Statistical analysis and isotherm study of uranium biosorption by <Emphasis Type="Italic">Padina</Emphasis> sp. algae biomass

Introduction  

The application of response surface methodology is presented for optimizing the removal of U ions from aqueous solutions using Padina sp., a brown marine algal biomass.     

Spectrofluorimetric study of the ageing of mixtions used in the gildings of mediaeval wall paintings

Introduction  

In the Middle Ages, we could find gildings on mural paintings. Gold, silver or tin leaves were applied according to distemper or mixtion technique. For the first one, a binder as glue is necessary, and for the second, a lipidic binder is used to stick the metallic leaf. Studies of gildings materials characterization show that the mixtion technique, with a mordant, is the most common. Linseed oil seems to be the binder used. It is always mixed with a siccative agent as lead. Because of bad conditions of conservation, the gildings do not resist anymore, only remain traces of metal or the adhesive under-layer. Thanks to the binder fluorescence, we can nowadays detect ancient gildings.     

Polyfluorinated surfactants (PFS) in paper and board coatings for food packaging

Introduction  

In this study, we explore the identity of a range of polyfluorinated surfactants (PFS) used for food contact materials, primarily to impart oil and water repellency on paper and board. PFS are of interest, as they can be precursors of poly- and perfluorinated alkyl substances (PFAS), of which several are persistent and are found worldwide in human blood and in the environment.     

Sustainable development of deep-water seaport: the case of Lithuania

Introduction  

In 2003, the Japan International Cooperation Agency carried out a development feasibility study of Klaipeda Seaport (Lithuania). The focus in this study was the evaluation of environmental impacts of the port expansion because it is located in an ecologically sensitive area. While the Japanese researchers focused on the environmental impact analysis, they did not provide unambiguous conclusions. The problems remained unresolved and required further, more detailed consideration and deeper analysis.     

Size-exclusion chromatographic study of ECF and TCF softwood kraft pulp bleaching liquors

Background, aims, and scope  

Currently, elemental chlorine-free (ECF) and totally chlorine-free (TCF) bleaching systems are widely used for pulp production. Low and medium molecular weight lignin break-down products are known to have harmful effects on the environment. According to some recent results, also high molecular weight (HMW) material consisting mainly of lignin and carbohydrates may cause toxic effects to the environment. For these reasons, toxicity and structure studies of HMW materials are of great importance. This investigation is a part of a larger project to obtain more structure information of HMW materials and toxicity of ECF and TCF bleaching effluents. Size-exclusion chromatography (SEC) has been commonly used for the characterization of organic macromolecules such as lignin, but to our knowledge, no reports have appeared dealing with the comparison of SEC of ECF and TCF bleaching liquors. The aim of the present study was to get more information about the molecular weight distribution (MWD) of HMW fractions of waste liquors from ECF and TCF bleaching sequences by SEC.     

Uptake and distribution of metals by water lettuce (<Emphasis Type="Italic">Pistia stratiotes</Emphasis> L.)

Background, aim and scope  

Water quality impairment by heavy metal contamination is on the rise worldwide. Phytoremediation technology has been increasingly applied to remediate wastewater and stormwater polluted by heavy metals.     

Occurrence of perfluorinated organic acids in the North and Baltic seas. Part 1: distribution in sea water

Purpose  

Due to their high water solubilities and mobilities, persistent, polar perfluorinated compounds (PFCs) such as perfluorinated carboxylates and sulfonates are likely to end up in the oceans. In part 1 of this study, their distribution in North and Baltic Sea water is reported, being of special interest because these seas are surrounded by highly industrialized countries with high population densities.     

The human sex odds at birth after the atmospheric atomic bomb tests,after Chernobyl,and in the vicinity of nuclear facilities

Background, aim, and scope  

Ever since the discovery of the mutagenic properties of ionizing radiation, the possibility of birth sex odds shifts in exposed human populations was considered in the scientific community. Positive evidence, however weak, was obtained after the atomic bombing of Japan. We previously investigated trends in the sex odds before and after the Chernobyl Nuclear Power Plant accident. In a pilot study, combined data from the Czech Republic, Denmark, Finland, Germany, Hungary, Norway, Poland, and Sweden between 1982 and 1992 showed a downward trend in the sex odds and a significant jump in 1987, the year immediately after Chernobyl. Moreover, a significant positive association of the sex odds between 1986 and 1991 with Chernobyl fallout at the district level in Germany was observed. Both of these findings, temporality (effect after exposure) and dose response association, yield evidence of causality. The primary aim of this study was to investigate longer time periods (1950–2007) in all of Europe and in the USA with emphasis on the global atmospheric atomic bomb test fallout and on the Chernobyl accident. To obtain further evidence, we also analyze sex odds data near nuclear facilities in Germany and Switzerland.     

Fine particulate phase PAHs in ambient atmosphere of Chennai metropolitan city,India

Background  

Airborne fine particulates (PM 2.5) and its associated polycyclic aromatic hydrocarbons (PAHs) are reportedly hazardous in urban environment due to the presence of multiple emission sources.     

A preliminary investigation of the environmental impact of a thermal power plant in relation to PCB contamination

Purpose

The most significant application of polychlorinated biphenyls (PCBs) is in transformers and capacitors. Therefore, power plants are important suspected sources for entry of PCBs into the environment. In this context, the levels and distribution of PCBs in sediment, soil, ash, and sludge samples were investigated around Seyitömer thermal power plant, Kütahya, Turkey. Moreover, identity and contribution of PCB mixtures were predicted using the chemical mass balance (CMB) receptor model.

Methods

United States Environmental Protection Agency methods were applied during sample preparation, extraction (3540C), cleanup (3660B, 3665A, 3630C), and analysis (8082A).

Results

ΣPCB concentrations in the region ranged from not detected to 385 ng/g dry weight, with relatively higher contamination in sediments in comparison to soil, sludge, and ash samples collected from around the power plant. Congener profiles of the sediment and soil samples show penta-, hexa-, and hepta-chlorobiphenyls as the major homolog groups. The results from the CMB model indicate that PCB contamination is largely due to Clophen A60/A40 and Aroclor 1254/1254(late)/1260 release into the sediment and sludge samples around the thermal power plant.

Conclusions

Since there are no other sources of PCBs in the region and the identity of PCB sources estimated by the CMB model mirrors PCB mixtures contained in transformers formerly used in the plant, the environmental contamination observed especially in sediments is attributed to the power plant. Release of PCBs over time, as indicated by the significant concentrations observed even in surface samples, emphasizes the importance of the need for better environmental management.