Can we detect enzyme inhibition in waste water?
In order for our show we had a functional prototype, we needed to show enzyme inhibition in waste water. We performed this experiment using triplicates of 15 nM P. falciparum FabI. It appears as if life is a bit slower in waste water…
This shows that our biosensor works in waste water!
When we first started our project, we took a trip to our local Safeway to catalog products containing triclosan. We discovered that many products had already phased out triclosan; some labels even read “Triclosan Free.” Although triclosan had been removed from products, many of them had simply replaced it with a different antimicrobial.
This trend reminded us of what Arlene Blum told us about how when chemicals are removed from use manufacturers look for a replacement; but because these chemicals need to serve similar functions they often have similar structures, and thus similar consequences. What results is a cycle whereby one toxic chemical is replaced by another toxic chemical.
We didn’t want to raise fear over triclosan use and contribute to this cycle. Instead we wanted to raise awareness around appropriate chemical use and reduce the use of chemicals in cases where there is no proven benefit.
This lead us to supplementing our triclosan biosensor with an, “antimicrobial footprint app,” to get consumers thinking about whether antimicrobial agents are even warranted in consumer products.
We designed our app as a heuristic to raise awareness about the unnecessary ubiquity of antimicrobials in consumer products. In the app, the user can click on an “About” tab to learn more about antimicrobials and how to be a responsible consumer. They can then go on to calculate their “Antimicrobial Footprint.” The user is able to click on antimicrobial containing products that they use, and see how it affects their total footprint. After using the app’s antimicrobial calculator to calculate their footprint, the user can submit their footprint along with their location. On the final page of the app the user is able to see how their footprint compares to the average footprint of other users. The submitted data is used to calculate this average, as well as to create a heat map of antimicrobial usage in the United States. This is another deliverable that users can look at to become more educated consumers.
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How It Works:
To create the antimicrobial calculator we found data on the levels of triclosan in selected consumer products, given in g triclosan/g products. We also found data on the daily use rates of consumer products, given in g triclosan/day. By combining this information we were able to calculate the users’ “antimicrobial footprint,” in grams triclosan/day. The app will also give you this metric in grams triclosan/year.
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Lesson Plan Sources:
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Footprint App Sources:
Rodricks, Joseph V. "Triclosan: A Critical Review of the Experimental Data and Development of Margins of Safety for Consumer Products." Critical Reviews in Toxicology, 2010. Web.