Science Wednesday: Risk Assessment In Every Day Life

Each week we write about the science behind environmental protection. Previous Science Wednesdays.

Whenever someone in my office says, “You’d be the perfect person for…,” my first thought is always this can’t be good. But when the “perfect” assignment was an invitation to teach 7th and 8th grade scientists attending the Summer Educational Development Program about what my colleagues and I do at EPA’s National Center for Environmental Assessment (NCEA), I immediately agreed.

My next thought, however, was “how do I make Human Health Risk Assessment , interesting to 12- and 13 year-olds?” Yikes!

I decided to start the conversation about risks the students might face in every day life. Things like traffic and playing sports on hard asphalt. Or sharks. We went from there to discuss how one might reduce these every day risks, or “risk management” in the form of using crosswalks or the help of crossing guards.

We then talked about how we at EPA use the NAS Risk Assessment paradigm (hazard identification, dose-response analysis, and exposure assessment) to determine chemical risk. I used the shark example to explain the need to consider both “hazard” and “exposure” in risk assessment. While a hungry shark may be a hazard, we all agreed that there’s not much an exposure risk to us in the classroom. (Well at least we hoped not!).

With no sharks to worry about, I moved the discussion to something we here at EPA are more concerned about: lead. In the context of the four-step risk assessment paradigm, we explored the human health risk assessment of lead to describe determining hazards and risk levels that would result from various exposures.

To end, we talked about how genetics might make one population more susceptible to exposure risk than another population. Using a simple experiment on taste, everyone determined if they were a genetic ‘Taster’ or ‘Non-Taster.’ We talked about how if being a ‘Taster’ was a risk, and only three people in the class can ‘Taste,’ than identifying their presence would impact a risk assessment. This helped the students grasp the importance of understanding susceptible populations in risk assessment, and how smaller subpopulations may be impacted by risks not generally seen in the bigger population.

The energy and enthusiasm that the class brought to the discussion, and their quick understanding of the importance of risk assessment made me all the more energized about what I do every day. I am looking forward to my next perfect assignment.

About the author: Dr. Maureen Gwinn is a toxicologist with the National Center for Environmental Assessment in the Effects Identification and Characterization Group where she works in Human Health Risk Assessment. Dr. Gwinn enjoys doing toxicology outreach with students through the Society of Toxicology’s Education Committee.