HESI Risk Assessment in the 21st Century (RISK21) Project



The HESI RISK21 Committee held its first Risk Assessment Summit on February 18-19,2020, in Washington, DC!

The Summit convened a broad group of stakeholders to discuss risk assessment approaches that ascribe to the following general principles:

  • Problem formulation-based
  • Risk-based at each step
  • Fit for purpose
  • Utilization of existing information
  • Transparent
  • Visual

Presentations and posters from the Summit are available here!

About RISK21®


Harmonize the approach to how the world evaluates chemicals using a risk-based approach.

Principles of RISK21®

Problem-formulation based
Risk-based at each step of the process
Use of prior knowledge
Fit for purpose
Value of information
“Enough precision to make the decision”
Provide a framework that is flexible, transparent, visual


Developed a risk assessment approach that embraces advance in scientific knowledge and methods
Actively involved over 120 participants (government, industry, academia, NGOs) through 6 years of work
Published 8 manuscripts in Critical Reviews in Toxicology
Reached over 500 participants in 5 countries on three continents via 7 hands-on case-study workshops
Revised current thinking about how to approach the science and art of risk assessment

Next Steps

Continued outreach and communication
Additional illustration and application via case studies
Ongoing dialog on advances and needs


Version 2.0 of the RISK21® Webtool is Now Available!

21st Century Framework

The webtool supports a problem formulation-based, exposure-driven, tiered acquisition approach that leads to an informed decision.

Transparent and Consistent

The webtool approach allows users to  optimize the use of resources and information available for chemical risk assessment.

Create Custom Plots

Users can interact with the RISK21 webtool application to visualize their own risk data, creating a custom plot which will be displayed on the screen.

RISK21® Roadmap and Matrix

The RISK21 webtool application allows users to input estimated exposure and toxicity data for each chemical, and will plot the intersection area, overlaying a risk matrix represented as a heat map.