The 69th session of the Scientific Committee took place from 9 to 13 May 2022 in Vienna with hybrid working arrangements, attended by 187 participants from 31 State members of the Committee and 13 international organizations. The Scientific Committee discussed matters arising from the General Assembly resolution A/RES/76/75.

The Scientific Committee elected a new bureau for the 69^th and 70^th sessions and discussed the following technical documents:

• Second primary cancer after radiotherapy;
• Epidemiological studies of radiation and cancer;
• Evaluation of public exposure to ionizing radiation from natural and other sources.

Furthermore, it considered the progress report on the evaluation of diseases of the circulatory system from radiation exposure.

The Scientific Committee also discussed the Implementation of its (a) Future Programme of Work (2020-2024), and (b) Public information and outreach strategy for 2020-2024. It adopted a new data collection strategy to improve collection, analysis and dissemination of data on radiation exposure, selected six new topics for its future programme of work for further evaluation and discussion at the 70^th session and revised its governing principles.

The 68th session took place as an online meeting from 21 to 25 June 2021, attended by over 220 participants from 27 State members of UNSCEAR, 4 observer countries and 12 international organizations. The Scientific Committee celebrated this year its 65th anniversary and discussed matters arising from General Assembly resolution A/RES/75/91.

The Scientific Committee approved its scientific annex entitled "Evaluation of occupational exposure to ionizing radiation". Furthermore, it agreed to initiate a new evaluation on Diseases of the circulatory system from radiation exposure and considered progress reports on the following topics:

• Second primary cancer after radiotherapy;
• Epidemiological studies of radiation and cancer;
• Evaluation of public exposure to ionizing radiation from natural and other sources.

The Scientific Committee also discussed the Implementation of its (a) Future Programme of Work (2020-2024), (b) Public information and outreach strategy for 2020-2024, and (c) Strategy to improve collection, analysis and dissemination of data on radiation exposure. It decided to extend the tenure of the current Bureau until its 69th session in 2022.

The 67th session of UNSCEAR took place as an online meeting from 2 to 6 November 2020, attended by over 200 participants from 27 State members of UNSCEAR, 4 observer countries and 11 international organizations.

The Scientific Committee discussed matters arising from General Assembly resolution 74/81.

The Scientific Committee approved its Future Programme of Work (2020-2024) and the following three scientific annexes:

• Evaluation of medical exposure to ionizing radiation;
• Levels and effects of radiation exposure due to the accident at the Fukushima Daiichi nuclear power station: implications of information published since the UNSCEAR 2013 Report;
• Biological mechanisms relevant for the influence of cancer risks from low-dose and low dose rate radiation.

Furthermore, the Scientific Committee held technical discussions and considered progress reports on the following topics:

• Evaluation of occupational exposure to ionizing radiation;
• Second primary cancer after radiotherapy;
• Epidemiological studies of radiation and cancer;
• Evaluation of public exposure to ionizing radiation from natural and man-made sources.

The Scientific Committee also discussed the Implementation of public information and outreach strategy for 2020-2024 and the Implementation of the Committee's strategy to improve collection, analysis and dissemination of data on radiation exposure.

The Scientific Committee elected Anssi Auvinen (Finland) as Rapporteur for the session.

The 66th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 10 to 14 June 2019. The Committee elected Gillian Hirth (Australia) as Chair, Jing Chen (Canada), Anna Friedl (Germany) and Jin Kyung Lee (Republic of Korea) as Vice-Chairs, and Ingemar Lund (Sweden) as Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 73/261, including its future programme of work (2020-2024).

The Committee approved two documents:

• Evaluation of selected health effects and inference of risk due to radiation exposure;
• Lung cancer from exposure to radon.

Furthermore, the Committee held technical discussions on four documents:

• Evaluation of medical exposures to ionizing radiation;
• Evaluation of occupational exposures to ionizing radiation;
• Biological mechanisms relevant for influence of cancer risks from low-dose radiation,
• Levels and effects of radiation exposure due to the accident at the Fukushima Daiichi nuclear power station: implications of information published since the 2013 UNSCEAR report.

