Analysis of particulate distributed across Fukushima Prefecture: attributing provenance to the 2011 Fukushima Daiichi Nuclear Power Plant accident or an alternate emission source.

In contrast to investigating the distribution (and state) of these high-activity fission products, this study examined fragments of transition metals, rare earth elements and actinides found adhered to a diverse range of organic samples collected from localities across the radiologically contaminated Fukushima Prefecture. As well as varying enormously in their elemental composition, the entrapped particulates comprised a wide size range (150 nm to >10 μm). For particulate of certain compositions (including Ag, Ce, Sm, and Au), a correlation was observed between their size and the distance at which they were encountered from the FDNPP. While a trend was apparent for these and several other composition particles, other materials (including Zr, Pb, Sn, and Ba) could not be described by such a strongly-negative linear trend. Although a Fukushima provenance could be apportioned to a component of the material, an alternate source is necessary to account for a significant inventory of the particulate material. While contrasting provenances may exist, both the size and composition of this particulate could represent potentially significant health implications for exposed populations.