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Anthropogenic activities induce significant alterations of the macromolecular organic matter (MOM) in riverine systems mainly by emission of pollutants and their subsequent incorporation into geopolymers (bound residues). We have characterized the non-extractable residues of highly polluted riverine sediments (Spree River, Teltow Canal, Germany) in order to investigate the occurrence, alteration and distribution of several organic xenobiotics in situ, e.g. plasticizers, pesticides, and metabolites brominated and chlorinated aromatics, fragrances, technical additives and nitro compounds. Therefore this study intended a comprehensive characterization of riverine MOM combining different analytical techniques (pyrolytic analyses and chemical degradation techniques), in order to provide information concerning the incorporation mechanism and the mode of binding of a variety of organic pollutants with different chemical properties.

Due to their lipophilic properties, dioxins can be integrated in the lipidic vacuole of adipocytes (fat cells). The aim of this study was to determine the kinetics of incorporation and release of H-labelled palmitic acid and C-labelled 2,3,7,8-TCDD in isolated adipocytes from pigs. The incorporation of 2,3,7,8-TCDD and palmitic acid was found to be concomitant in conditions of lipogenesis, under the effect of increasing quantities of insuline and in presence of glucose. The release of these two compounds was found to be dependant of a lipolytic agent (adrenalin). These results suggest the risk of an strong increase of 2,3,7,8-TCDD in blood induced by lipolysis for animals or humans previously exposed to this dioxin.

Organic and inorganic halogenated by-products are generally formed when chlorine is used for surface water potabilisation. The main halogenated by-products relevant for drinking water production are trihalomethanes and bromate anion. Strategies to control and reduce such by-products in drinking water are presented and discussed. Replacing chlorine with ozone and removing natural organic matter on granular activated carbon (GAC) filters reduces trihalomethanes. Acidic pH reduces the formation of bromate anion when ozone is used for disinfection. By combining these strategies and operating them at an industrial level for surface water treatment, drinking water with excellent bacteriological quality and low halogenated by-products is produced and supplied to the customer.

The concentrations of particle-bound organic compounds comprising -alkanes, -alkanoic acids, polycyclic aromatic hydrocarbons (PAH) and nitrated polycyclic aromatic hydrocarbons (NPAH) in ambient air of Algiers city area, were measured from May 1998 to February 1999. Motor vehicle were found to be the main source of airborne particles in downtown Algiers, while combustion and bacterial activity seemed to be responsible of the air pollution at the Oued Smar waste landfill. The in-situ generation of some NPAH seemed to contribute to air pollution, especially during summertime. In general, the wintertime concentrations of the organic pollutants in Algiers were similar to those measured in Europe, especially over the Mediterranean Basin. The chemical characterisation of organic compounds in smoke particulate matter emitted from fats and bitumes industries were also investigated and revealed specific distribution profiles of -alkanes, -alkanoic and -alkenoic acids, and PAH.

A general solution of coupled diffusion-reaction equations governing the spatial and temporal evolution of an arbitrary number of inter-reacting air pollutants has been developed. Although the present reaction chemistry is just limited to gas-phase pseudo-first-order process, the solution is of use to determine the reaction rate constants of complex reaction paths consisting of successive-, reversible-, cyclic-, and concurrent-reaction. Transport parameters (diffusion and advection) of the air pollutants are also involved in this solution. Moreover, equilibrium concentrations (or number densities) of all the air pollutants can be determined using a dynamic equilibrium solution (steady state solution) derived from the balance condition between their transport and reaction processes. For an appropriate model analysis, we have examined a toluene chemistry model that comprises ten related chemicals with twenty-six reaction rate constants under normal urban area conditions.

Laser desorption-ionisation/time-of-flight mass spectrometry (LDI/TOF MS) and liquid chromatography/atmospheric pressure chemical ionisation-ion trap mass spectrometry (HPLC/APCI-ITMS) were used for the analysis of polycyclic aromatic hydrocarbons with molecular weight exceeding 278 Da (HMW-PAHs) in air, water and soil samples from the contaminated area of DEZA chemical plant, Valašské Mezříčí, Czech Republic, and from its vicinity. Semipermeable membrane devices (SPMDs) were employed for passive sampling. LDI-TOF MS proved to be a suitable method for quick evaluation of the HMW-PAHs distribution; the presence of PAHs with molecular mass exceeding 500 Da in real samples was proved by this method. Identification and quantitation of individual PAHs was realised using LC/APCI-ITMS. LDI-TOF mass spectra and selected LC/APCI-MS profiles (/ 303, 327 and 351) were used to confirm the source of contamination by high-molecular-weight PAHs in this area.

