Masumi Marumoto, Senior Researcher｜About NIMD｜National Institute for Minamata Disease

Ensuring appropriate management of the pathological samples related to Minamata disease and making use of them to deliver information Pathological tissue samples from Minamata disease autopsy cases, as well as documentations, are extremely valuable materials that humanity could never again get hold of, unlike in cases of other disorders and conditions. It is, however, difficult to maintain pathological tissue samples permanently, due to the process of discoloration that takes place over years. For that reason, we are working to have them digitized for permanent preservation. In addition to taking these steps, we also strive to foster an understanding of pathology of Minamata disease by making public on the Internet the digitized pathological samples as educational case examples for use by students and researchers who study pathology.

Science and technology research-related outreach activities for elementary and junior high school students. We run a "lecture delivery" program that caters to elementary and junior high school students. Our lecture topics vary, such as a talk themed on mercury or a talk on science, and the subject and length of a given lecture are coordinated to cater to the age and needs of participating students.

Research theme - Areas of work

Research theme

Biological defense in large marine life, etc. against methylmercury toxicity by forming a conjugate with selenium

Main research achievements

Open

Papers published

2022

Marumoto M, Sakamoto M, Nakamura M, Marumoto K, Tsuruta S. Organ-specific accumulation of selenium and mercury in Indo-Pacific bottlenose dolphins (Tursiops aduncus).
Acta Vet Scand. 2022 Jan 27;64(1):1. doi: 10.1186/s13028-021-00607-w. Peer-reviewed.
Sakamoto M, Haraguchi K, Tatsuta N, Marumoto M, Yamamoto M, Nakamura M. Breast milk contribution to tissue mercury levels in rat pups examined by cross-fostering at birth. Environ Res. 2022 May 15;208:112772. Peer-reviewed.

2021

Marumoto M, Marumoto K, Noda K.　Availability Evaluation for a Simple Personal Mercury Monitor Using Rats Exposed to Mercury Vapor. Kankyo Kagaku Kaishi (Environmental Science. 2021, Vol. 34, No. 6, p. 247-255. Peer-reviewed.
Marumoto M, Sakamoto M, Marumoto K, Tsuruta S, Komohara Y. Mercury and selenium localization in the cerebrum, cerebellum, liver, and kidney of a Minamata disease case Acta Histochemica et Cytochemica Peer-reviewed.

2020

Marumoto K, Noda K, Pereira JPG, DE Oliveira Lima M, DE Jesus IM, Marumoto M, Akagi H. Application of the quartz crystal microbalance method for measuring mercury in the air of working environments involved to artisanal and small-scale gold mining (ASGM). Anal Sci. 2020 Aug 21. doi: 10.2116/analsci.20P178. Online ahead of print. PMID: 32830160 Peer-reviewed.
O'Donoghue JL, Watson GE, Brewer R, Zareba G, Eto K, Takahashi H, Marumoto M, Love T, Harrington D, Myers GJ. Neuropathology associated with exposure to different concentrations and species of mercury: A review of autopsy cases and the literature. Neurotoxicology. 2020 May;78:88-98. doi: 10.1016/j.neuro.2020.02.011. Epub 2020 Feb 22. Peer-reviewed.
Sakamoto M, Itai T, Marumoto K, Marumoto M, Kodamatani H, Tomiyasu T, Nagasaka H, Mori K, Poulain AJ, Domingo JL, Horvat M, Matsuyama A. Mercury speciation in preserved historical sludge: Potential risk from sludge contained within reclaimed land of Minamata Bay, Japan (2020) Environmental Research Peer-reviewed.

2015

Sakamoto M, Itai T, Yasutake A, Iwasaki T, Yasunaga G, Fujise Y, Nakamura M, Murata K, Chan HM, Domingo JL, Marumoto M. Mercury speciation and selenium in toothed-whale muscles. Environmental Research. 2015 (143):55-61. Peer-reviewed.

2012

Bourdineaud JP, Marumoto M, Yasutake A, Fujimura M. Dietary mercury exposure resulted in behavioral differences in mice contaminated with fish-associated methylmercury compared to methylmercury chloride added to diet.J Biomed Biotechnol. 2012 Article ID:681016. Peer-reviewed.

2011

Nakamura M, Yasutake A, Fujimura M, Hachiya N, Marumoto M. Effect of methylmercury administration on choroid plexus function in rats.Arch Toxicol. 2011 Aug;85(8):911-8. Peer-reviewed.
Mori N, Yasutake A, Marumoto M, Hirayama K. Methylmercury inhibits electron transport chain activity and induces cytochrome c release in cerebellum mitochondria. J Toxicol Sci. 2011 Jun;36(3):253-9. Peer-reviewed.
Bourdineaud JP, Fujimura M, Laclau M, Sawada M, Yasutake A. Deleterious effects in mice of fish-associated methylmercury contained in a diet mimicking the Western populations' average fish consumption. Environ Int. 2011 Feb;37(2):303-13. Peer-reviewed.