The Committee also approved the Public Information and Outreach Strategy for 2020-2024 prepared by the secretariat and considered progress reports on the following topics:

• Second primary cancer after radiotherapy;
• Epidemiological studies of radiation and cancer;
• Implementation of the Committee's strategy to improve collection, analysis and dissemination of data on radiation exposure. For this, the Committee decided to establish an ad hoc working group to support its work on radiological sources and levels of exposure.

The 65th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 11 to 14 June 2018. Hans Vanmarcke (Belgium) was Chair, Patsy Thompson (Canada), Peter Jacob (Germany) and Michael Waligórski (Poland) were Vice-Chairs, and Gillian Hirth (Australia) was Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 72/76 including its future programme of work. The Committee held technical discussions on five documents prepared by the secretariat:

• Selected evaluations of health effects and of risk inference due to radiation exposure;
• Evaluation of medical exposures to ionizing radiation;
• Evaluation of occupational exposures to ionizing radiation;
• Lung cancer from exposure to radon and to penetrating radiation; and
• Biological mechanisms influencing health effects from low-dose radiation exposure.

Furthermore, the Committee agreed a project plan for updating of the UNSCEAR 2013 Report with the intention to produce a new Report by the tenth anniversary of the accident, in 2021. Further, the Committee established an ad hoc working group to assist in developing the Committee's future programme of work on the effects of radiation exposure and the biological mechanisms for the period 2020-2024.

The 64th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 29 May to 2 June 2017. Hans Vanmarcke (Belgium) was Chair, Patsy Thompson (Canada), Peter Jacob (Germany) and Michael Waligórski (Poland) were Vice-Chairs, and Gillian Hirth (Australia) was Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 71/89 including its future programme of work. The Committee held technical discussions on six documents prepared by the secretariat:

• Quality criteria for the Committee's reviews of epidemiological studies
• Epidemiological studies of cancer risk due to low dose-rate radiation from environmental sources, including the scientific view of the Committee on the dose and dose rate effectiveness factor
• Selected evaluations of health effects and of risk inference due to radiation exposure
• Developments since the 2013 UNSCEAR Report on the levels and effects of radiation exposure due to the nuclear accident following the great east-Japan earthquake and tsunami: review of 2016 scientific literature, including an evaluation of thyroid cancer data in regions affected by the Chernobyl accident
• Exposures of patients to ionizing radiation
• Exposures of workers to ionizing radiation

Furthermore, the Committee considered progress reports on the following topics:

• Lung cancer from exposure to radon and to penetrating radiation
• Biological mechanisms influencing health effects from low-dose radiation exposure
• Collection, analysis and dissemination of data on radiation exposures, in particular of the public from natural and artificial sources
• Implementation of the Public Information and Outreach Strategy (2014-2019)

The 63rd session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 27 June to 1 July 2016. Yoshiharu Yonekura (Japan) was Chair, John Hunt (Brazil), Peter Jacob (Germany) and Hans Vanmarcke (Belgium) were Vice-Chairs, and Michael Waligórski (Poland) was Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 70/81 including its future programme of work. The Committee held technical discussions on four documents prepared by the secretariat:

• Methodology for estimating human exposures due to radioactive discharges
• Radiation exposures from electricity generation
• Biological effects of selected internal emitters (tritium and uranium)
• Developments since the 2013 UNSCEAR Report on the levels and effects of radiation exposure due to the nuclear accident following the great east-Japan earthquake and tsunami

Furthermore, the Committee considered progress reports on the following topics:

• Cancer epidemiology of exposures at low dose-rates due to environmental radiation, including quality criteria for the Committee's reviews of epidemiological studies
• Collection, analysis and dissemination of data on radiation exposures, in particular on medical and occupational exposures
• Implementation of the Public Information and Outreach Strategy (2014-2019)
• Selected evaluations of health effects and risk inference from radiation exposure

The Committee also elected officers for its sixty-fourth and sixty-fifth sessions.

