Magnetite pollution nanoparticles in the human brain

Maher, Barbara Ann and Ahmed, Imad and Karloukovski, Vassil Vassilev and MacLaren, Donald and Foulds, Penelope and Allsop, David and Mann, David and Torres-Jardon, Ricardo and Calderon-Garciduenas, Lilian (2016) Magnetite pollution nanoparticles in the human brain. Proceedings of the National Academy of Sciences of the United States of America, 113 (39). pp. 10797-10801. ISSN 0027-8424

[img]
Preview
PDF (As published Maher et al Magnetitepollution nanoparticles in the human brain incl Methods)
As_published_Maher_et_al_Magnetitepollution_nanoparticles_in_the_human_brain_incl_Methods.pdf - Accepted Version
Available under License Creative Commons Attribution-NonCommercial.

Download (1MB)
[img]
Preview
PDF (Supplementary Information Figs re-ordered Aug 25 2016)
SI_Figs_re_ordered_Aug_25_2016.pdf - Accepted Version
Available under License Creative Commons Attribution-NonCommercial.

Download (1MB)

Abstract

Biologically-formed nanoparticles of the strongly magnetic mineral, magnetite, were first detected in the human brain over 20 years ago (Kirschvink, J.L., Kobayashi-Kirschvink, A. & Woodford, B.J., 1992, Magnetite Biomineralization in the Human Brain. P Natl Acad Sci USA 89(16):7683-7687). Magnetite can have potentially large impacts on the brain due to its unique combination of redox activity, surface charge and strongly magnetic behaviour. We used magnetic analyses and electron microscopy to identify the abundant presence in the brain of magnetite nanoparticles that are consistent with high-temperature formation, suggesting therefore an external, not internal, source. Comprising a separate nanoparticle population from the euhedral particles ascribed to endogenous sources, these brain magnetites are often found with other transition metal nanoparticles, and they display rounded crystal morphologies and fused surface textures, reflecting crystallization upon cooling from an initially heated, iron-bearing source material. Such high-temperature magnetite ‘nanospheres’ are ubiquitous and abundant in airborne particulate matter (PM) pollution. They arise as combustion- derived, iron-rich particles, often associated with other transition metal particles, which condense and/or oxidise upon airborne release. Those magnetite pollutant particles which are < ~200 nm in diameter can enter the brain directly via the olfactory bulb. Their presence proves that externally sourced iron-bearing nanoparticles, rather than their soluble compounds, can be transported directly into the brain, where they may pose hazard to human health.

Item Type:
Journal Article
Journal or Publication Title:
Proceedings of the National Academy of Sciences of the United States of America
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/1000
Subjects:
ID Code:
81582
Deposited By:
Deposited On:
20 Sep 2016 07:50
Refereed?:
Yes
Published?:
Published
Last Modified:
08 Apr 2020 03:28