 Estimates of health effects are a subject of some controversy, see Effects of the Chernobyl disaster.In 1998, average caesium-137 doses from the accident (estimated at 1-2mSv per year) did not exceed those from other sources of exposure.Current effective caesium-137 dose rates as of 2019 are 200-250 nSv/h, or roughly 1.7-2.2 mSv per year,
which is comparable to the worldwide average background radiation from natural sources.