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Mercury levels in hair are associated with reduced neurobehavioral performance and altered brain structures in young adults.

ABSTRACT: The detrimental effects of high-level mercury exposure on the central nervous system as well as effects of low-level exposure during early development have been established. However, no previous studies have investigated the effects of mercury level on brain morphometry using advance imaging techniques in young adults. Here, utilizing hair analysis which has been advocated as a method for biological monitoring, data of regional gray matter volume (rGMV), regional white matter volume (rWMV), fractional anisotropy (FA) and mean diffusivity (MD), cognitive functions, and depression among 920 healthy young adults in Japan, we showed that greater hair mercury levels were weakly but significantly associated with diminished cognitive performance, particularly on tasks requiring rapid processing (speed measures), lower depressive tendency, lower rGMV in areas of the thalamus and hippocampus, lower rWMV in widespread areas, greater FA in bilaterally distributed white matter areas overlapping with areas of significant rWMV reductions and lower MD of the widely distributed gray and white matter areas particularly in the bilateral frontal lobe and the right basal ganglia. These results suggest that even normal mercury exposure levels in Japan are weakly associated with differences of brain structures and lower neurobehavioral performance and altered mood among young adults.

SUBMITTER: Takeuchi H

PROVIDER: S-EPMC9163068 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Mercury levels in hair are associated with reduced neurobehavioral performance and altered brain structures in young adults.

Takeuchi Hikaru H Shiota Yuka Y Yaoi Ken K Taki Yasuyuki Y Nouchi Rui R Yokoyama Ryoichi R Kotozaki Yuka Y Nakagawa Seishu S Sekiguchi Atsushi A Iizuka Kunio K Hanawa Sugiko S Araki Tsuyoshi T Miyauchi Carlos Makoto CM Sakaki Kohei K Nozawa Takayuki T Ikeda Shigeyuki S Yokota Susumu S Magistro Daniele D Sassa Yuko Y Kawashima Ryuta R

Communications biology 20220602 1

The detrimental effects of high-level mercury exposure on the central nervous system as well as effects of low-level exposure during early development have been established. However, no previous studies have investigated the effects of mercury level on brain morphometry using advance imaging techniques in young adults. Here, utilizing hair analysis which has been advocated as a method for biological monitoring, data of regional gray matter volume (rGMV), regional white matter volume (rWMV), frac ...[more]

PMID: 35655003

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Mercury levels in hair are associated with reduced neurobehavioral performance and altered brain structures in young adults.

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Mercury levels in hair are associated with reduced neurobehavioral performance and altered brain structures in young adults.

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