Science Wednesday: Tox21’s 10,000 Compound List

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By Aaron Ferster

I’m a big fan of those “Top Ten” lists that come out at the end of every year. I like to track how many of my favorite movie critic’s Top Ten List of Films I’ve caught during the year (so far, I’ve seen most of them—and I’ve still got a couple of weeks to go before New Year’s Eve). The synopses included in the lists of Top Ten Best Novels of the year let me feel like I’m in the know about the latest literature, even though I’ve clearly spent more time at the cinema than at the bookstore.

But this year the most impressive “list” I’ve come across came out last week, when EPA and its partners from the National Institutes of Health and the U.S. Food and Drug Administration announced the compounds to be tested as part of the collaborative Tox21 research program over the next couple of years

Only the list is slightly more robust than ten—it’s a 10,000 compound library.

The library contains chemicals covering a wide variety of classifications, including chemicals found in industrial processes, consumer products, and food additives, as well as human and veterinary drugs. A large number of reference compounds are also included to give researchers access to different toxicological or disease endpoints, duplicate compounds for evaluating test methods, and a small set of chemical mixtures for a pilot study.

“The Tox21 partnership integrates revolutionary advances in molecular biology, chemistry, and computer science to quickly and cost-effectively screen the thousands of chemicals in use today,” said Paul Anastas, Ph.D., the Assistant Administrator for EPA’s Office of Research and Development.

The compounds will be tested with a high-speed, robotic testing system that was unveiled early this year—the subject of a previous blog post here on Science Wednesday.  That means the tests will continue nearly nonstop, 24-7 until all the compounds have been analyzed.

Results of the tests will provide information useful for evaluating if any of the 10,000 chemicals have the potential to disrupt processes in the human body to an extent that would lead to adverse health effects. I’ll be sure to blog about those results once they start rolling in. But in the meantime, I’ll be at the movies.

About the author: Aaron Ferster is the senior science writer for EPA’s Office of Research and Development, and the editor of Science Wednesday.

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