Dr Helinor Johnston is an associate professor of toxicology at Heriot Watt University and specialises in the assessment of nanomaterial hazard to human health and the environment. Her current research focuses on investigating the suitability ofemploying alternative, non-rodentmodels to screen nanomaterial safety (e.g. in vitro models and zebrafish larvae) at different target sites including the lung, liver, intestine, skin and immune system. She is also involved in research projects which investigate the mechanism of nanomaterial toxicity and develop evidence based testing strategies that will allow toxicity assessments to be quicker, cheaper, more ethical and efficient. More recently she has led research activities which aim to better understand how the source of air pollution emissions influences the toxicity of particulate matter, with a focus on the adverse health impacts of air pollution in Thailand. Finally, she investigates the efficacy and safety of nanomedicines (e.g. that treat or diagnose cancer, infectious diseases and cardiovascular disease).  Helinor was previously a scientific advisor at DEFRA and worked as a post-doc on desk based projects which identified knowledge gaps in nanotoxicology in order to prioritise future research. Helinor’s PhD evaluated the toxicity of nanomaterials to the liver using in vitro models (Edinburgh Napier University).