2010

Eto K, Marumoto M, Takeya M. The pathology of methylmercury poisoning (Minamata disease). Neuropathology. 2010 30:471-479. Peer-reviewed.
Yasutake A, Marumoto M, Yoshida M. Neurotoxic action of inorganic mercury injected in the intraventricular space of mouse cerebrum. J Toxicol Sci. 2010 Oct;35(5):767-71. Peer-reviewed.

2009

Fujimura M, Usuki F, Sawada M, Takashima A. Methylmercury induces neuropathological changes with tau hyperphosphorylation mainly through the activation of the c-jun-N-terminal kinase pathway in the cerebral cortex, but not in the hippocampus of the mouse brain. Neurotoxicology. 2009 Nov;30(6):1000-7. Peer-reviewed.
Fujimura M, Usuki F, Sawada M, Rostene W, Godefroy D, Takashima A. Methylmercury exposure downregulates the expression of Racl and leads to neuritic degeneration and ultimately apoptosis in cerebrocortical neurons. Neurotoxicology. 2009 Jan;30(1):16-22. Peer-reviewed.

2008

Bourdineaud JP, Bellance N, Bénard G, Brèthes D, Fujimura M, Gonzalez P, Marighetto A, Maury-Brachet R, Mormède C, Pédron V, Philippin JN, Rossignol R, Rostène W, Sawada M, Laclau M. Feeding mice with diets containing mercury-contaminated fish flesh from French Guiana: a model for the mercurial intoxication of the Wayana Amerindians. Environ Health. 2008 Oct 29;7:53. Peer-reviewed.

2007

Eto M, Yasutake A, Sawada M, Tokunaga H, Korogi Y. Pathology of Minamata disease: Methylmercury toxicity. Byori To Rinsho (Pathology and Clinical Medicine). 2007, 25(8): 776-779. Peer-reviewed.
Eto M, Takahashi H, Kakita A, Tokunaga H, Yasutake A, Nakano A,Sawada M, Kinjo Y. A pathological and biochemical study on 30 autopsy cases related to Niigata Minamata disease. Nihon Eiseigaku Zasshi (Japanese Journal of Hygiene). 2007, 70-88.

2006

Imagawa T, Yamamoto E, Sawada M, Okamoto M, Uehara M. Expression of lactate dehydrogenase-A and -B messenger ribonucleic acids in chick glycogen body.Poult Sci. 2006 Jul;85(7):1232-8. Peer-reviewed.
Yoshida M, Watanabe C, Kishimoto M, Yasutake A, Satoh M, Sawada M, Akama Y.Behavioral changes in metallothionein-null mice after the cessation of long-term, low-level exposure to mercury vapor. Toxicol Lett. 2006 Mar 1;161(3):210-8. Peer-reviewed.

2003

Tomioka Y, Sawada M, Ochiai K, Umemura T. Neospora caninum antigens recognized by mouse IgG at different stages of infection including recrudescence. J Vet Med Sci. 2003 Jun;65(6):745-7. Peer-reviewed.

2000

Park CH, Sawada M, Morita T, Shimada A, Ochiai K, Umemura T. Neospora caninum infected the alimentary tract of nude mice and was transmitted to other mice by intraperitoneal inoculation with the intestinal contents. J Vet Med Sci. 2000 May;62(5):525-7. Peer-reviewed.
Sawada M, Kondo H, Tomioka Y, Park C, Morita T, Shimada A, Umemura T.Isolation of Neospora caninum from the brain of a naturally infected adult dairy cow.Vet Parasitol. 2000 Jun 27;90(3):247-52. Peer-reviewed.

1998

Yamane I, Shibahara T, Kokuho T, Shimura K, Hamaoka T, Haritani M, Conrad PA, Park CH, Sawada M, Umemura T. An improved isolation technique for bovine Neospora species. J Vet Diagn Invest. 1998 Oct;10(4):364-8. Peer-reviewed.
Sawada M, Park CH, Kondo H, Morita T, Shimada A, Yamane I, Umemura T.Serological survey of antibody to Neospora caninum in Japanese dogs. J Vet Med Sci. 1998 Jul;60(7):853-4. Peer-reviewed.

