In March 2011 a series of cascading disasters hit the northeast coast of Japan — earthquake and tsunami, then a nuclear emergency. While the first two created widespread devastation and untold suffering, the third is likely to have the longest-felt effects. After the debris has been removed, towns rebuilt and the economy stabilized, evidence from Chernobyl indicates that health concerns will persist for nearby residents for decades to come.

A 2011 study published in Environmental Health Perspectives, “I-131 Dose-Response for Incident Thyroid Cancers in Ukraine Related to the Chernobyl Accident,” followed 12,500 participants (who were under 18 and had known thyroid radioactivity levels at the time of the Chernobyl accident) and screened them for thyroid cancer up to four times between 1998 and 2008.

Results of the study include:

• Across the sample population there exists an increased risk of thyroid cancer 20 years after the initial exposure. This risk was not uniform for the whole sample and was most varied conditional on geographical distance from the plant at the time of exposure.
• The level of increased risk of thyroid cancer was quantified at on average 1.91 times higher for every additional gray of radiation. (A gray = the absorption of one joule of ionizing radiation per one kilogram of tissue).
• There is no evidence indicating that this increased cancer risk for those who lived in the area at the time of the accident is decreasing at all over time.

Previous studies of atomic bomb survivors have shown that even 30 years after the initial radiation occurs increased cancer risks exist and do not significantly decline until after this point. The authors of this Chernobyl-focused study recognize the need to continue following up with their subjects in order to accurately understand the long-term effects of future nuclear accidents.

Tags: cancer, disasters, nuclear power, nuclear waste, technology