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The present paper initially discussed chemical structures and properties of the dioxins (polychlorinated dibenzo--dioxins or PCDDs) and furans (polychlorinated dibenzo--furans or PCDFs). Also, presents information concerning the sources and origins of PCDDs/PCDFs. A detailed discussion on the emissions of dioxins from incinerators and in particular, their formation in MSW incinerators. The final section of the paper mention approaches to dioxin minimisation during incineration.

This work summarizes brominated flame retardant research in the Ebro River basin. Within a monitoring program at different risk zones in this river, two high-contaminated areas were detected. The first one is located along the Cinca River, a tributary of Ebro River, downstream a heavily industrialized town (Monzón), and data showed a high HBCD contamination in this area. The second one is located along the Vero River, a tributary of Cinca River, downstream an industrial park in Barbastro. In this case, high contamination of deca-BDE-209 was found. Our work included the analysis of sediments and biota, with special attention on aspects such as temporal trends, bioavailability and bioaccumulation of these contaminants. Moreover, an attempt of identification of source contamination was carried out, with the analysis of industrial effluents. In both cases, the industry responsible of the contamination was identified.

PCDDs and PCDFs levels exceeding the European Union tolerance limits were detected in milk from different animal species (cows, sheep, goats, and buffaloes) and in animal feed samples from Campania region in southern Italy. A monitoring plan was performed in the period 2002–2004 to investigate the extension of the contamination. A total of 595 milk samples were analyzed and the percentage of noncompliant samples (PCDD/Fs > 3 pg WHO-TEQ/g fat) was 27% (maximum value 30.43 pg WHO-TEQ/g fat for a sheep's milk). The number of tested feedingstuffs was 434 but only feed likely grown in the area of sampling such as grass, silage and hay (267 samples) showed a significant contamination with 13% of samples containing PCDD/F > 0.75 ng WHO-TEQ/kg product (tolerance limit referred to 12% moisture content). The spatial autocorrelation analysis based on the calculation of the I-Moran index gave significant values for both milk and animal feed and highlighted an area characterized by a widespread practice of illegal waste dumping and burning. The problem of waste management in the area of study is particularly worrying from the sanitary point of view with a significant excess of cancer mortality and occurrence of malformations revealed by a recent research.

Background soils (̃230 samples) were analyzed for DDT and its derivatives to determine the distribution of these compounds on a global scale. Total concentrations of DDT and its metabolites (∑DDTs) ranged over four orders of magnitude, from <0.01 to 426 ng g dry weight and correlated poorly with soil organic matter content (SOM%) and latitude. The average composition of soil residues was similar in the Northern and Southern hemispheres and followed the order: DDT > DDE > DDD. The fraction F = ′-DDT/(′-DDE + ′-DDE) averaged 0.60 ± 0.30, or an average ′-DDT/′-DDE ratio of 1.5. Soil-to-air fluxes of DDT compounds were measured at an experimental farm in Ontario, Canada, where DDT was last applied more than three decades ago. Results showed that agricultural soils are still a significant source for emission of DDTs to the atmosphere. DDT compound ratios in air can be used to distinguish fresh applications from soil emissions, but fractionation of the DDTs occurs during volatilization. The ratio of ′-DDT/′-DDE in air over soil can be predicted from soil residues, assuming that their volatilities are in a direct relation to liquid-phase vapor pressure (P). Results at the Ontario farm and at other farms in Canada and the USA where soil—air exchange studies have been done showed that P was a better predictor for F than K.

The partition coefficients for OCs at typical temperatures in Antarctica and Southern Ocean are calculated and they are used to estimate the partitioning of the OCs between atmospheric particulates and gas phase, scavenging the OCs from gas phase by snow, atmospheric persistence of the OCs, the direction and strength of air/seawater, air/snow, air/soil, and seawater/sediment fluxes for the OCs in Antarctica. The air/soil and seawater/sediment fluxes of OCs are agreed with “cold condensation” hypothesis. The deep water formation in Weddell and Ross Seas, the shelf sediments and the Antarctic snowpack would be important sinks for the OCs.

