Human tissue is bombarded by a huge range of chemicals. Our lungs are inhaling pollution from both stationary and mobile sources as well as inhaled nanoparticles (NPs) and therapeutic products designed to provide new and innovative medical solutions. Our challenge is to identify what exposures are putting us at risk and balance the risk against benefits that we may receive from these chemicals and new products. Advances inin vitrocell culture technology may provide some of the answers. Regulatory toxicologists and health and safety professionals need rapid and reliable information on hazard profiles of chemicals to be able to assess the risk and manage potential exposures to harmful materials. in vivo studies require a large number of expensive, time consuming and in some cases non humane tests in animal species. Recent innovations in human cell culture exposure and test systems has allowed the development ofin vitro assay systems that are predictive, representative and suitable for toxicity screening of a diverse range of chemicals including airborne materials and nanomaterials (NMs). Innovative in vitro exposure techniques that have been developed to provide direct exposure of human lung cells to inhaled materials and nanomaterials will be discussed. Further development and validation of such test systems are crucial for evidence based safety evaluation and risk assessment of inhaled materials, nanomaterials and therapeutic products.