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The goal of our study was to identify pharmaceuticals, their potential sources and consumption level in two different socioeconomic and geographical regions-Bordeaux, France and Kharkiv, Ukraine. These substances were monitored in rivers water during contrasted seasonal conditions with application of passive samplers. The 21 pharmaceuticals (psychiatric drugs: alprazolam, amitriptyline, diazepam, fluoxetine, nordiazepam, carbamazepine, bromazepam; analgesics: aspirin, paracetamol; broncholidator: clenbuterol, salbutamol, terbutaline; non-steroidal anti-inflammatory drug: diclofenac, ibuprofen, ketoprofen, naproxen; lipid regulator: gemfibrozil; stimulants: caffeine, theophylline) were identified in sites upstream and downstream of urban areas and discharge of wastewaters. Caffeine, carbamazepine, and diclofenac were relatively abundant into the surface water and could be considered as potential anthropogenic markers of wastewater discharges into rivers. A mass balance modeling has been applied to calculate approximate consumption rates for carbamazepine, diclofenac, and caffeine in both regions to assess socio-economic factors linked with pharmaceuticals behavior. [ABSTRACT FROM AUTHOR]

Summary: Hydrochemical and stable isotopic (2H, 18O) data were used to characterize the groundwater flow and major chemical features within a complex fractured volcanic aquifer system, the Argnat basin, which is located in the Chaîne des Puys (French Massif Central). From 10 sampling points, the study of the transfer into the saturated zone from upstream to downstream, given the geological context and topography, allows to estimate the role of supply from high and low altitudes to the recharge processes. This work shows the existence of different types of supply between pahoehoe and a’a flows. Therefore, the morphology of volcanic flows impacts the chemical and isotopic signatures of groundwater, enhancing or reducing the influence of the unsaturated zone on the pathways of infiltrated water. Pahoehoe flows imply horizontal water flows of low discharge at the top of the lava whereas a’a flows seems to be much more heterogeneous and locally able to promote the existence of perched water bodies and further vertical circulations. Taking into account these two types of behaviour, a conceptual scheme of the functioning of this heterogeneous environment is proposed, which will help towards a sustainable management of volcanic aquifers in relation with the . [ABSTRACT FROM AUTHOR]

The present study investigates the chemical composition of wet atmospheric precipitation samples on a daily and an intra-event timescales in Opme, an experimental meteorological station located near Clermont-Ferrand, France. The samples have been collected from November 2005 to October 2007. A total of 217 rainwater samples, integrated for 24 h, were collected and analyzed for pH, conductivity, Na+, K+, Mg2+, NH, Ca2+, Cl−, NO , SO , PO and HCO. The composition of the rainwater collected appeared to be controlled by the following potential sources: neutralisation process (association among calcium, ammonium with nitrate and sulphate), marine and terrestrial sources. In order to determine the role of long-range transport, the integrated events were classified according to four origins of air-masses: (1) West, (2) North and East, (3) South including Iberian and Italian Peninsulae and (4) local. This analysis allows identifying the source areas of the different association of elements defined. Although calcium is always dominant, total content of rainfall is variable and neutralisation process can be more or less efficient and specific. Rainout (long-range transport) and washout (below-cloud scavenging) were investigated through intra-event measurements of chemical species. Four rain-events have been selected according to the four classes of origins of air-masses. It appears that the first fractions are responsible for an important part of the chemical content of the whole event. Terrestrial species, locally emitted, induce the neutralisation process of acid species. Local meteorological conditions, such as wind’s speed and direction, play an important role as they could provoke recharges of the below cloud air column during the event. [ABSTRACT FROM AUTHOR]

From March 1997 to March 1999, sequential rainwater samples were collected during 12 rainfalls at Avignon, Southern France, with the objective of investigating how the formation conditions affect the isotopic composition of the most frequent rain types occurring in the western Mediterranean region. Three major isotopic trends were identified: (i) a descending δ18O trend, produced when a cold front penetration causes the rise of warm and humid air masses, accompanied by adiabatic cooling and precipitation. The temperature variation is the predominant feature of frontal rainfalls; (ii) an L-shaped δ18O trend, which can be produced by convective rains, with an initial rapid decrease followed by a stationary value; (iii) a V-shaped trend, in which the final phase of precipitation obeys a different mechanism from the first phase. Frontal and convective rainfalls may produce this trend.Three heavy rainfalls were selected for applying a numerical Rayleigh condensation model to describe their isotopic trends. Some irregularities in the generally monotonously decreasing isotopic trend were attributed to inputs of new air masses, which were often recorded by chemical variations as well. The numerical model indicates that about 80, 60 and 45% of the vapour initially present was condensed. The lowest fraction corresponds to the most abundant rainfall, and it is due to the convective nature of the latter implying a continuous supply of condensable vapour. [Copyright &y& Elsevier]