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PubMed2003

Application of toxicity tests into discharges of the pulp-paper industry in Turkey.

The aim of this study was to investigate the acute toxicity of pulp-paper industry wastewater using traditional and enrichment toxicity tests and to emphasize the importance of toxicity tests in wastewater discharge regulations. Enrichment toxicity tests are novel applications and give an idea of whether there is potential toxicity or growth-limiting and -stimulating conditions. Different organisms were used such as bacteria (floc and coliform bacteria), algae (Chlorella sp.), protozoa (Vorticella sp.), and fish (Lepistes sp.) to represent four trophic levels. Furthermore, chemical oxygen demand (COD) fractionation results were compared with these tests to assess the effect of COD subcategories on the determination of possible toxicity. The pulp-paper industry results revealed acute toxicity to at least two organisms in 6 of 20 effluent samples. The toxicity test results were assessed with chemical analyses such as COD, biochemical oxygen demand (BOD), color, absorbable organic halogen (AOXs), and phenol. It was observed that the toxicity of the effluents could not be explained by using physicochemical analyses in four cases for the pulp-paper industry. The results clearly indicate that bioassay tests provide additional information on the toxicity potential of industrial discharges and effluents.

Animals↗
PubMed2003

Paper patching for chronic tympanic membrane perforations.

OBJECTIVE: This study was designed to evaluate the results of paper-patch myringoplasty in patients with chronic perforations of the tympanic membrane of different sizes. STUDY DESIGN AND SETTING: A retrospective survey of paper-patch myringoplasties performed in a tertiary referral academic medical center on 77 patients with chronic perforations of the eardrum was carried out. Data consisted of the causes of the perforations, time the perforations had been present, their size, number of patch applications, duration of application, and number of successfully closed perforations. RESULTS: Closure rate was 63.2%, 43.5%, and 12.5% for small, medium, and large perforations, respectively. Small perforations needed the least number of repeated applications and the least time for closure. CONCLUSIONS AND SIGNIFICANCE: Paper patching is technically simple, time saving, safe to perform, cost effective, and suitable as an outpatient procedure and has a good success rate, It should be tried in perforations smaller than 5 mm before a patient is referred for surgery.

Adolescent↗
PubMed1988

Determination of mefloquine by electron-capture gas chromatography after phosgene derivatization in biological samples and in capillary blood collected on filter paper.

Mefloquine is determined in 100-microliter samples of whole blood, plasma and capillary blood collected on filter paper by gas chromatography with electron-capture detection after derivatization with phosgene. Sample preparation for whole blood and plasma involves a protein precipitation step that uses a combination of zinc and acetonitrile, followed by simultaneous extraction with methylene chloride and derivatization with phosgene at pH 9.50. Filter paper spots are immersed for 12-24 h in 0.1 M hydrochloric acid, followed by simultaneous extraction with methyl tert.-butyl ether and derivatization. After evaporation of the organic phase and reconstitution with ethyl acetate, 1 microliter of the extract is injected into a megabore capillary column. Because of the high sensitivity of the method, mefloquine concentrations down to 25 nmol/l (9.5 micrograms/l) are determined in 100-microliters samples with a relative standard deviation of 12% at the 25 nmol/l level. Excellent precision was obtained over the range of concentrations tested, 0.10-3 mumol/l (45-1100 micrograms/l), in both plasma and whole blood and from filter-paper-collected capillary blood. The day-to-day relative standard deviation in plasma at the therapeutic level (1-3 mumol/l) was 4.5% (n = 8).

Antimalarials↗
PubMed2001

Influence of the operating conditions in the acetone pulping of wheat straw on the properties of the resulting paper sheets.

