Toxicity is an aspect of chemistry and biology that looks at “the level of harm” a substance can cause to us or the environment. Nanotoxicity, determines if nanoparticles are dangerous, and if dangerous, assesses how much harm these particles can bring. Many scientists including Dr. Aaron Schultz do research into this area, also looking at how these chemicals can build up over time, to potentially become more dangerous. This area focuses on how dangerous these substances might become. In this section we develop an understanding of the size of nanoparticles, how these particles can build up and harm animals like the zebrafish, and investigate how these small particles can get through the barriers in our body.

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