The toxicity, transport and uptake of nanoparticles in the in vitro BeWo b30 placental cell barrier model used within NanoTEST.

Despite the rapid ongoing expansion in the use of nanomaterials, we still know little about their biological interaction and biodistribution within the human body. If medically relevant nanoparticles can cross specific cell barriers they may disseminate through the body beyond the original target and may reach particularly sensitive areas such as the foetus. This study utilised an in vitro barrier model of the placenta to explore toxicity, uptake and transport of iron oxide and silica nanoparticles. The findings indicate that these nanoparticles can transfer extensively across the placental barrier model but physico-chemical characteristics such as surface chemistry impact upon both uptake and transport. Iron oxide cytotoxicity was evident at lower doses and shorter exposure compared with silica and may be of clinical relevance. In vivo correlation of in vitro findings is essential but in vitro models may provide worst case-exposure estimates to help reduce the amount of testing required.