1997

Sawada M, Park CH, Morita T, Shimada A, Umemura T, Haritani M.Pathological findings of nude mice inoculated with bovine Neospora. J Vet Med Sci. 1997 Oct;59(10):947-8. Peer-reviewed.

Involvement in the development of informative brochures for the general public

2022

Masumi Marumoto, Nobutaka Arai, Tomoko Yagi, Brain's mechanism and Minamata disease: Occipital lobe. Issued FY2022. 10 pages.

2021

Masumi Marumoto, Nobutaka Arai, Tomoko Yagi, Brain's mechanism and Minamata disease: Cerebellum. Issued FY2021. 10 pages.

Presentations at academic conferences (in Japan)

2022

Marumoto M, Sakamoto M, Marumoto K. Relationship between mercury and selenium in organs of Carcharhinus albimarginatus, 2022 Conference of the Society of Environmental Science. Online, 2022
Marumoto M, Marumoto K, Sakamoto M, Nakamura M, Tsuruta S. Histological distribution of mercury and selenium in the brain of Tursiops truncatus. 32nd Conference of the Cetology Study Group of Japan. 2022

2021

Marumoto M, Marumoto K, Sakamoto M, Tsuruta S. Total mercury and selenium concentration levels in organs of Phocoenoides dalli. 32nd Conference of the Japan Society for Biomedical Research on Trace Elements. Online, 2021

2019

Marumoto M, Marumoto K, Noda K, Akagi H. Development and application of an airborne mercury measuring instrument using the quartz crystal microbalance method. 2019 Conference of the Society of Environmental Science. Nagoya, 2019.
Marumoto M, Marumoto K, Noda K. Availability Evaluation for a Simple Personal Mercury Monitor Using Rats Exposed to Mercury Vapor. 2019 Conference of the Society of Environmental Science. Nagoya, 2019.
Masumi Marumoto, Mineshi Sakamoto, Kohji Marumoto and Shozo Tsuruta: Localization of mercury and selenium in the liver and kidney of the bottlenose dolphin. 30th Anual Meeting of Cetology Study Group of Japan, Tokyo, 2019.6.

2015

Marumoto M, Sakamoto M, Marumoto K, Tsuruta S, Eto M, Takeya M. Localization of mercury and selenium in the cerebrum, cerebellum, liver and kidney in acute episodes of Minamata disease. 26th Conference of the Japan Society for Biomedical Research on Trace Elements. Sapporo, 2015.

Presentations at academic conferences (overseas)

2007

Sawada M, Fujimura M, Yasutake A: Methylmercury exposure induces hyperactivity and neuronal loss in the caudate putamen in mice. Twenty-fourth International Neurotoxicology Conference. San Antonio, Texas, USA, 2007. 11.

2006

Sawada M, Fujimura M,Yasutake A, Eto K: Trigeminal nerve pathology and its pathogenesis in methylmercury-intoxicated rats. 8th International Conference on Mercury as a Global Pollutant, Madison, USA, 2006. 8.

2004

Sawada M, Sunagawa Y, Morita T, Shimada A, Yoshida M. Effects of mercury vapor exposure on murine thymus. 7th International Conference of Mercury as a Global Pollutant 2004

Lecture delivery, etc.

