Other issues to be urgently addressed.
Title of Research:
19_R05-01

Study on the contribution of microplastics to bioaccumulation andbiological magnification towards fish
Principal Investigator:
Tatarazako Norihisa（Professor, Ehime University, Graduate School of Agriculture）
3-5-7 Tarumi, Matsuyama, Ehime, 790-8566 Japan
Collaborators:
Tatsuhiro Niino (LSI Medience Corporation)
1000 Kamoshidacho, Aoba-ku, Yokohama-shi, Kanagawa 227-0033, Japan
Shin Takahashi（Ehime University, Graduate School of Agriculture）
3-5-7 Tarumi, Matsuyama, Ehime, 790-8566 Japan
Yoshifumi Horie (Akita Prefectural Univesity)
241-438 Kaidobata-Nishi Nakano Shimoshinjo Akita City 010-0195 Japan
Summary of Research:
The microplastics (MPs) are detected from sewage treated water or sea water, and harmful
chemical substances are known to adsorbed to those MPs. And there is a concern about thoseadsorbed chemicals may be taken more efficiently to organisms intermediated by MP and that
biological concentration or biological magnification is accelerated. Our study will try to clarify
whether the chemical substances adhered to MP are eluted, and absorbed / transferred /accumulated in the body of organisms.
This year, we reviewed the kind of solvent to be adsorbed on MP of PAHs and the quantitative
analysis procedure, and when the amount of adsorption was re-measured under new procedure,
the result was PE> PP> TF. A significant correlation was observed between the amount of PAHsadsorbed and the octanol / water partition coefficient. Furthermore, the amount of PAHs adsorbed
on MP was higher in seawater than in pure water. It is necessary to confirm the acute toxicity ofMPB itself in medaka and daphnia in order to determine the set concentration for the accumulation
test. Medaka did not die with MPB of all sizes, whereas daphnia showed acute toxicity with MPB of0.2 and 0.5 μm in diameter. Medaka was toxic to benzo [a] pyrene and pyrene in an extended
acute toxicity test. When larvae and Daphnia larvae were fed 5 μm-diameter fluorescent MPB andobserved under a microscope, both were confirmed to accumulate MPB in the digestive tract, butno transfer to other internal organs and muscle tissues was observed. In addition, in order toexamine biomagnification, it was examined whether fluorescent MP was transferred to juvenile
medaka through daphnia. Although water flea was eaten by medaka, MPB was transferred, but noaccumulation of MPB was detected.
In the next fiscal year, we will determine the concentration of chemicals accumulated in fish byfeeding MPs with PAHs adsorbed. The transfer efficiency is determined from the total intake andthe amount of chemicals in the fish.
Timeline:
March 1, 2019 - February 29, 2020
Topics:Poster presentation at JCIA LRI Annual Workshop 2019 “Study on the contribution of microplastics
to bioaccumulation and biological magnification towards fish” (Tokyo, August 30th, 2019)
Publications:
1.
2.
3.

Norihisa Tatarazako, Kazufumi Misawa, Yukiyo Okazaki, SETAC Europe 29th Annual Meeting
26−30 May 2019 | Helsinki, Finland,poster
Yukiyo Okazaki, Takahiro Ishizaka, Norihisa Tatarazako, SETAC Europe 29th Annual Meeting
26−30 May 2019 | Helsinki, Finland,poster
Norihisa Tatarazako, Yukiyo Okazaki, SETAC North America 40th Annual Meeting 3–7 November
2019, Metro Toronto Convention Centre, Toronto, Ontario

Other issues to be urgently addressed.
4.

Yukiyo Okazaki, Norihisa Tatarazako, Shin Takahashi, Harumi Kasahara, Yaeko Sera, Tatsuhiro
Niino, SETAC North America 40th Annual Meeting 3–7 November 2019, Metro Toronto Convention
Centre, Toronto, Ontario