Similar structure – both types of risk assessments consist of a problem formulation, hazard assessment, exposure assessment and risk characterization.
Both can use models to estimate exposure to receptors (i.e., human health risk assessment assess exposure to humans via ingestion, inhalation and dermal contact, while ecological risk assessments may assess exposure to terrestrial animals via ingestion).
Both compare measured environmental chemical concentrations against environmental quality guidelines in the problem formulation phase.
Ecological risk assessment exposure models are like human health risk assessment exposure models, but only consider ingestion pathways to terrestrial animals. The same models also consider foraging range for animals. Foraging range not considered in human health risk assessments.
Larger reliance on signs of impacts (i.e., toxicity studies, measurements of fish health, aquatic insect surveys, visible abnormalities on amimals or discoloration of plants).