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Investor Presentaiton

Doses to workers The average effective dose to the more than 20,000 emergency workers involved in mitigation and other activities at the FDNPS site from March 2011 to the end of March 2012 was about 13 mSv. About 36 per cent received an effective dose of more than 10 mSv, while 0.8 per cent (174 workers) were assessed to have received more than 100 mSv in this period. Annual effective doses have been considerably lower since April 2012, with average annual effective doses declining from about 6 mSv in the year to the end of March 2013 to about 2.5 mSv in the year to the end of March 2020. No worker has received an annual effective dose of more than 50 mSv since April 2013. Absorbed doses to the thyroid of a small number of emergency workers who received the highest doses have been reassessed, in particular using individual-specific measurements of thyroid size, and this has led to changes in the assessed doses to the thyroid of these individuals. Health effects Since the UNSCEAR 2013 Report, no adverse health effects among Fukushima residents have been documented that could be directly attributed to radiation exposure from the accident. Exposure to radiation could lead to an increased incidence of disease in the exposed population; however for example, with cancer, it is not generally possible to distinguish by observation or testing whether or not the disease of a specific patient has been caused by the radiation exposure. The Committee has therefore assessed the risks resulting from radiation exposure following the accident by estimating whether any increased incidence of a particular disease, calculated theoretically from the estimated doses, would be detectable compared to the normal statistical variability in the baseline incidence of the disease in that population. The Committee's conclusion is that its revised estimates of dose are such that future radiation- associated health effects are unlikely to be detectable. Following the accident, the greatest concern was whether the exposure to radiation resulting from the accident would lead to an increase in rates of thyroid cancer in the population in Japan. Although a substantial number of thyroid cancers have been detected among exposed children, the Committee believes that, on the balance of available evidence, the (relative to expected) large increase in thyroid cancers is the result of ultrasensitive screening procedures that have revealed the prevalence of thyroid abnormalities in the population not previously recognized, and is not a result of radiation exposure. The Committee also concluded that no detectable excesses of other types of cancer that are sensitive to radiation, such as leukaemia or breast cancer, were likely because of the generally low levels of radiation exposure in the Fukushima Prefecture population. There has been no credible evidence of excess birth defects, stillbirths, premature births or low birthweights related to radiation exposure. Increases in the incidence of cardiovascular and metabolic conditions have been observed among those evacuated following the accident but are probably associated with concomitant social and lifestyle changes and not attributable to radiation exposure. Excess psychological distress also occurred in the aftermath of the combined earthquake, tsunami and FDNPS accident. However, the report does not address other health consequences, such as mental health or financial impacts, which are beyond the Committee's mandate. Thyroid (ultrasound) screening No adverse health effects among Fukushima residents have been documented that could be directly attributed to radiation exposure from the accident. In particular, an increase in the incidence of cancers is also unlikely to be detectable in workers for leukaemia, total solid cancers or thyroid cancer. The Committee has insufficient information to reach an informed judgement on the risk of cataracts. On the balance of available evidence, the large increase, relative to that expected, in the number of thyroid cancers detected among exposed children is the result of intensive thyroid screening, not of radiation exposure.
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