# The Concentration of Oxygen Dissolved in Tissues at the Time of Irradiation as a Factor in Radiotherapy

Originally published in 1953, this seminal work by Gray first described oxygen’s ability to be a radiosensitizer for the treatment of solid tumors. Further work over the following decades has confirmed this observation. Gray later had a unit of measure named after him for his pioneering work – one Gray is defined as the absorption of one joule of radiation energy per kilogram of matter. Click here to read the publication.