Radiocesium in caribou and reindeer in northern Canada, Alaska and Greenland from 1958 to 2000

Transfer parameter values in temperate forest ecosystems: a review

“…Caribou lives wild in the arctic tundra, mountain tundra, and northern forests of North America, Russia, and Scandinavia. The best fit for a long-term rate of uptake normalized to the deposition of 137 Cs was 0.68 m 2 a À1 kg À1 wet weight (MacDonald et al, 2007). The parameter was derived from the monitoring data of North American caribou in the period from the mid-1960s to the late 1980s, and it thus represents varying annual deposition of 137 Cs.…”

Cadmium and other elements in tissues from four ungulate species from the Mackenzie Mountain region of the Northwest Territories, Canada

“…The 137 Cs found in all four species is primarily a remnant of the nuclear weapons test in the 1960s, indicating that significant levels of 137 Cs are still present in the terrestrial system (Macdonald et al, 2007). The effective half-life of the isotope in barren-ground caribou in northern Canada has been shown to be about 6 years (Macdonald et al, 2007). The tissue samples for this study were mostly collected in the autumn and the Cs levels are probably at the maximum annual levels in these species, since atmospheric deposition from Fukushima peaked in March/April in 2011.…”

“…134 Cs is an anthropogenically-derived isotope with a half-life of 2.1 years and is only released to the environment during nuclear reactor accidents. Macdonald et al (2007) used 134 Cs as a marker to estimate the amount of longer-lived 137 Cs (t½¼ 30.2 years) in barren-ground caribou in Canada from the Chernobyl reactor accident in 1986. Emissions from the Fukushima nuclear plant began on March 12, 2011 and the plume reached North America on approximately March 19, 2011 (Wetherbee et al, 2012).…”

“…Man-made radionuclides, such as cesium and iodine isotopes, are also of concern for northern residents. These isotopes are released during the major nuclear accidents Chernobyl and Fukushima, and transport to the Arctic, followed by accumulation in lichen and other vegetation and in wildlife (Macdonald et al, 1996(Macdonald et al, , 2007. In many cases, the reasons behind the regional elevation of individual metals in large game species are unclear, and the importance of the local mineralization of soils (Reimann et al, 2015) relative to atmospheric deposition from distant anthropogenic sources is not well defined.…”

Hyper-accumulation of legacy fallout radionuclides in cryoconite on Isfallsglaciären (Arctic Sweden) and their downstream distribution

“…There has been a considerable research effort in understanding the uptake of FRNs within flora and fauna, particularly following the 1986 Chernobyl accident. Mosses, lichens, and fungi are environmental matrices known to efficiently accumulate FRNs (Heinrich, 1992;Steinnes and Njåstad, 1993), and play a crucial role in radionuclide uptake into the food chain, particularly for reindeer and other ruminants (MacDonald et al, 2007). The effect of deposition of 137 Cs from atmospheric transport following the Chernobyl accident was considerable for reindeer herding in Sweden, Norway, and other northern countries, due to contamination of the lichen-reindeer-human food chain (Skuterud et al, 2016), and a number of studies have demonstrated the importance of origin (food source) for 137 Cs transfer, highlighting the lichen content of diets as a key control on uptake (Ahman et al, 2001;Skuterud et al, 2004).…”