Data Limitations: The quality and quantity of available data can be a major source of uncertainty. Often, toxicologists rely on
animal studies or limited human data, which may not always accurately predict human responses.
Inter-species Variability: Differences between species mean that results from animal studies may not be directly applicable to humans. Toxicologists use uncertainty factors to account for these
variabilities.
Intra-species Variability: Even within the same species, individuals may respond differently to chemical exposures due to genetic differences, age, gender, and health status.
Exposure Assessment: Estimating the level, frequency, and duration of human exposure to chemicals can be challenging, adding another layer of uncertainty.
Modeling and Extrapolation: Predictive models and extrapolation from high-dose studies to low-dose human exposures can introduce
uncertainties.
Mechanistic Understanding: Limited knowledge about the
mechanisms of action of certain chemicals can hinder accurate risk predictions.