A central composite factor design was used to examine the influence of independent variables in the acetone pulping of wheat straw (processing temperature, time, and acetone concentration) on the yield of the resulting pulp, and on various physical properties of paper sheets (breaking length, stretch, burst index, tear index and brightness) obtained from it. Equations that related each dependent variable to the different independent variables were obtained, and these reproduced the experimental results for the yield, breaking, stretch, burst index and brightness obtained at temperatures, times, and acetone concentratons over the ranges 140-180 degrees C, 60-120 min and 40-80%, respectively, with errors less than 20%. Obtaining the optimum breakinig length, stretch, burst index and tear index for the paper sheets (3,456 m, 1.42%, 1.36 kN/g and 3.86 mNm2/g, respectively) entails using a high temperature; the processing time and acetone concentration only influence stretch, optimization of which requires using a short time and a low concentration. The optimum brightness (30.44%) is achieved with a low temperature, a short time and a medium acetone concentration. In order to minimize losses of solvent during its recovery and recycling while ensuring acceptable levels of the properties of the paper sheets, a high temperature, a low acetone concentration and a short time can be used; the brightness level thus obtained is only 10% lower than the optimum value.

Acetone↗
PubMed1995

Comparison of the repair of permanent tympanic membrane perforations by hydrocolloidal dressing and paper patch.

Thirty consecutive patients with permanent perforations of their tympanic membranes (TM) present from 2.5 to 50 years (mean 18.7 years) were admitted to a prospective study using two alternative methods of dressings for closure of the perforations. An adhesive-coated hydrocolloid material was compared with a conventional dressing of vaseline impregnated rice paper patch after de-epithelialization of the perforation border. Nine of the permanent TM perforations (30 per cent), five with the hydrocolloidal dressing and four with the rice paper patch had healed when followed-up after one year. The size of eight of the central perforations that had healed was equal to or less than 25 per cent of the TM. Also one perforation with a size of 65 per cent had healed. Seven perforations were located in the posterior part of the TM: four in the posterior-superior quadrant, one in the inferior quadrant, one had engulfed the posterior half of the TM and one included the anterior-inferior quadrant. Only two perforations out of 14, with a size of 25 per cent or less, located in the anterior-inferior quadrant, healed. No significant difference was demonstrated between the two types of dressings. Both groups noted an immediate improvement in hearing of 10.8 and 9.3 dB, respectively, after application of the dressing. The study demonstrates that application of an occlusive dressing or paper patch in 30 per cent of patients can promote the healing of long-standing perforations. The chances for healing are better if the perforation is located in the posterior part of the TM. This simple technique immediately improved hearing and should be tried before a patient is referred for myringoplasty surgery.

Adolescent↗
PubMed2002

Supercritical fluid extraction of potential migrants from paper and board intended for use as food packaging materials.

The optimization of supercritical fluid extraction using CO2 for the extraction of contaminants in 15 samples of recycled paper and board (P&B) has been studied. An experimental design was used for simultaneous optimization of the variables involved in both the extraction step and the collection of the extract. Methanol was used as modifier. Several plastisizers such as diethyl phthalate, diisobutyl phthalate, di-n-butyl phthalate, dioctyl adipate, and diethylhexyl phthalate (from 2 to 100 microg/g of paper) were found in the recycled P&B samples. A discriminate analysis applied to all results obtained allow us to classify the samples in three different groups according to the content of recycled pulp (0, 10-30, and > 80% of recycled pulp), the sample thickness (from <300 to >600 microm), and the surface treatment of the paper. The analytical behavior and the results are discussed.

Carbon Dioxide↗
PubMed2004

Representativeness of extracts of offset paper packaging and analysis of the main odor-active compounds.

Packagings often carry odors due to the support and printing inks. The aim of the investigation was to define a representative solvent-free extract of paper-based packaging materials printed by the offset process, for the identification of the odor-causing volatile compounds. Static headspace and solid-phase microextraction were the two applied extraction methods. Representativeness tests showed that the odor of the PDMS fiber extract gave satisfying odor similarities with the original packaging. The sample incubation was performed at 40 degrees C for 30 min, whereas the extraction time was 3 min at 40 degrees C. Extracts of both the nonprinted and printed papers of different batches were analyzed by gas chromatography-olfactometry. 4-Phenylcyclohexene was identified as the most potent compound contributing to the latex-like odor of the nonprinted paper. Among the 13 major odorants identified by mass spectrometry, 10 were aldehydes and ketones generated by oxidation of the printing ink resins. The ratio of odorants to interferences was too low for a possible detection of the key odorants by nonseparative techniques such as sensor arrays.

