Generally, in the radiopharmaceutical industry, enriched water (H2Ω) is bombarded with hydrogen ions in either a cyclotron or linear accelerator, producing fluorine-18.
[3] In ice cores, mainly Arctic and Antarctic, the ratio of 18O to 16O (known as δ18O) can be used to determine the temperature of precipitation through time.
It was demonstrated that, under preindustrial atmosphere, most plants reabsorb, by photorespiration, half of the oxygen produced by photosynthesis.
[7][8] Fluorine-18 is usually produced by irradiation of 18O-enriched water (H218O) with high-energy (about 18 MeV) protons prepared in a cyclotron or a linear accelerator, yielding an aqueous solution of 18F fluoride.
This solution is then used for rapid synthesis of a labeled molecule, often with the fluorine atom replacing a hydroxyl group.
Large amounts of oxygen-18 enriched water are used in positron emission tomography centers, for on-site production of 18F-labeled fludeoxyglucose (FDG).