He is a descendant of Kakure Kirishitans in Urakami[2] (present Nagasaki City) who kept their faith clandestinely more than 200 years under severe persecution from the Tokugawa Shogunate.

[5] According to an interview by the Asahi Shimbun, his respect for Dr. Paul Takashi Nagai (the author of The Bell of Nagasaki) encouraged him to become a medical doctor.

In The Journal of Japan Physicians Association, he writes: “Mainly for the people less than twenty-years-old, if they are exposed to excessive radiation between 10 and 100mSV, the risk of carcinogenesis is undeniable”.

[14] The other report written with other scientists points out, “the lowest doses of X-rays for which reasonably reliable evidence of increased cancer risk exists range from 10 to 50mGy”.

[17] Later, In the name of Bishop Marcelious Daiji Tani, leaflets based on the lecture were printed in six languages and distributed in the diocese and shelters.

[18][19][20] When he was installed as a vice-president of Fukushima Medical University, the diocesan newsletter called Yoki Otozure (Good Visit) in the Nagasaki Archdiocese reported this event.

[23] On May 24, 2011, Yamashita was invited by the Komeito Party's election campaign office of Koriyama City, Fukuhsima Prefecture and lectured there.

[27] On March 19, 2011, Yamashita visited the prefectural government's disaster headquarters and said, "Information about radiation risks has not been correctly communicated.

[29] However, in the affected areas like Iitate, Soma and Minami-Soma, high radiation doses required people to take iodine pills for thyroid blockage by the standard of Japan (100mSV)[30] and WTO (10mSV) was widely detected according to the SPEEDI map released to the public on March 24, 2011.

[31] In April, Yamashita become a member of the committee for disputes of nuclear liability by Ministry of Education, Culture, Sports, Science and Technology.

[36] Takashi Hirose, writer and anti-nuke activist with Shojiro Akashi, made accusations of criminal negligence against executives of TEPCO and affiliated people including Yamashita in July 2011.

[40] On March 11, 2012, the one-year anniversary of the 2011 Tōhoku earthquake and tsunami, Yamashita spoke to the students, faculty and staff at Khalifa University, UAE.

[42] In February 2013, Yamashita informed Nature by email that he would quit his post as the head of Fukushima prefecture's massive survey at the end of March.