgentsDeveloped to Kill or DisableDeveloped to Kill or Disable

Advantages:Advantages: Small amounts neededSmall amounts needed Surreptitious useSurreptitious use Targeted useTargeted use

Disadvantages:Disadvantages: ““Harder” to obtainHarder” to obtain Nations?Nations? Cults?Cults? Lunatics?Lunatics?

Some Overt Exposure ScenariosSome Overt Exposure Scenarios

Blast, leakBlast, leak Ventilation ductsVentilation ducts Closed spaces:Closed spaces:

• • subway carssubway cars

• • planesplanes Vehicular releases:Vehicular releases:

• • drive-bydrive-by

• • crop dustingcrop dusting

Some Covert Exposure ScenariosSome Covert Exposure Scenarios

Food, tobacco, alcoholFood, tobacco, alcohol Medications, blood productsMedications, blood products Cosmetics and personal hygieneCosmetics and personal hygiene

productsproducts Surfaces (door knobs, utensils):Surfaces (door knobs, utensils):

hand-to-mouthhand-to-mouth Fixed distribution systems: water,Fixed distribution systems: water,

natural gasnatural gas

Respiratory Irritant GasesRespiratory Irritant Gases

ChlorineChlorine PhosgenePhosgene Oxides of nitrogenOxides of nitrogen AmmoniaAmmonia Hydrogen chlorideHydrogen chloride FormaldehydeFormaldehyde AcroleinAcrolein

Respiratory Irritant GasesRespiratory Irritant Gases

Direct chemical reaction withDirect chemical reaction with

tissuestissues pH, redox, addition, substitutionpH, redox, addition, substitution

reactionsreactions structural lipids and proteinsstructural lipids and proteins

denatured or degradeddenatured or degraded Induced inflammatory reactionInduced inflammatory reaction

Metabolic ToxicantsMetabolic Toxicants

CyanidesCyanides AzidesAzides SulfidesSulfides Carbon monoxideCarbon monoxide FluoroacetatesFluoroacetates Dinitrophenol, pentachlorophenolDinitrophenol, pentachlorophenol Many othersMany others

Cyanide: ToxicologicalCyanide: ToxicologicalMode of ActionMode of Action

Blocks electron transport in Blocks electron transport in mitochondriamitochondria

Binds to Fe+3 in cytochrome oxidaseBinds to Fe+3 in cytochrome oxidase Prevents electron transfer to oxygenPrevents electron transfer to oxygen Oxygen-rich red venous bloodOxygen-rich red venous blood

Carbon MonoxideCarbon Monoxide

#1 chemical cause of acute toxic death#1 chemical cause of acute toxic death #2 rank air pollutant after CO2#2 rank air pollutant after CO2 Vehicular, coal/oil burning, industrialVehicular, coal/oil burning, industrial Invisible, odorlessInvisible, odorless Affinity for Hgb 220x greater than that of O2Affinity for Hgb 220x greater than that of O2 Forms carboxyhemoglobinForms carboxyhemoglobin Proportionately decreases oxygen carryingProportionately decreases oxygen carrying

capacitycapacity Red venous bloodRed venous blood

Vesicant AgentsVesicant Agents(Blister Agents)(Blister Agents)

Mustard agentsMustard agents

• • Sulfur (military use)Sulfur (military use)

• • Nitrogen (chemotherapy)Nitrogen (chemotherapy) LewisiteLewisite

(2-chlorovinyl dichloroarsine)(2-chlorovinyl dichloroarsine)

Mustard: TargetsMustard: Targets

Nerve AgentsNerve Agents

A family of agents that kill byA family of agents that kill by

destroying acetyl cholinesterase, andestroying acetyl cholinesterase, an

enzyme essential for proper nerveenzyme essential for proper nerve

functionfunction

Physical PropertiesPhysical Properties

Liquids at room temperature - not gasesLiquids at room temperature - not gases Soluble in fat and waterSoluble in fat and water Absorbed through respiratory tract, skin,Absorbed through respiratory tract, skin,

eyeseyes Phosphonate estersPhosphonate esters Tabun (GA) - most unavailableTabun (GA) - most unavailable Sarin (GB) - most volatileSarin (GB) - most volatile Soman (GD) - fastest “aging”Soman (GD) - fastest “aging” VX - most potent and persistentVX - most potent and persistent Other nerve agentsOther nerve agents

Symptoms of Nerve AgentsSymptoms of Nerve Agents

““DUMBELS”DUMBELS” D - DiarrheaD - Diarrhea U - UrinationU - Urination M - MiosisM - Miosis B - Bronchoconstriction, BronchorrheaB - Bronchoconstriction, Bronchorrhea E - EmesisE - Emesis L - LacrimationL - Lacrimation S - SalivationS - Salivation

What plant is this?What plant is this?