Aldehydes↗
PubMed2005

Photodegradation of substituted stilbene compounds: what colors aging paper yellow?

Photodegradation of lignin is one of the major postprocessing problems in paper production, as this renders yellowing of the paper and reduced paper quality. In this study, we have explored the photochemical properties of substituted stilbene derivatives believed to be key chromophores in the photodegradation of lignin derived from cinnamyl alcohol. In particular, the present work focuses on the computation of UV/vis electronic absorption spectra for different methoxylated stilbenes and their proposed photodegradation products. All calculations were performed using the time-dependent formalism of density functional theory (TD-DFT) and the B3LYP hybrid functional. It is concluded that the methodology employed is capable of reproducing not only the overall spectra, but also subtle features owing to the effects of different substitution patterns. For the strongly absorbing first excited singlet state (HOMO --> LUMO excitation) of the methoxylated stilbenes, the calculated transition energies are, albeit somewhat fortuitously, in excellent agreement with experimental data. The light-induced yellowing indirectly caused by the presence of stilbenes can be rationalized in terms of the absorption spectra of the resulting photodegraded o-quinones, for which distinct transitions in the 420-500 nm region of the visible spectrum lacking prior to degradation are observed.

Absorption↗
PubMedDate not supplied

Canadian environmental effects monitoring: experiences with pulp and paper and metal mining regulatory programs.

In Canada, Environmental Effects Monitoring (EEM) programs exist within two regulations: the Pulp and Paper Effluent Regulations and the new Metal Mining Effluent Regulations under the Canadian Fisheries Act. EEM provides a biological, effects-based feedback loop to assess the effectiveness of technology-based regulations in protecting receiving environments. The promulgation of the Pulp and Paper Effluent Regulations, in 1992, represented a significant step forward in the Canadian regulatory approach by incorporating directly into a regulation a requirement to assess the effects of effluent discharges on receiving environments using proven scientific monitoring methodologies. Similarly, an assessment of the aquatic impacts of mines resulted in recommendations to amend the Metal Mining Effluent Regulations, recently promulgated in 2002, and includes an EEM program as a science-based feedback loop. As such, these regulations recognize the possibility that national, technology-based standards may not necessarily protect all receiving environments because of the diversity and variability of both discharges and receiving sites across the country. Since that time, EEM has improved its flexibility by considering both advances in science and the uniqueness of monitoring sites across Canada to allow the most appropriate and cost-effective monitoring approaches at each site while maintaining national consistency. This paper discusses the use of monitoring under two Canadian regulations to assess effects on aquatic ecosystems. As well, the National EEM approach to maintaining up-to-date scientific practices in a national regulatory program is discussed using examples.

Canada↗
PubMed2004

Physiological changes in largemouth bass exposed to paper mill effluents under laboratory and field conditions.

We report here on studies designed to asses the effects of paper mill effluents on non-reproductive functions of free-ranging and captive Florida largemouth bass (Micropterus salmoides floridanus). This was accomplished by conducting an outdoor tank study, in which fish were exposed to well water or to 10%, 20%, 40%, and 80% full strength effluent for 28 or 56 days, and by sampling largemouth bass from sites within the St. Johns River, Florida, upstream and downstream from a paper mill plant. Blood and plasma samples from fish from the tank study and from fish sampled from the ambient sites were analyzed for over 20 variables. We also determined liver and spleen weights and examined them histologically. The most significant finding from the tank study was an increase in the concentration of albumin and hepatosomatic index for bass exposed to > or = 20% effluents for 56 days. Spleenosomatic index and number of melanomacrophage centers were decreased in bass from effluent-dominated sites (Palatka and Rice Creek), whereas concentrations of calcium, phosphorous, glucose, and creatinine were elevated in fish from these sites, compared to fish from reference streams. Fish from Rice Creek also had fewer red blood cells, and male bass from Palatka had lower concentrations of cholesterol. Plasma concentrations of albumin and hepatic concentrations of glutathione were elevated in males from Palatka, and both females and males from Rice Creek had higher concentrations of globulin. These results indicate a complex pattern of effects of paper mill effluents on several physiological functions. However, despite the myriad of treatment and site-related effects, most physiological parameters fell within normal ranges when compared to reports on largemouth bass and other freshwater species.