Clays and “anionic clays” are layered natural and synthetic compounds, respectively, with very special surface properties. Clay minerals are composed of negatively charged aluminosilicate layers whose surface charge is balance by hydrated inorganic cations located in the interlayer space. Smectites are a clay mineral group having swelling or expandable structure which makes the interlamellar space accessible for cationic or polar organic molecules. Anionic clays are positively charged layered double hydroxides (LDHs) where the surface charge is balanced by hydrated inorganic anions in the interlayer space. LDHs have a particularly interesting property, i.e., when heated at 500°C a mixed oxide is formed, which rehydrates in aqueous solution with reconstruction of the original LDH-layered structure. Clay minerals and LDHs are important adsorbents for ionic, ionizable and highly polar organic chemicals because of their charge characteristics and hydrophilic character of their surfaces. In this paper, examples of interactions of these materials with organic molecules are presented. Furthermore, replacement of the inorganic interlayer ions by organic ones has been shown to change the nature of the surface of clays and LDHs from hydrophilic to hydrophobic, increasing the affinity of these minerals for hydrophobic organic compounds. The selective modification of clay minerals with organic cations containing appropriate functional groups is a novel technique to maximize the affinity of the adsorbent for a given chemical. Clays and LDHs modified with organic ions can be used as adsorbents for diverse target molecules.

In this paper an overview is provided of adsorption processes of representative persistent organic pollutants (POPs), in particular atrazine, alachlor and - and -chlordane pesticides with endocrine disruptor activity, by humic acids (HAs), the most abundant and chemically and biochemically active fractions of humified natural organic matter in soil. Endocrine disruptor compounds (EDCs) are hormone-like substances able to alter, i.e., disrupt, the normal endocrine functions in animals and humans. The estrogenic risk of EDCs is generally related to their distribution and speciation in the various soil phases, in which adsorption processes play a very important role. Adsorption kinetics of atrazine and adsorption isotherms of atrazine, alachlor and - and -chlordane onto HA samples isolated from various soil sets were determined using a batch equilibrium method and the HPLC technique with various detectors. Adsorption of atrazine onto HAs occurs rapidly within the first 4 h of contact. Experimental adsorption data were best fitted in a linear isotherm or a nonlinear, L-shaped Freundlich isotherm for atrazine, a linear isotherm for alachlor, and a nonlinear, S-shaped isotherm for - and -chlordane. Thus, no limiting adsorption is observed for any pesticide adsorbate onto any HA sorbent examined over the concentration range tested. In general, the adsorption capacity of HAs for chlordane is much larger than that for atrazine and alachlor, which are adsorbed at almost the same extent by HAs. The carboxylic and phenolic hydroxyl group content, the organic free radical concentration, and the aromaticity and humification degrees appear to be the most important chemical properties of HAs affecting atrazine adsorption, whereas it is not clear which compositional, structural and functional features of HAs may affect adsorption of alachlor and chlordane.

There are eight “hot spots” polluted with PCB identified in the territory of Kazakhstan. The volume of the PCB-containing equipment is approximately estimated at 980 t, and the total volume of wastes is 250,000 t. A populated area Ablaketka suburb, a part of Ust-Kamenogorsk city polluted with PCB due to the former activities of the Ust-Kamenogorsk Capacitor Plant, was chosen as exemplary in order to assess the threat of the PCB pollution to the health of the population. The research does not exclude a possibility of PCB impact on the exposed population.

Republic of Moldova POPs problem is determined by chlorineted pesticide and polychlorinated biphenyls (PCBs) and linked to their use in the past. Scientific studies brought out direct negative impacts of excessive pesticide application, as well as of uncontrolled use of PCBs, on both environment health and on human health. It is concluded that there is an urgent necessity to create a comprehensive chemical safety management system in Republic of Moldova and completely to put into practice the National Implementation Plan for the Stockholm Convention on Persistent Organic Pollutants.

We demonstrate that at reactionary conditions of the growth of nanostructures of different substances can be by-products of most incredible on composition, structure, and morphology objects. Two main innovations are presented in this article. (i) Novel molecular crystals of transparent carbon in the shape of isotropic and anisotropic (thread-like) micro particles (by diameter more 5 mkm) are presented first. Many transparent carbon threads are painted in various colors. (ii) We believe nanochemistry is thescience mostly about nanochemical objects which the properties depend on their size, morphology and structure. Different nanoobjects as nanophases can be the subject also of nanochemistry but as it high border. A new mechanism common for carbon nanotubes, onions and fullerenes formation by hydrocarbons molecules conversations is proposed.