John Balbus, M.D., M.P.H., is Chief Health Scientist.

A new paper by Shaw et al., published in May in the Proceedings of the National Academy of Sciences, “suggests a generalizable and scalable method for the systematic characterization and comparison of novel nanomaterials” using high throughput in vitro tests.  Does this mean that the National Academy of Sciences’ vision for toxicity testing in the 21st century – proposed for conventional chemicals – is already here for nanomaterials?  Not quite.  Read more »

John Balbus, M.D., M.P.H., is Chief Health Scientist.

EPA’s recently released draft Nanotechnology Research Strategy (NRS) proposes a tiered testing system to evaluate human toxicity of nanomaterials.  It puts in vitro tests, or those done in test tubes and petri dishes as opposed to living animals, front and center.  EPA says the results of the first, in vitro tier will be used for guidance on “what health endpoints to monitor” and the second, in vivo tier will then help “identify those in vitro assays that correlate with in vivo nanomaterial toxicity or health effects.”

Wait a second.  If the in vivo testing is necessary in order to figure out what the in vitro testing results really mean, how can the agency use the in vitro testing results to figure out what health endpoints to monitor?  This cart and horse confusion is a serious matter. Read more »