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EPA ExpoBox

Exposure Assessment Tools by Tiers and Types

Exposure assessment is one of the four major steps in risk assessment; others include hazard identification, dose-response assessment, and risk characterization.

Exposure may be estimated using one of several assessment tiers or types: screening-level and refined, deterministic and probabilistic, or aggregate and cumulative. Alternatively, exposure assessments may be categorized according to exposure assessment approaches, exposure media, exposure routes, lifestages and populations, or chemical classes.

Screening-Level and RefinedScreening -Level and Refined

See information and tools related to screening-level and refined


Deterministic and ProbabilisticDeterministic and Probabilistic

See information and tools related to deterministic and probabilistic


Aggregate and CumulativeAggregate and Cumulative

See information and tools related to aggregate and cumulative

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