In Europe, Alpine valleys represent one of the most important crossroads for heavy traffic. The vehicle impact on air quality is not well-known due to a lack of data in valley systems. Besides a health toxicity concern, the study of atmospheric polycyclic aromatic hydrocarbons (PAHs) is of geo-chemical interest because they are emitted mainly by combustion processes. This class of compounds is also particularly interesting for the study of the potential impact of heavy duty traffic on air pollution. PAHs are therefore actually regarded as priority pollutants of our air environment. As part of the program "Pollution des Vallées Alpines” (POVA), we performed two sampling surveys of PAHs in two sensitive valleys: the valley of Chamonix and the valley of Maurienne. In each valley, two sites were instrumented for atmospheric PAH sampling, and for others pollutant monitoring such as NO, ozone, and particulate matter (PM10). The first sampling campaign was performed in summer 2000 and the second in winter 2001 both periods occurring during the corresponding closure of the Mont Blanc tunnel. During both seasons the total particulate PAH concentrations were higher in the valley of Chamonix despite the stop of international traffic through the Chamonix Valley. In summer, the average total PAH concentration was nearly twice as high in the Chamonix Valley (1.3 ng m) than in Maurienne Valley (0.8 ng m). In winter the difference between the two valleys is larger since the average PAH concentrations reached 48 ng m and 18 ng m in Chamonix and Maurienne Valley, respectively. In addition PAH total concentration reached very high levels (155 ng m) in the valley of Chamonix especially during anticyclonic periods. This very sharp increase of the PAH concentrations can be connected to an increase of the emissions in winter.

To evaluate the risk of PAHs and dioxins transfer to humans several studies on dairy ruminant exposure and on intestinal absorption have been conducted. In order to assess PAHs feed-milk transfer, the transfer of three C-labelled PAHs (C-phenanthrene, C-pyrene, C-benzo[a]pyrene) and C-2,3,7,8-TCDD has been studied after a single oral ingestion (2.6 × 10 Bq) to lactating goats. Radioactivity associated to the labelled PAHs and 2,3,7,8-TCDD has been detected in milk seven hours after the molecules administration. Cumulated part of ingested radioactivity recovered in milk after five days have reached a similar level after 103 h for C-phenanthrene and C-pyrene (1.5% and 1.9% respectively). C-benzo[a]pyrene did not appear significatively in milk (0.2% of ingested radioactivity). Transfer of C-2,3,7,8-TCDD to milk was higher than for PAHs, reaching 7.8% of ingested radioactivity. The bioavailability of PAHs and dioxins was assessed using two animal models. In one hand, we have characterized the in-vitro transfer of PAHs and dioxin through intestinal barrier using Caco-2 cells cultivated on permeable filters. In the other hand, we have described the specific arterial apparition profile of the studied micropollutants in growing pig. The in-vitro experiment showed that C-pyrene, C-phenanthrene, C-benzo[a]pyrene and C-2,3,7,8-TCDD were able to cross the intestinal barrier. C-phenanthrene was transported 1.1-, 1.8-, and 6.7-folds more than respectively C-pyrene, C-benzo[a]pyrene and C-2,3,7,8-TCDD after 6 h exposure. Regarding arterial apparition profiles, C arterial level from C phenanthrene was about 3 and 10 times more elevated than C level from C-benzo[a]pyrene and C-TCDD respectively. These results can be related to the intestinal barrier transfer profile of the same molecules. The results presented in this paper contribute to give new insights on evaluation of the risk of PAHs and dioxins transfer to humans via the dairy ruminant. They particularly clarify the way by which organic micropollutants are transferred to milk and to living organisms during digestion and absorption.

Polycyclic aromatic hydrocarbons (PAHs) are of particular interest because of their potential toxic and carcinogenic properties. Due to their low water solubility and their high affinity for organic matter, PAHs are easily concentrated in sewage sludge and may contribute to the contamination of agricultural soils by spreading. In this study, the behavior of 13 PAHs was assessed during anaerobic and aerobic mesophilic treatments of naturally PAH-contaminated sewage sludge. It was shown that abiotic losses were strictly limited to the light PAHs, e.g. fluorene, phenanthrene and anthracene. Under methanogenic conditions, PAH removal was about 50% whatever PAH molecular weight. More specifically, PAH removal was closely linked to solids reduction implying limitation by bioavailability. Under aerobic conditions, the aerated process enhanced PAH removal up to 90%. In contrast, the aerobic treatment is more efficient than the anaerobic treatment to remove PAHs from contaminated sludge by favoring the PAH diffusion. Moreover, the aerobic process was successful for sludge decontamination because outlet concentrations in dry weight were lower than actual French required values, for fluoranthene and benzo[b]fluoranthene.

Photodegradation of 1% weight ratio pyrene on different model supports SiOCaCO and montmorillonite was investigated. The kinetic studies show that the pyrene pseudo half-lives depend on the nature of the support, and on the presence of water: on dry support, = 3 h on SiO, 3 h on CaCO, and 6 h on montmorillonite whereas, in presence of water, = 9.9 h, 9.9 h, and 221 h, respectively. The irradiation of pyrene revealed degradation products such as 1-hydroxypyrene, 4,5-dihydro-4,5-dihydroxypyrene, 1,6 and/or 1,8-dihydroxypyrene, 1,6 and/or 1,8-pyrenequinone and 1,1′-bipyrene. Given the byproducts identified, the inhibition of pyrene transfer S→T with HgCl and an oxidation non photosensitized by rose bengal, a possible degradation pathway is proposed which involves the formation of a pyrene radical cation via the singlet state of pyrene.