Date	School name	Grade	Main lecture theme	Number of students
December 7, 2019	Minamata Dai-Ni Elementary School	Grade 6	Mercury comes in various forms	59
January 14, 2020	Minamata Dai-Ni Elementary School	Grade 5	Methylmercury is in my body as well	63
September 16	Minamata High School	First year	Can you describe mercury to someone?	127
October 10	Minamata Dai-Ni Elementary School	Second year	Let's blow bubbles	32
October 24	Minamata Dai-Ichi Elementary School	Grades 4, 5 and 6	What researchers do (Issho Festival)	27
November 14	Minamata High School	Second year	KSH poster presentation	3
November 28	Minamata Environmental Academia	Elementary school students	Let's look at real working cells	4
June 23, 2021	Minamata Dai-Ni Elementary School	Grade 5	Mercury used since ancient times	34
October 24	Minamata Dai-Ichi Elementary School	Grades 4, 5 and 6	What researchers do: Let's extract DNA (Issho Festival)	36
February 24, 2022	Tanoura Elementary School	Grade 6	Job lecture: What is methylmercury?	27
March 1	Sashiki Elementary School	Grade 5	A talk on mercury	61
April 22	Minamata High School	Second year	General exploration: An exploration lecture: Let's make a poster	64
June 10	Minamata High School	Second year	General exploration: An exploration lecture	11
June 14	Tanoura Elementary School	Grades 1, 2 and 3	How to get along with wildlife: What distance is just right? (Collaboration project with Dr. Tsuyoshi Ishinazaka, Shiretoko Nature Foundation) Species-based differences between cranial bones of bear, sea lion and Yezo deer	92
June 15	Kurohiji Elementary School	Grade 5	What kind of illness is Minamata disease? How to get along with wildlife (Collaboration project with Dr. Tsuyoshi Ishinazaka, Shiretoko Nature Foundation) Differences between cranial bones of bear, sea lion and Yezo deer	27
June 15	Minamata Environmental Academia	General public - Elementary, junior high school and high school students	Wilderness protection activities in Shiretoko, Hokkaido (Collaboration project with Dr. Tsuyoshi Ishinazaka, Shiretoko Nature Foundation)　 Differences between cranial bones of bear, sea lion and Yezo deer	20
June 16	Sashiki Elementary School	Grade 5	How to get along with wildlife (Collaboration project with Dr. Tsuyoshi Ishinazaka, Shiretoko Nature Foundation) Differences between cranial bones of bear, sea lion and Yezo deer	37
June 16	Sashiki Elementary School	Second year	Differences between cranial bones of bear, sea lion and Yezo deer	35
June 24	Minamata High School	Second year	General exploration: An exploration lecture	11
July 8	Minamata High School	Second year	General exploration: An exploration lecture	11
July 15	Minamata High School	Second year	General exploration: An exploration lecture	3
August 4	Minamata Environmental Academia	Elementary and junior high school students	Let's extract DNA!	4
September 2	Minamata High School	Second year	General exploration: An exploration lecture	7
September 9	Minamata High School	Second year	General exploration: An exploration lecture	5
September 30	Minamata High School	Second year	General exploration: An exploration lecture	13
October 11	Makuhari High School, Shibuya Education Academy	Second year	Mercury: A cause of major pollution incidents	12
October 12	Sashiki Elementary School	Grade 5	Mercury: A cause of major pollution incidents	41
October 14	Minamata High School	Second year	General exploration: An exploration lecture	2
October 21	Minamata High School	Second year	General exploration: An exploration lecture	1
November 4	Minamata High School	Second year	General exploration: An exploration lecture	2
November 5	Minamata Dai-Ichi Elementary School	Grades 4, 5 and 6	What researchers do: Hands-on experience of a veterinarian's job (Issho Festival)	34
November 11	Minamata High School	Second year	General exploration: An exploration lecture	3
November 18	Minamata High School	Second year	General exploration: An exploration lecture	3
November 25	Minamata High School	Second year	General exploration: An exploration lecture	2
December 1	Minamata High School	Second year	General exploration: An exploration lecture	8
December 2	Minamata High School	Second year	General exploration: An exploration lecture	4
December 9	Minamata High School	Second year	General exploration: An exploration lecture	7
December 12	Kanagawa Gakuen High School	First year	Mercury: What is methylmercury?	8
December 16	Minamata High School	First to third years	Environmental education talk	19
January 13	Minamata High School	Second year	General exploration: An exploration lecture	6
January 20	Minamata High School	Second year	General exploration: An exploration lecture	4

Externally-funded research

FY2017-2019 Environment Research and Technology Development Fund, Theme number 5-1704 (Co-Investigator)

Development of a mercury-exposure measuring system in the environment and its vicinities involving mercury use
FY 2007-2011 Grant-in-Aid for Young Scientists (B) (Principal Investigator)

Elucidation of the mechanism of methylmercury-caused extrapyramidal disturbance

Main career history, academic history, academic degrees, awards, etc.

Veterinarian qualification
Class B Group 1 Hazardous Materials Engineer
Class B Group 2 Hazardous Materials Engineer
Class B Group 3 Hazardous Materials Engineer
Class B Group 4 Hazardous Materials Engineer
Class B Group 5 Hazardous Materials Engineer
Class B Group 6 Hazardous Materials Engineer
Nursery Teacher
Food Sanitation Supervisor
Domestic Animal Inseminator
Second Class Boat's Operator
Ph.D. in Veterinary Medicine
Registered Pharmaceutical Sales Clerk
Trap Hunting license
Type 2 Gun Hunting License
Member of the Document Management Committee, Minamata Disease Municipal Museum (2022-)
Member of the Project Promotion Council, Minamata Environmental Academia (2020-)
Collaborative Researcher of the Laboratory of Neuropathology, Tokyo Metropolitan Institute of Medical Science (2018-)

About NIMD

Our organization, departments, staff and researchers

Masumi Marumoto

Research theme - Areas of work

Main research achievements

Externally-funded research

Main career history, academic history, academic degrees, awards, etc.