Uranium in agricultural soils and drinking water wells on the Swiss Plateau

Abstract

Mineral phosphorus fertilizers are regularly applied to agricultural sites, but their uranium (U) content is potentially hazardous to humans and the environment. Fertilizer-derived U can accumulate in the soil, but might also leach to ground-, spring and surface waters. We sampled 19 mineral fertilizers from the canton of Bern and soils of three arable and one forest reference sites at each of four locations with elevated U concentrations (7-28 μg L) in nearby drinking water wells. The total U concentrations of the fertilizers were measured. The soils were analysed at three depth intervals down to 1 m for general soil parameters, total Cd, P, U and NaHCO-extractable U concentrations, and U activity ratios (AR). The U concentrations and AR values of the drinking water samples were also measured. A theoretical assessment showed that fertilizer-derived U may cause high U concentrations in leaching waters (up to approx. 25 μg L), but normally contributes only a small amount (approx. 0-3 μg L). The arable soils investigated showed no significant U accumulation compared to the forest sites. The close positive correlation of AR with NaHCO-extractable U (R = 0.7, p < 0.001) indicates that application of fertilizer can increase the extractable U pool. The lack of depth gradients in the soil U concentrations (1.5-2.7 mg kg) and AR (0.90-1.06) ratios are inconsistent with the accumulation of U in the surface soil, and might indicate some leaching of fertilizer-derived U. The AR values in the water samples were close to 1, possibly suggesting an influence of fertilizer-derived U. However, based on findings from the literature and considering the heterogeneity of the catchment area, the agricultural practices, and the comparatively long distance to the groundwater, we conclude that fertilizer-derived U makes only a minor contribution to the elevated U concentrations in the water samples.

Critical accumulation of fertilizer-derived uranium in Icelandic grassland Andosol

“…Since the transfer factor of U from soil to plant is below 1% [8,14], the U uptake by plants and then entering the food chain is not a predominant health issue [13]. However, it has been suggested that drinking water can become a main source of human U intake [15,16]. A number of studies indicate the transfer of fertilizerderived U to water bodies [16][17][18][19].…”

“…However, it has been suggested that drinking water can become a main source of human U intake [15,16]. A number of studies indicate the transfer of fertilizerderived U to water bodies [16][17][18][19].…”

Applying a multiscale systems biology approach to study the effect of chronic low-dose exposure to uranium in rat kidneys

“…Low doses of uranium can be easily ingested by mammals from many sources including spring water, phosphate fertilizers, nuclear fuel exploitation, and military weapons. Depending on where they live, therefore, human populations can be chronically exposed to low doses of environmental uranium (Pereira et al 2014;Zhivin et al 2014;Jakhu et al 2016;Besic et al 2017;Bigalke et al 2018;Faa et al 2018).…”

Obsahy přirozených radioaktivních prvků (K, U, Th) v půdách na mapovém listu 24-22 Olomouc – vztah mezi radioaktivitou půdy a matečné horniny

“…Fosforečná hnojiva vyráběná ze surovin pocházejících z ložisek sedimentárního původu mohou mít značné obsahy uranu, běžně v řádu desítek ppm, někdy i více než 100 ppm -vysoké koncentrace uranu v hnojivech mohou mít vliv nejen na radioaktivitu půdy, ale mohou být toxické pro rostlinstvo, dlouhodobá aplikace takových hnojiv může způsobit zvýšení koncentrace uranu v podzemní vodě se všemi následnými dopady (viz např. Guzmán et al 1995;Yamazaki, Geraldo 2003;Liesch et al 2015;Bigalke et al 2018;Selvakumar et al 2018). Německá "Komise pro ochranu půdy" doporučila omezení koncentrace uranu v hnojivech legislativní cestou, kdy za mezní koncentraci považuje 50 mg uranu na 1 kg P 2 O 5 (na základě informace zveřejněné na wwww.agris.…”