Health Assessment and Contaminants: Workshop on pathways of human exposure Juliana Grant, MD MPH Agency for Toxic Substances and Disease Registry Regional Representative - Alaska

Outline Introduction to health assessment and pathways of human exposure Case study Applying exposure pathways Additional resources

Public Health Assessment ATSDR term for process of evaluating environmental contaminants and determining whether they are impacting human health Multi-step process Includes evaluating pathways of human exposure

Are humans exposed? Gold ore smelter Mercury released in smoke Acidic wastewater released into river Are humans exposed?

Pathway of Human Exposure Describes how people come into contact with contaminants from a specific source Useful for Understanding exposures Doing environmental sampling Developing interventions

No one drinks from it or swims in it Example pathways Breathing Smoke Air Nearby residents No one drinks from it or swims in it No one exposed Waste water River

Parts of pathways Source Media Point of exposure Route of exposure Exposed population

Parts of pathways Source Media Point of exposure Route of exposure Exposed population What How Who

Example parts of pathways Source Media Point of exposure Route of exposure Exposed population Drums Old buildings Oil spill Lead paint Air Soil Water Food At home Schools At mine or dump site Breathing Eating Contact with skin School children Workers Subsistence users Everyone

Case study: Open dump site What exposures from the Toksook Bay dump site are you most concerned about?

Applying exposure pathways Clear description of potential exposures Which contaminants are most concerning Examine how contaminants change as they move through environment Environmental sampling Where, When and What to sample

Applying exposure pathways Interventions Remove any part of pathway and exposure stops Information gaps What do we not know? Analyzing environmental data If exposure pathway is complete, is the exposure dangerous?

More information ATSDR website (www.atsdr.cdc.gov) Public Health Assessment Guidance Manual ToxProfile ToxFAQs

Juliana Grant 907-271-4073 jgrant@cdc.gov www.atsdr.cdc.gov Thank you! Juliana Grant 907-271-4073 jgrant@cdc.gov www.atsdr.cdc.gov

Dump site example Complete pathway Source Media Point of exposure Route of exposure Exposed population Trash at dump site Smoke from burning School children Nearby school Breathing Complete pathway

Only burn when wind blowing away from school Dump site example Source Media Point of exposure Route of exposure Exposed population Dump site Smoke from burning Only burn when wind blowing away from school Incomplete pathway