They added that the predicted risks for developing cancer for the general population living inside and outside Japan are relatively low.
On March 11, 2011, a magnitude 9 earthquake was followed by a tsunami that struck the Fukushima I Power Plant, resulting in a series of equipment failures, nuclear meltdowns, and the release of radioactive materials. It was the largest nuclear disaster since the Chernobyl disaster of 1986. The two disasters were the only ones ever to measure Level 7 on the International Nuclear Event Scale. Hundreds of thousands of people had to flee their homes to avoid radiation poisoning.
The World Health Organization (WHO) identified that the risk of certain cancers among people living in the Fukushima Prefecture has gone up following the disaster. It said that long term monitoring and health screening of people in the area is essential.
According to Dr Maria Neira, WHO Director for Public Health and Environment:
"The primary concern identified in this report is related to specific cancer risks linked to particular locations and demographic factors. A breakdown of data, based on age, gender and proximity to the nuclear plant, does show a higher cancer risk for those located in the most contaminated parts. Outside these parts - even in locations inside Fukushima Prefecture - no observable increases in cancer incidence are expected."
They identified that in the most contaminated locations:
- Females are at a 4% increased risk of all solid cancers
- Females have a 6% higher risk of breast cancer
- Females have a 70% increased risk of thyroid cancer
- Males have a 7% increased risk of leukemia.
One-third of the emergency workers inside the Fukushima NPP are at an increased risk of cancer because of elevated radiation exposure. A group of Japanese experts wrote in The Lancet that in order to prepare for any future stem cell transplants as a result of radiation exposure, the workers should store their own blood - which could be useful for treating leukemia.
They note that the radiation doses from the disaster are not expected to cause an increased rate of stillbirths or miscarriages.
Dr Maria Neira, WHO Director for Public Health and Environment, said:
"The WHO report underlines the need for long-term health monitoring of those who are at high risk, along with the provision of necessary medical follow-up and support services.This will remain an important element in the public health response to the disaster for decades."
The experts mention that the psychosocial impact of the Fukushima disaster also has an effect on the health and well being of the population in the area and should not be ignored.
Dr Angelika Tritscher, Acting Director for WHO's Food Safety and Zoonosis Department, said:
"In addition to strengthening medical support and services, continued environmental monitoring, in particular of food and water supplies, backed by the enforcement of existing regulations, is required to reduce potential radiation exposure in the future."
The analysis is the first of its kind to study the health effects due to radiation exposure following the Fukushima Power Plant disaster.
Written by Joseph Nordqvist