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Golubev AV Golubeva VN Krylov NG Kuznetsova VF Mavrin SV Aleinikov AY Hoppes WG Surano KA 《Journal of environmental radioactivity》2005,84(3):333-342
Lichens are widely used to assess the atmospheric pollution by heavy metals and radionuclides. However, few studies are available in publications on using lichens to qualitatively assess the atmospheric pollution levels. The paper presents research results applying epiphytic lichens as bio-monitors of quantitative atmospheric contamination with uranium. The observations were conducted during 2.5 years in the natural environment. Two experimental sites were used: one in the vicinity of a uranium contamination source, the other one - at a sufficient distance away to represent the background conditions. Air and lichens were sampled at both sites monthly. Epiphytic lichens Hypogimnia physodes were used as bio-indicators. Lichen samples were taken from various trees at about 1.5m from the ground. Air was sampled with filters at sampling stations. The uranium content in lichen and air samples as well as isotopic mass ratios (235)U/(238)U were measured by mass-spectrometer technique after uranium pre-extraction. Measured content of uranium were 1.45 mgkg(-1) in lichen at 2.09 E-04 microgm(-3) in air and 0.106 mgkg(-1) in lichen at 1.13 E-05 microgm(-3) in air. The relationship of the uranium content in atmosphere and that in lichens was determined, C(AIR)=exp(1.1 x C(LICHEN)-12). The possibility of separate identification of natural and man-made uranium in lichens was demonstrated in principle. 相似文献
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The viruses primarily associated with shellfish-borne illness are norovirus, causing gastroenteritis and hepatitis A virus
(HAV). Recent years have seen a proliferation of publications on methods for detection of these viruses in shellfish using
polymerase chain reaction (PCR). However, currently no standard harmonised procedures have been published. Standardisation
is necessary before virus methods can be considered for adoption within a regulatory framework. A European standardisation
working group is developing a two-part (quantitative and qualitative) standard method for virus detection in foodstuffs, including
shellfish, which has the potential to be incorporated into EU legislation as a reference method. This article describes the
development of the standard method and outlines the key methodology principles adopted, the controls and other quality assurance
measures supporting the method and future necessary developments in the area. 相似文献
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