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NEW ERA
Part 2: Evolving Methods
and Future Directions
BY PAMELA R. D. WILLIAMS, G. SCOTT DOTSON AND ANDREW MAIER
Editor’s note: This article is the second in a series sponsored by the AIHA Risk Assessment Committee intended to highlight research and
policy initiatives that are shaping the future of risk assessment in the industrial hygiene profession. Part 1 appeared in the April 2012 issue.
For more than three decades, health practitioners and regulatory agencies have
used risk assessment methods
to characterize health risks.
Risk assessment is the process
of determining the likelihood
and severity of health risk to an
individual or population from
exposure to a chemical or other
stressor.1,2 Evolving methods and
advances in science and technology offer several opportunities
for improving risk assessment
and its application to occupational settings.
Cumulative Risk Assessment (CRA)
Broader in scope than traditional chemical risk assessments, CRAs determine
which chemicals, stressors or other risk
factors are affecting certain populations. They address multiple chemical
and non-chemical stressors, aggregate
exposures and risks (that is, exposure
to a single stressor by multiple routes),
and combined risks for common health
end points by chemical or stressor
groupings. 3, 4
The EPA framework for conducting
CRAs involves planning, scoping and
problem formulation; analysis; and in-
terpretation and risk characterization. 5, 6
This framework has been applied to
CRAs of chemicals, such as organo-
phosphate pesticides and phthalates. In
addition, EPA has developed various
models and web-based tools to assess
aggregate and cumulative exposures
and risks. 7, 8
Biomonitoring
Biomonitoring assesses human exposure by measuring chemicals or
their metabolites in human tissues or
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