Radionuclides from past uranium mining in rivers of Portugal

Preliminary assessment of uranium mining legacy and environmental radioactivity levels in Sabugal region, Portugal

“…Radionuclides were accumulated up to different levels, and, generally, radium ( 226 Ra) and lead ( 210 Pb) were the most concentrated by plants, while uranium, thorium, and polonium isotopes were less accumulated. This is in agreement with the previous results on the mobility of radionuclides in the environment [14][15][16][17]. Amongst plants, the leafy ones, such as lettuce, usually displayed higher radionuclide concentrations, while roots, such as carrot and onion, were lower.…”

Quality and mutagenicity of water and sediment of the streams impacted by the former uranium mine area Olší–Drahonín (Czech Republic)

“…The results are given in mg/kg of dry matter. A similar procedure for processing sediment samples for uranium determination, including sieving, in order to eliminate the influence of coarse fractions (sand, gravel), was also used in monitoring areas of the former uranium mining in Portugal (Carvalho, 1995;Carvalho et al, 2007) and Germany (Sitte et al, 2010). In 2010, a detailed screening of metals and arsenic content was carried out in all tested samples of sediment.…”

“…Although worldwide attention has been given to the issue of environmental burden in the mining of uranium mines in last two decades (Van Dam et al, 2002;Meinrath et al, 2003;Carvalho et al, 2005Carvalho et al, , 2007, the lack of data on toxicity and mutagenicity of surface water and sediments, particularly from the mining of uranium and its compounds is still evident and studies of the topic are rare (Pereira et al, 2009). Tests of toxicity and genotoxicity represent the important role in the environmental pollution studies.…”

“…The same approach was chosen for monitoring the impact of uranium mining and processing, including the period after the mines were abandoned, in other European countries, Germany (Meinrath et al, 2003), Portugal (Carvalho et al, 2007) and Romania (Filip, 2009).…”

Bioaccumulation and lack of oxidative stress response in the ragworm H. diversicolor following exposure to 226Ra in sediment

“…The activity in the sediment for the exposed groups in this study was in the range 470-6600 Bq kg À1 sediment, which covers more than two orders of magnitude higher radiation from 226 Ra than the background level. The exposure concentrations used were therefore sufficiently high to include levels of radium found near sources such as mines (100-2000 Bq kg À1 sediment (Carvalho et al, 2007), but presumably much higher than that found in any area of the North Sea as a result of produced water inputs (cf Gä fvert and Faerevik, 2004)). 226 Ra added to sediment was sufficiently mobile to cause proportionally increased activity in pore water and in the sedimentdwelling polychaete H. diversicolor at the two exposure levels.…”