Public Health AimsPublic Health Aimsin a Chemical Eventin a Chemical Event

Identify the agent or causeIdentify the agent or cause Circumstance, intelligence, clinical Circumstance, intelligence, clinical

syndromesyndrome Environmental or biological fluids assayEnvironmental or biological fluids assay Determine temporal or geographicalDetermine temporal or geographical

distribution of exposuredistribution of exposure Determine relative (high/low) exposuresDetermine relative (high/low) exposures

Public Health AimsPublic Health Aimsin a Chemical Event (cont.)in a Chemical Event (cont.)

Evaluate health implicationsEvaluate health implications Provide medical and public healthProvide medical and public health

guidance and supportguidance and support Provide continued surveillance andProvide continued surveillance and

preventionprevention

After a CT IncidentAfter a CT IncidentEnvironmental Samples:Environmental Samples:

Identify chemical agent on sceneIdentify chemical agent on scene Define contamination zoneDefine contamination zone Check for effectiveCheck for effective

decontaminationdecontamination Determine when to allow re-entryDetermine when to allow re-entry

Who collects the environmental Who collects the environmental samples?samples?

Hazmat TeamHazmat Team CST Team, request through State OESCST Team, request through State OES FBI Team FBI Team Standard procedures for collecting these Standard procedures for collecting these

samples as described in HAZMAT samples as described in HAZMAT handbook with proper PPE and handbook with proper PPE and precautionprecaution

What types of samples are needed?What types of samples are needed?

Sample types: solid, liquid, wipes and airSample types: solid, liquid, wipes and air

Who is going to test them for Who is going to test them for you?you?

Agencies may test them for you:Agencies may test them for you: -Cal EPA (DTSC)-Cal EPA (DTSC) -US EPA-US EPA -LLNL for warfare agents-LLNL for warfare agents -CDHS could also help-CDHS could also help

After a CT IncidentAfter a CT IncidentClinical Samples:Clinical Samples:

Confirm agent IDConfirm agent ID Assist in medical treatmentAssist in medical treatment Separate exposed from “WorriedSeparate exposed from “Worried

Well”Well” Support health effect studiesSupport health effect studies

Continues:Continues:

Predicting levels of toxicants inPredicting levels of toxicants in

people using environmentalpeople using environmental

monitoring is very difficult andmonitoring is very difficult and

includes many assumptions…includes many assumptions…

Bio-monitoring- MeasuringBio-monitoring- MeasuringChemicals in PeopleChemicals in People

California has the funding to start a bio-California has the funding to start a bio-monitoring program as a tool to assess monitoring program as a tool to assess human exposure to toxic chemicals in human exposure to toxic chemicals in CaliforniaCalifornia

Your Plan for Human SpecimensYour Plan for Human Specimens

Local HAZMAT/first respondersLocal HAZMAT/first responders

identify or suspect incidentidentify or suspect incident Jurisdiction or FBI notifies CDHS/CDCJurisdiction or FBI notifies CDHS/CDC

Who collects the clinical Who collects the clinical samples?samples?

Attending physicians at ED to order the Attending physicians at ED to order the collection of clinical specimens (three collection of clinical specimens (three purple, one green and 25 cc urine for purple, one green and 25 cc urine for adults; urine only for infants and young adults; urine only for infants and young children) to be collectedchildren) to be collected

PH Labs as a hub to collect and ship PH Labs as a hub to collect and ship initial samples to CDHS/CDC pending initial samples to CDHS/CDC pending discussiondiscussion

What does CDC do with the first 40 What does CDC do with the first 40 samples?samples?

CDC performs PCR and “Rapid ToxicCDC performs PCR and “Rapid Toxic

Screen” on initial samplesScreen” on initial samples CDC provides guidance to LRN forCDC provides guidance to LRN for

analysis of remaining samplesanalysis of remaining samples

Rapid Toxic ScreenRapid Toxic Screen

Analysis of 40 samples for 150Analysis of 40 samples for 150

agents or metabolites within 36 hrsagents or metabolites within 36 hrs CDC has greater “screening”CDC has greater “screening”

capability than currently available atcapability than currently available at

any city or state public health labany city or state public health lab

Collecting Clinical Specimens:Collecting Clinical Specimens:

Protocols for collecting and shippingProtocols for collecting and shipping

blood (3 purple and 1 green) and urine blood (3 purple and 1 green) and urine (25 mL) (2 blank tubes and cups are (25 mL) (2 blank tubes and cups are required) posted onrequired) posted on

CDC’s website:CDC’s website:

http://www.bt.cdc.gov/labissues/http://www.bt.cdc.gov/labissues/

pdf/chemspecimencollection.pdfpdf/chemspecimencollection.pdf

Collecting Clinical Specimens:Collecting Clinical Specimens:

Clinical specimens will beClinical specimens will be

collected at hospitalscollected at hospitals Local Public Health Lab should continue Local Public Health Lab should continue

train hospital staff (ED nurse managers train hospital staff (ED nurse managers especially) on what clinical samples especially) on what clinical samples should be collected.should be collected.

Call Kevin Chao for resources may be Call Kevin Chao for resources may be able to test the samples at 510-377-3435able to test the samples at 510-377-3435..