Animals↗
PubMed2002

Potential microbiological hazards in the production of refined paper products for food applications.

This study sought to investigate the significance of raw materials (starch-based glues, raw material papers) at different microbiologically critical stages in the manufacturing process of refined paper products. The study examined the occurrence of microorganisms in the process and in end-product samples. Microbiological surveys verified that the production and use of pasteurized starch-based glue was the most important factor threatening the process hygiene and product safety. Subsequently, the production and use of starch-based glue was changed, and a follow-up programme targeting the microbiological quality of glue was developed as part of a hygiene and safety management system. A total of 33 spore-forming bacterial and 15 enterobacterial isolates were ribotyped, and 22 and 10 different ribogroups (ribotypes), respectively, were generated. These isolates from starch-based glue, raw material paper and end products were atypical and, thus, in many cases physiological, chemotaxonomic (FAME) and molecular (partial 16S rDNA) results did not correspond. The most common spore-forming bacteria (55% of the isolates) were Paenibacillus sp. and within this genus several new species were also proposed. The most common enterobacteria (87%) were Enterobacter cloacae and Citrobacter freundii belonging to bacteria in hazard group 2, or species closely related to them. It was demonstrated that the same spore-forming bacteria (ribotypes) were present in both the glue samples and the end products (45% of isolates). All RiboPrint patterns were saved at the VTT identification library for future use.

Adhesives↗
PubMed2002

Structure and on-site formation of biofilms in paper machine water flow.

Paper machine biofilms formed in situ on stainless steel surfaces were studied. A robust flow cell was fitted to side stream (1.8 m s(-1)) of the spray water circuit of a paper machine. This on-site tool allowed for assessing the efficacy of antifoulants and the adequacy of steel polishing under mill conditions. A rapid fluorescence-based assay was developed to quantify the biomass of shallow biofilms on machine steel. The fluorescence matched the ATP content measured for the same biofilms. Electrolytic polishing reduced the tendency of biofouling of 500 grit surface steel. Biofilm grew under machine conditions as clusters on the steels, showing uniformly coccoid, filaments or short rods; only one cell type in each cluster. The biofilm clusters excluded latex beads of 0.02 microm with hydrophilic or with hydrophobic surfaces from penetrating more than three to four layers of cells. Under the high hydraulic flow at the machine (1.8 m s(-1)), the biofilm grew in 7 days 6-10 microm thick. The high flow rate guided the shape of the biofilm clusters emerging after the primary attachment of cells. Adhered individual bacteria were the platform on steel to which solids such as paper machine fines then accumulated.

Bacterial Adhesion↗
PubMed2003

An evaluation of the stability of factor VIII inhibitors in plasma and plasma dried on filter paper discs stored at room temperature.

The transportation of plasma specimens to specialized haemophilia centre laboratories for anti-factor VIII inhibitor titre determination is often necessary. The routine method of transporting frozen specimens on dry ice is limited by its cost and need for special handling. The present study was undertaken to evaluate the effect of storing specimens at room temperature on the FVIII inhibitor titre determinations using the Bethesda assay. Specimens stored both in liquid phase as well as adsorbed onto filter paper discs were studied. The results of the present study demonstrate that plasma specimens stored for up to 2 weeks at room temperature, either in liquid phase or adsorbed onto filter paper, yield equivalent measures of FVIII inhibitor titres using the Bethesda assay to plasma specimens stored frozen at -70 degrees C. Plasma specimens dried on filter paper discs and stored at room temperature offers a reliable, more practical and less expensive alternative to frozen plasma as a means of transport to specialized referral laboratories for analysis of anti-FVIII titres.

Autoantibodies↗
PubMed2003

Identification of aerobic mesophilic bacilli isolated from board and paper products containing recycled fibres.

