Comparison of the behaviour of manufactured and other airborne nanoparticles and the consequences for prioritising research and regulation activities

Currently, there are no air quality regulations in force in any part of the world to control number concentrations of airborne atmospheric nanoparticles (ANPs). This is partly due to a lack of reliable information on measurement methods, dispersion characteristics, modelling, health and other environmental impacts. Because of the special characteristics of manufactured (also termed engineered or synthesised) nanomaterials or nanoparticles (MNPs), a substantial increase is forecast for their manufacture and use, despite understanding of safe design and use, and health and environmental implications being in its early stage. This article discusses a number of underlining technical issues by comparing the properties and behaviour of MNPs with anthropogenically produced ANPs. Such a comparison is essential for the judicious treatment of the MNPs in any potential air quality regulatory framework for ANPs

The distribution of 137Cs in maize (Zea mays L.) and two millet species (Panicum miliaceum L. and Panicum maximum Jacq.) cultivated on the caesium-contaminated soil

The plants of three species (Zea mays L., Panicum miliaceum L. and Panicum maximum Jacq.) were grown on the soil contaminated with 0.3 mM CsCl solution traced with 137Cs, in the greenhouse. For all the species, the fresh-to-dry weight ratio was equal in the caesium-treated plants and in the control group after 3 weeks of culture. The shoot-to-root fresh weight and dry weight ratios were decreased in maize, unchanged in Panicum miliaceum and increased in Panicum maximum, comparing to the control without caesium treatment. The shoot/soil and also root/soil transfer factors (TF) for 137Cs (measured by means of NaI gamma spectrometer) were always the highest in maize, then lower in Panicum miliaceum and the lowest in Panicum maximum. All the plants seem to be hyperaccumulators of caesium. The root/soil TF was especially high in maize, i.e. 55 (kBq kg 1 biomass)/(kBq kg 1 soil). The shoot/root concentration factor (CF) for 137Cs was the lowest in maize, higher in Panicum miliaceum and the highest in Panicum maximum. The hyperaccumulation of 137Cs in the whole plant was the highest in maize, lower in Panicum miliaceum and the lowest in Panicum maximum. The proved ability of the investigated plants for phytoextraction of the soil caesium points to the possibility to utilise these plants in the soil bioremediation. From this point of view, Panicum maximum seems to be the most useful plant because it accumulates caesium mainly in the shoot, and maize would be the least useful species since it has the highest accumulation in the root

Platinum uptake by mustard (Sinapis alba L.) and maize (Zea mays L.) plants

The ability of platinum uptake by hydroponically cultivated plants - Indian mustard (Sinapis alba L.) and Anawa maize (Zea mays L.) - was investigated. The efficiency of the transport of platinum compounds from the roots to above ground organs was estimated. For platinum determination in plant samples, digested in closed system with microwave energy, very sensitive analytical methods were applied - adsorptive stripping voltammetry (AdSV) and mass spectrometry with inductively coupled plasma (ICP-MS). For validation of the obtained results the recovery of platinum was examined. The accumulation factors (AF) of platinum: more then 800 and 400 for roots of Indian mustard and Anawa maize, respectively and about 90 and 30 for above ground organs of both species were found