**Preface to "Assessment of Environmental Radioactivity and Radiation for Human Health Risk"**

In 2010, the Institute of Radiation Emergency Medicine (IREM) was established as a strategic research institute at Hirosaki University, Japan. Subsequently, the Great East Japan Earthquake occurred on 11 March 2011, and consequently a nuclear accident occurred at Tokyo Electric Power's Fukushima Daiichi Nuclear Power Plant. We played an important role in the response to the disaster and transmitted a wide range of academic information. This achievement has been highly rated, not only in Japan but also internationally. In parallel, we have started a human resources development project for the Nuclear Regulation Authority and other projects that aim to create a hub institution for domestic utilization and collaborative research.

This Special Issue book of the *International Journal of Environmental Research and Public Health*, titled "Assessment of Environmental Radioactivity and Radiation for Human Health Risk", is the one of IREM's accomplishments and is published to commemorate the 10th anniversary of the Institute of Radiation Emergency Medicine. This book provides a collection of high-quality research papers in radiation-related fields, such as environmental radioactivity, environmental radiation, measurement data, methodology, monitoring, and risk assessment. Finally, we thank all the reviewers, editors and authors for their important anonymous contributions under a very strict time constraint, and we would like to acknowledge all of the authors for their excellent research.

> **Shinji Tokonami, Ikuo Kashiwakura** *Editors*

International Journal of *Environmental Research and Public Health*
