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Paper product manufacturing involves a variety of chemicals used either directly in paper and pulp production or in the conversion processes (i.e. printing, gluing) that follow. Due to economic and environmental initiatives, paper recycling rates continue to rise. In Europe, recycling has increased by nearly 20% within the last decade or so, reaching a level of almost 72% in 2012. With increasing recycling rates, lower quality paper fractions may be included. This may potentially lead to accumulation or un-intended spreading of chemical substances contained in paper, e.g. by introducing chemicals contained in waste paper into the recycling loop. This study provides an overview of chemicals potentially present in paper and applies a sequential hazard screening procedure based on the intrinsic hazard, physical–chemical and biodegradability characteristics of the substances. Based on the results, 51 substances were identified as potentially critical (selected mineral oils, phthalates, phenols, parabens, as well as other groups of chemicals) in relation to paper recycling. It is recommended that these substances receive more attention in waste paper. [ABSTRACT FROM AUTHOR]

In this work the influence of different surfactants and their mass fractions on the optical characteristics of office papers, made from recycled fibres and mixed sources, was examined. Sodium lauryl ether sulfate, cocamidopropyl betaine and fatty alcohol etoksylate like surface active agent were used. The reflective spectra of treated papers were measured before and after accelerated ageing. The results have shown that fibres origin and amount of fillers in paper structure have the most important influence on reflectance spectra. Accelerated ageing has the most significant influence on virgin fibres, while this influence is decreased in office papers. Surface active agent molecules adsorbed on virgin fibres stabilise filter paper during electromagnetic radiation while this stabilisation is significantly reduced for office paper with more complex structure. Chemical composition of paper fillers and surface active agents has important influence on stabilisation possibility of office paper during accelerated ageing. [ABSTRACT FROM AUTHOR]

The sources of environmental pollution in process industries in Bangladesh are discussed. Total pollution load into environment (i.e., into air, water and land) generated from process industries is determined and presented using industrial pollution projection system (IPPS) developed by the World Bank. Most polluting industries in Bangladesh are identified and ranked. The projection of this pollution load for year 2011-2012 is estimated and discussed. It was found that the food industry was the worst air polluter, whereas pulp and paper was the worst water polluter, and tanneries and leather industries were worst polluter of toxic chemicals. Industrial pollution control measures are recommended. [ABSTRACT FROM AUTHOR]

This paper describes an efficient kinetic resolution process of trisubstituted cyclic olefins via a chiral dioxirane generated in situ from a fructose-derived ketone and Oxone. The substrates presented include a variety of 1,3-disubstituted and 1,6-disubstituted cyclohexenes with the stereogenic centers at allylic positions. A sequential desymmetrization and kinetic resolution of 1,4-cyciohexadienes by the chiral dioxirane was also found to be feasible. The initially formed monoepoxides can be kinetically resolved by continuing the reaction, leading to the increase or decrease of the ee values of monoepoxides depending on the diene systems. In some cases, a prochiral directing group is not required and the first formed epoxide stereoselectively directs the second epoxidation. When the coupled desymmetrization and kinetic resolution is used synergistically, high enantiopurity can be obtained for an epoxide from an intrinsically less enantioselective substrate. The observed absolute and relative stereochemistry as well as the changing optical purity can be effectively rationalized by transition state analysis. [ABSTRACT FROM AUTHOR]

Features a study that examined the susceptibility of printed paper to attack of chewing insects after gamma irradiation and ageing. Effects of irradiation on the mechanical and chemical characteristics of paper; Types of paper used in the experiment; Relationship between the gamma dose absorbed by the paper and the erosion caused on it by the chewing insect.

Smoothness is an important factor in consumer perception of tissue quality, with physical modification and chemical additions to the paper able to enhance tissue handle. Therefore objective measurement of the papers mechanical properties in developing new products and maintaining existing quality is vital. In this study the surface chemical composition of the softener treated paper is investigated using ToF-SIMS, and related to the surface frictional properties of the paper. [ABSTRACT FROM AUTHOR]

We conducted an evaluation of shredded paper insulation to identify potentially toxic components. The study was to provide a preliminary characterization of a few samples of insulation currently in use. The following samples were analyzed: previously produced insulation (PPI) containing fire retardants, shredded recycled paper (PPI feedstock), freshly produced insulation (FPI), and insulation which had been installed in a residence (II). Volatile constituents were analyzed by GC-MS from headspace air of samples held at room temperature or heated to 90 C. Extractable constituents were sampled by extracting with methylene chloride, and analyzing by GC-MS. Formaldehyde analysis was done according to EPA Method TO11. Headspace air at room temperature contained no detectable quantities of volatile constituents for any sample measured. In headspace air at 90 C, only PPI contained traces of aliphatic and aromatic hydrocarbons and higher aldehydes, and FPI traces of toluene. Extracts of PPI contained traces of octadecadienoic acid methyl ester and aliphatic and aromatic hydrocarbons and higher aldehydes. Extracts of PPI feedstock contained traces of a substituted cyclohexenecarboxylic acid. FPI contained extractable diethyl phthalate (30-50 mu g/g). Extracts of II contained traces of methyl palmitate, an octadecenoic acid methyl ester, and a phthalate plasticizer. No formaldehyde was detected. PPI was composed of approximately 98 percent paper fiber and 2 percent pre-gelatinized starch. PPI samples agglomerated together with less than 0.01 percent separating from clumps as fine dust. Boron and sodium were expected and confirmed because they were added to PPI and FPI as fire retardants. Chromium, copper, iron, potassium, magnesium, manganese, phosphorus, and silicon were present at detectable concentrations. Study calculations indicate that an occupant would have to completely consume all the fine particles produced from 3.3 kg of insulation per day to have an intake of boron equivalent to the EPA RfD. No other constituent appeared to be present even close to toxicologically relevant amounts. [ABSTRACT FROM AUTHOR]

The article presents a study which identifies the exposure of comparative toxicity in earthworms Eisenia fetida and Lumbricus terrestris to cadmium nitrate. Researchers used artificial soil and filter paper protocols in conducting the comparative toxicity in earthworms. The manure worm, Eisenia fetida, is criticized for not being sufficiently sensitive to chemicals or representative of typical earthworms. It was indicated that dry mass-based LD50s enable direct comparison between exposure protocols as well as species.

The article focuses on the use and risks in books and artifacts of the chemical thymol. It states that thymol vapors have long been used to manage fungus infections in cultural property, particularly books and works of art on paper. When books are at risk because of high moisture level exposure, the insertion of thymol impregnated papers between the pages has been proposed. Also, the chemical is used to retard mold growth in starch pastes and in treatment procedures involving prolonged levels of high humidity. In recent years, however, such applications of thymol have been questioned on the grounds of risk to the artifact itself, danger to the conservator responsible for the treatment, and the uncertain effectiveness of the treatment.

The article reports on the opportunity in the paper coating industry in relation to specialty chemicals. It notes that the market for specialty chemicals used for paper production is worth 16 billion dollars in which the sales is attributed to coating chemicals. It adds that the largest market for specialty paper chemicals is in Western Europe. It also cites that paper coatings are intended for a specific function and paper type.