Spatio-temporal trends of polybrominated dibenzo-p-dioxins and dibenzofurans in archived sediments from Tokyo Bay, Japan

Akitoshi Goto; Nguyen Minh Tue; Masayuki Someya; Tomohiko Isobe; Shin Takahashi; Shinsuke Tanabe; Tatsuya Kunisue

doi:10.1016/j.scitotenv.2017.04.166

Spatio-temporal trends of polybrominated dibenzo-p-dioxins and dibenzofurans in archived sediments from Tokyo Bay, Japan

Sci Total Environ. 2017 Dec 1:599-600:340-347. doi: 10.1016/j.scitotenv.2017.04.166. Epub 2017 May 4.

Authors

Akitoshi Goto¹, Nguyen Minh Tue¹, Masayuki Someya², Tomohiko Isobe³, Shin Takahashi⁴, Shinsuke Tanabe¹, Tatsuya Kunisue⁵

Affiliations

¹ Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan.
² Tokyo Metropolitan Research Institute for Environmental Protection, 1-7-5 Shinsuna Koto, Tokyo 136-0075, Japan.
³ Integrated Health Risk Assessment Section, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
⁴ Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan; Center of Advanced Technology for the Environment, Agricultural Faculty, Ehime University, 3-5-7 Tarumi, Matsuyama, Japan.
⁵ Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan. Electronic address: kunisue.tatsuya.ew@ehime-u.ac.jp.

PMID: 28478363
DOI: 10.1016/j.scitotenv.2017.04.166

Abstract

The present study examined the occurrence and potential sources of mono- to octa-brominated dibenzo-p-dioxins/dibenzofurans (Mo-OBDD/Fs) in Tokyo Bay, Japan, using surface sediments and ²¹⁰Pb-dated sediment cores (covering the period 1895-2000) collected in 2002. The results showed a clear difference in the spatio-temporal trend between PBDFs and PBDDs. The spatial distribution of PBDF concentrations in the surface sediments showed a decreasing trend from the head to the mouth of the bay, which was similar to that of polybrominated diphenyl ethers (PBDEs) reported previously for the same sediment samples. In the sediment cores, PBDF and PBDE concentrations increased drastically after the 1960s and reached the highest levels in the late 1990s. In addition, a significant positive correlation was observed between the concentrations of their predominant congeners, 1,2,3,4,6,7,8-HpBDF and BDE-209. These results indicate that main contamination sources of PBDFs were technical PBDE formulations, especially DecaBDE. In contrast, total PBDDs in the surface sediments were rather uniform in the whole area of the bay. Furthermore, in the sediment cores, PBDD levels showed marginal fluctuation over the past century, with the predominance of 2,7-/2,8-DiBDDs and 1,3,7-/1,3,8-TrBDDs in all the sediment layers. It is noteworthy that these PBDD congeners were also found in the sediment layers corresponding to the pre-industrial era, supporting their natural formation in the coastal environment.

Keywords: Historical trend; PBDD/Fs; PBDEs; PCDD/Fs; Potential risk.