Bioavailability in soils

The consumption of locally-produced vegetables by humans may be an important exposure pathway for soil contaminants in many urban settings and for agricultural land use. Hence, prediction of metal and metalloid uptake by vegetables from contaminated soils is an important part of the Human Health Risk Assessment procedure. The behaviour of metals (cadmium, chromium, cobalt, copper, mercury, molybdenum, nickel, lead and zinc) and metalloids (arsenic, boron and selenium) in contaminated soils depends to a large extent on the intrinsic charge, valence and speciation of the contaminant ion, and soil properties such as pH, redox status and contents of clay and/or organic matter. However, chemistry and behaviour of the contaminant in soil alone cannot predict soil-to-plant transfer. Root uptake, root selectivity, ion interactions, rhizosphere processes, leaf uptake from the atmosphere, and plant partitioning are important processes that ultimately govern the accumulation ofmetals and metalloids in edible vegetable tissues. Mechanistic models to accurately describe all these processes have not yet been developed, let alone validated under field conditions. Hence, to estimate risks by vegetable consumption, empirical models have been used to correlate concentrations of metals and metalloids in contaminated soils, soil physico-chemical characteristics, and concentrations of elements in vegetable tissues. These models should only be used within the bounds of their calibration, and often need to be re-calibrated or validated using local soil and environmental conditions on a regional or site-specific basis.Mike J. McLaughlin, Erik Smolders, Fien Degryse, and Rene Rietr

How local is local? Evidence from bank competition and corporate innovation in U.S.

This paper aims to fill in a research gap in the effects of bank competition on corporate innovation. In addition to the evidence on the favorable effects of bank competition on corporate innovation, we show novel evidence on the substitution effects of bank competition in a wider region and neighbor-state to local bank competition in financing corporate innovation activities. In banking market, we show ‘how local is local’ depends on the operating scope and information transparency of firms. Local banks have an information advantage over distant banks in financing local businesses and informationally opaque corporate innovation activities

Provenance of white marbles from the Nabatean Sites of Qasr Al Bint and the collonaded street baths at Petra, Jordan

Intercultural relations and trade are important components of understanding of historical interrelationships between regions and cultures. One of the most interesting objects of trade is stone, because of the expense and difficulty of its transport. Thus, the source of marble used in the Nabatean city of Petra was investigated using established petrological, geochemical and isotopic analyses. Specifically, marble from Qasr al Bint and the Colonnaded Street baths were sampled and investigated. The results of these analyses show that the marbles came from sources in Asia Minora and Greece. The most likely sources of the marble are the quarries of Thasos, Penteli, Prokennesos and Dokimeion. The choice of marble followed the desired utilitarian and aesthetic function of the stone. These results show that active trade in stone was part of the cultural interaction of the period.status: publishe