PLoS ONE

Fryer HR, McLean AR (2011) There Is No Safe Dose of Prions. PLoS ONE 6(8): e23664. doi:10.1371/journal.pone.0023664

Understanding the circumstances under which exposure to transmissible spongiform encephalopathies (TSEs) leads to infection is important for managing risks to public health. Based upon ideas in toxicology and radiology, it is plausible that exposure to harmful agents, including TSEs, is completely safe if the dose is low enough. However, the existence of a threshold, below which infection probability is zero has never been demonstrated experimentally.