The 62nd session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 1 to 5 June 2015. Yoshiharu Yonekura (Japan) was Chair, John Hunt (Brazil), Peter Jacob (Germany) and Hans Vanmarcke (Belgium) were Vice-Chairs, and Michael Waligórski (Poland) was Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 69/84 including its future programme of work. The Committee held technical discussions on three documents prepared by the secretariat:

• Methodology for estimating human exposures due to radioactive discharges
• Radiation exposures from electricity generation
• Biological effects of selected internal emitters (tritium and uranium)

Furthermore, the Committee considered progress reports on the following topics:

• Cancer epidemiology of exposures at low dose-rates due to environmental radiation
• Collection, analysis and dissemination of data on radiation exposures, in particular on medical and occupational exposures
• Developments since the 2013 UNSCEAR Report on the levels and effects of radiation exposure due to the nuclear accident following the great east-Japan earthquake and tsunami
• Implementation of the Public Information and Outreach Strategy (2014-2019)

The 61st session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 21 to 25 July 2014. Carl-Magnus Larsson (Australia) was Chair, Yoshiharu Yonekura (Japan) Vice-Chair and Michael Waligórski (Poland) Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 68/73 including its programme of work. The Committee held technical discussions on three documents prepared by the secretariat:

• Methodology for estimating human exposures due to radioactive discharges
• Radiation exposures from electricity generation
• Biological effects of selected internal emitters (tritium and uranium)

Furthermore, the Committee considered progress reports on the following topics:

• Epidemiology of low-dose-rate exposures of the public to natural and artificial environmental sources of radiation
• Development of an evaluation of medical exposures
• Outreach activities

The 60th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 27 to 31 May 2013. Carl-Magnus Larsson (Australia) was Chair, Emil Bédi (Slovakia) Vice-Chair and Yoshiharu Yonekura (Japan) Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 67/112 including its programme of work and strategic plan (2014-2019). The Committee held technical discussions on two documents prepared by the secretariat:

• Levels and effects of radiation exposure due to the nuclear accident after the 2011 great east-Japan earthquake and tsunami
• Effects of radiation exposure on children

Furthermore, the Committee considered progress reports on the following topics:

• Methodology for estimating human exposures due to radioactive discharges
• Radiation exposures from electricity generation
• Biological effects of selected internal emitters (tritium and uranium)
• Epidemiology of low-dose-rate exposures of the public to natural and artificial environmental sources of radiation
• Development of an evaluation of medical exposures
• Outreach activities

The 59th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 21 to 25 May 2012. Wolfgang Weiss (Germany) was Chairman, Carl-Magnus Larsson (Australia) Vice-Chairman and Leif Moberg (Sweden) Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 66/70 including its programme of work and improving collection, analysis and dissemination of exposure data. The Committee held technical discussions on nine documents prepared by the secretariat:

• Ability to attribute risks and effects to radiation exposure
• Uncertainties in risk estimates for cancer due to exposure to ionizing radiation
• Radiation exposures from electricity generation
• Methodology for estimating human exposures due to radioactive discharges
• Biological effects of selected internal emitters (tritium and uranium)
• Levels and effects of radiation exposure due to the nuclear accident after the 2011 great east-Japan earthquake and tsunami
• Effects of radiation exposure on children
• Epidemiology of low-dose-rate exposures of the public to natural and artificial environmental sources of radiation
• Mechanisms of radiation actions at low doses

The Committee has also elected officers for its sixtieth and sixty-first sessions.

The 58th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria, from 23 to 27 May 2011. Wolfgang Weiss (Germany) was Chairman, Carl-Magnus Larsson (Australia) Vice-Chairman and Mohamed A. Gomaa (Egypt) Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 65/96. It also considered its future programme of work (including proposals on assessing the radiological impact of the the nuclear power plant accident following the great east-Japan earthquake and tsunami of March 2011, radiation effects on children, and epidemiology of low-dose rates of radiation exposure) and improving collection, analysis and dissemination of exposure data. The Committee held technical discussions on five documents prepared by the secretariat:

• Ability to attribute risks and effects to radiation exposure
• Uncertainties in risk estimates for cancer due to radiation exposure
• Radiation exposures from electricity generation
• Methodology for estimating human exposures due to discharges
• Biological effects of selected internal emitters

The 57th session of UNSCEAR, originally scheduled to take place in 2009, was postponed from 2009 to 2010 owing to unforeseen circumstances. Owing to flight disruptions caused by ash from the volcanic eruption in Iceland, the session had to be postponed a second time from April to August 2010. It took place at the Vienna International Centre, Vienna, Austria from 16 to 20 August 2010. Norman Gentner (Canada) was Chairman, Wolfgang Weiss (Germany) Vice-Chairman and Mohamed A. Gomaa (Egypt) Rapporteur for the session.

