Industrial Hygiene SamplingIndustrial Hygiene SamplingExposure Assessment Sept 13, 2007Sept 13, 2007ObjectivesObjectives•Introduce“Industrial Hygiene”Introduce Industrial Hygiene• Establish context with respect to Risk AssessmentAssessment • Overview of Sampling–Purpose– Methods–Data•ImplicationspIndustrial HygieneDefinition•Industrial Hygiene:Science and artIndustrial Hygiene:Science and art devoted to the anticipation, recognition, evaluation prevention and control ofevaluation, prevention, and control of those environmental factors or stresses arising in or from the workplace which mayarising in or from the workplace which may cause sickness, impaired health and well being or significant discomfort amongbeing, or significant discomfort among workers or among citizens of the communitycommunity.Industrial HygieneIndustrial Hygiene•Sometimes referred to as“occupational“Sometimes referred to as occupational hygiene (e.g. UK)•Predates“Risk Assessment”as defined by•Predates Risk Assessment as defined by NASCbi l tfRikA t•Combines elements of Risk AssessmentComparison IH and Risk AssessmentIndustrial Hygiene Risk AssessmentAnticipation and Recognition Hazard IdentificationEvaluation Toxicity and Exposure Assessment and Risk CharacterizationControl Risk ManagementHazard Communication Risk CommunicationIndustrial Hygiene ExposureIndustrial Hygiene Exposure•Industrial Hygiene focus is on exposureIndustrial Hygiene focus is on exposure assessmentHistorically the occupational environment–Historically the occupational environment– Expanded to home and communityNote: As the applications of exposure data grew in various fields many new“specialties”grew in various fields, many new specialties formed ( i.e. environmental engineering, radiation safety, risk assessment etc) and y, )separated from Public HealthEvaluation -Air Sampling and Analysis“The purpose of industrial hygiene The purpose of industrial hygiene sampling is to represent the important components to theimportant components to the physiology of the worker and not to demonstrate the prowess of thedemonstrate the prowess of the chemist”SLIDE 7Paraphrase from HatchExposure Assessment OverviewExposure Assessment Overview•Exposure Assessment is NOT universallyExposure Assessment is NOT universally defined by users•Exposure is not DOSE but seeks to•Exposure is not DOSE but seeks to estimate itAhd l•Approaches and examples– Exposure Assessment in “Risk Assessment”– Occupational settingsEvolution of Exposure AssessmentEvolution of Exposure Assessment• 1920’s– Occupational Exposures began to be quantified and related to workplace health (risk)ResultExposure limit values–Result-Exposure limit values• 1950,60’s–Environmental concerns air and water pollutionEnvironmental concerns, air and water pollution– Waste site Clean-up• 1983– NAS “Risk Assessment Paradigm–“RAGS”Why is Exposure Important?HatchExposure Assessment GoalExposure Assessment GoalWe can also consider Impairment as a function of increasing DOSESLIDE 11DOSEPutting It All TogetherggExposure MeasurementExposure Measurement•Measurement at the point of contact whileMeasurement at the point of contact while exposure occurs•Estimation from a scenario that evaluates•Estimation from a scenario that evaluates contact variablesEti tdf bi k ltdt•Estimated from biomarkers related to uptakeEPA Exposure Assessment GuidelinePoint of Contact MeasurementsPoint of Contact Measurements•Advantages-•DisadvantagesAdvantages– Direct –Accounts for micro Disadvantages– Subject to analytical prowessenvironmental variablesSpecific to activity– Models can be incomplete or highly complex–Specific to activity level–Direct relationship to complex– Must be comprehensive or pbiomarkers– Preferred over modelsextrapolated to others–COSTIndustrial Hygiene SamplingUnique Value•Representative monitoring data isRepresentative monitoring data is preferred over models•Industrial Hygiene data gathering has a•Industrial Hygiene data gathering has a long history and extensive technologyR l t ifi ll t “ li it•Relates specifically to “exposure limit values” (TLV, PEL, OEL) • Relates to historical biomarker information (Biological Exposure Indices – BEI)IH DATA METRICSIH DATA METRICS•Time-weighted averageTimeweighted average• Peak ExposureSh tt•Short-term exposure• Units– Ppm v/v in air–Mg /M3g– Historical mmpcfExposure Assessment Strategy –IH P diIH ParadigmSLIDE 20AIHA GuidelinesExposure Assessment Strategy –IH ParadigmIH ParadigmSLIDE 21Some Exposure VariablesSome Exposure Variables•Acute ExposureAcute Exposure • Chronic Exposure • Source of the Agent• Pathway for ExposureSLIDE 22Exposure Assessment StrategyExposure Assessment StrategyTilTerminologySLIDE 23Occupational ExposuresOccupational Exposures• “Often” air mediated – emphasis on “air samplingpg• Usually a substantial dermal component that is not readily pycharacterized• “Skin notation”SLIDE 24STATES OF MATTERSTATES OF MATTER•DustDust• Fume Mi t•Mist • Vapor•Gas•AerosolAerosolWalk Through SurveyWalk Through Survey• Become familiar with plant processes• ID process chemicals and materials,•Observe worker activities Obse e o e act t es• ID and examine existing exposure controlsSLIDE 26exposure controls • Start data collection recordExposure Assessment StrategyIndustrial Hygiene MonitoringSLIDE 27SAMPLE ?SAMPLE ?•Why sample?•Why sample?• Who to sample?• Where to sample?•What to sample for?•What to sample for?• When to sample?• How long to sample?SLIDE 28Evaluation of Workplace Hazards–Evaluation of Workplace Hazards Characterization of the EnvironmentOBJECTIVES OF AIR SAMPLINGOBJECTIVES OF AIR SAMPLING (WHY)• Workplace CharacterizationI ti t l lit•Investigate employee complaints• Effectiveness of engineering controls• Effectiveness of administrative controls• Maintain a history of worker exposureSLIDE 29Step #2: Selecting Air SamplingStep #2: Selecting Air Sampling Methods•Inventory Chemicals / Agents to•Inventory Chemicals / Agents to which workers are exposedNb f l tb•Number of employees to be evaluated• Frequency of cyclic work process• Duration of exposure(s)SLIDE 30p()Step #2: Selecting AirStep #2: Selecting Air Sampling Methods• Consistency of exposuresyp• Mobility of workers in relation to processprocess•