Inhalation and developmental toxicity of select chalcogenide engineered nanomaterials

Due to their small size nanomaterials pose certain health risks that materials of the same chemical composition but a large size simply do not. Because of this, it is necessary to investigate the potential health outcomes that arise due to their exposure. One such class of nanomaterials used across a variety of consumer and industrial sectors is chalcogenides. Knowledge surrounding the toxicity of chalcogenide-based nanomaterials is relatively thin, especially when considered through the lenses of developmental and inhalation toxicology. Due to this knowledge gap, this work implemented schemes that targeted both inhalation and developmental endpoints. We found that toxic outcomes are highly material specific but may be predicted by solubility in biological fluids. Studies of chalcogenide materials that produced toxic outcomes upon inhalation did so via pulmonary inflammation. Additionally, major developmental defects did not occur as a result of perinatal chalcogenide nanomaterial exposure. Postnatal exposure led to pulmonary inflammation in exposed model populations. Also, some exposures caused asthma outcomes to worsen in perinatally exposed groups even though the initial pulmonary inflammation had resolved. This work leads to the conclusion that toxic outcomes are based upon material composition and not necessarily the nano scale of the materials. And those materials that caused pulmonary inflammation did not cause direct developmental toxicity, but rather caused additional pulmonary inflammation during the postnatal period that altered responses in the mature population.