The Committee discussed matters arising from General Assembly resolution 63/89 and resolution 64/85, including its programme of work, and members' support of the Committee's work. The Committee held technical discussions on six documents prepared by the secretariat:

• Assessment of levels of radiation from electrical energy production
• Uncertainty in radiation risk estimation
• Attributability of health effects to radiation exposure
• Methodology for estimating exposures due to discharges
• Summary of radiation effects
• Improving data collection, analysis and dissemination

The Committee has also elected officers for its fifty-eighth and fifty-ninth sessions.

The 56th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria from 10 to 18 July 2008. Norman Gentner (Canada) was Chairman, Wolfgang Weiss (Germany) was Vice-Chairman and Mohamed A. Gomaa (Egypt) was Rapporteur.

The Committee discussed matters arising from General Assembly resolution 62/100 of 17 December 2007, including development of a strategic plan and future programme of work. It also held technical discussions on five documents:

• Medical radiation exposures
• Exposures of workers and the public from various sources of radiation
• Exposures from radiation accidents
• Effects of ionizing radiation on non-human biota
• Health effects due to radiation from the Chernobyl accident

The Committee approved a report to the 63rd General Assembly ( A/63/46), which describes the deliberations of the Committee at its fifty-sixth session, the strategic plan and programme of work, and a scientific report discussing sources of radiation exposure, the Chernobyl accident and effects on non-human biota.

The Committee also expressed its views on membership, staffing and financing, which were appended to a report of the Secretary-General on Financial and administrative implications of increased membership of the United Nations Scientific Committee on the Effects of Atomic Radiation, staffing of the professional secretariat of the Scientific Committee and methods to ensure sufficient, assured and predictable funding ( A/63/478).

The 55th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria from 21 to 25 May 2007. Peter Burns (Australia) was Chairman, Norman Gentner (Canada) was Vice-Chairman, and Wolfgang Weiss (Germany) was Rapporteur.

The Committee discussed, provided feedback and comment on drafts of six documents:

• Medical radiation exposures
• Exposures of workers and the public from various sources of radiation
• Exposures from radiation accidents
• Effects of ionizing radiation on non-human biota
• Health effects due to radiation from the Chernobyl accident
• Sources of radiation and effects of exposure

It also discussed matters relating to its annual progress report to the General Assembly (A/62/46), development of a future strategy and programme of work, and financial, management, procedural and other matters.

The 54th session of UNSCEAR took place at the Vienna International Centre, Vienna, Austria from 29 May to 2 June 2006. Peter Burns of Australia was Chairman. Norman Gentner of Canada was Vice-Chairman. Christian Streffer of Germany was Rapporteur.

The Committee approved five documents for publication on:

• Epidemiological studies of radiation and cancer
• Epidemiological evaluation and dose response of diseases other than cancer
• Non-targeted and delayed effects of exposure to ionizing radiation
• Effects of ionizing radiation on the immune system
• Sources-to-effects assessment for radon in homes and workplaces

It provided feedback and comment on drafts of other documents submitted by the Secretariat:

• Medical radiation exposures
• Exposures of workers and the public from various sources of radiation
• Exposures from radiation accidents
• Effects of ionizing radiation on non-human biota

It also discussed matters relating to its annual progress report to the General Assembly ( A/61/46 + Corr.1), its work on assessing the consequences of the Chernobyl accident, and financial, management, procedural and other matters.

During the session, the mayor of Vienna hosted a reception for invited high-level dignitaries, diplomats and scientists to commemorate the fiftieth anniversary of UNSCEAR.