AIMS: To identify aerobic mesophilic bacteria isolated from coreboard, kitchen roll paper and food packaging boards containing recycled fibres and to create a rapid fingerprint-based database for their identification. METHODS AND RESULTS: A total of 197 isolates and 20 relevant type strains were characterized by automated ribotyping and as far as possible identified by the similarities of their riboprints to the relevant type strains. One strain from each unidentified ribotype, a total of 87 strains, was subjected to partial 16S rDNA sequencing and in most cases also to fatty acid analysis and physiological tests. From the isolates 113 and seven different ribotypes were generated belonging to the genera Bacillus and Paenibacillus, respectively. The dominating species, or closest related to them, were B. simplex (22.8% of isolates), B. licheniformis (18.3%) and B. amyloliquefaciens (12.7%); 5.1% of the isolates were identified as B. cereus, a potential food-borne pathogen. In particular, this species was present in one food packaging board (26.3% of isolates). Based on these results, 40.1% of the isolates and 45.0% of ribotypes were so different from the relevant type strains that they may represent novel species. CONCLUSIONS: All isolates were aerobic spore-formers, indicating that all non-spore-formers were eliminated during the drying stage of the processes. Although many isolates could be affiliated to described species of Bacillus or Paenibacillus, a significant proportion of the isolates could not be identified unambiguously as members of a described species. SIGNIFICANCE AND IMPACT OF THE STUDY: A RiboPrint identification database, composed of 120 composite patters, was established for bacteria originating from the pulp and paper industry. Considering the discrimination power of ribotyping, this database will be extremely useful in future for the reliable and rapid identification of bacteria isolated from pulp and paper industrial sources.

Bacillus↗
PubMed2002

Field evaluation of the CATT/Trypanosoma brucei gambiense on blood-impregnated filter papers for diagnosis of human African trypanosomiasis in southern Sudan.

Most Human African Trypanosomiasis (HAT) control programmes in areas endemic for Trypanosoma brucei gambiense rely on a strategy of active mass screening with the Card Agglutination Test for Trypanosomiasis (CATT)/T. b. gambiense. We evaluated the performance, stability and reproducibility of the CATT/T. b. gambiense on blood-impregnated filter papers (CATT-FP) in Kajo-Keji County, South-Sudan, where some areas are inaccessible to mobile teams. The CATT-FP was performed with a group of 100 people with a positive CATT on whole blood including 17 confirmed HAT patients and the results were compared with the CATT on plasma (CATT-P). The CATT-FP was repeated on impregnated filter papers stored at ambient and refrigerated temperature for 1, 3, 7 and 14 days. Another 82 patients with HAT, including 78 with a positive parasitology, were tested with the CATT-FP and duplicate filter paper samples were sent to a reference laboratory to assess reproducibility. The CATT-FP was positive in 90 of 99 patients with HAT (sensitivity: 91%). It was less sensitive than the CATT-P (mean dilution difference: -2.5). There was no significant loss of sensitivity after storage for up to 14 days both at ambient and cool temperature. Reproducibility of the CATT-FP was found to be excellent (kappa: 0.84). The CATT-FP can therefore be recommended as a screening test for HAT in areas where the use of CATT-P is not possible. Further studies on larger population samples in different endemic foci are still needed before the CATT-FP can be recommended for universal use.

Agglutination Tests↗
PubMed2005

Safety assessment of paper and board food packaging: chemical analysis and genotoxicity of possible contaminants in packaging.

In order to identify potential genotoxicant(s) in recycled paperboard, samples were fractionated using multiple liquid/liquid extraction, and gel permeation chromatography, and analysed by gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry. The rec-assay was used as an indicator of genotoxicity. Genotoxicants in the recycled paperboard were identified as dehydroabietic acid (DHA) and abietic acid (AA). DHA and AA were detected in two out of five virgin products, and in all seven recycled products for food-contact use. Total amounts of DHA and AA were 240 and 990 microg/g in the virgin products and 200-990 microg/g in the recycled products. A good correlation was observed in the total amount of DHA and AA content determined in paper products and DNA-damaging activity. Moreover, genotoxic effects in paper products showed a good match with standard compounds, indicating that the genotoxic effects of these paper products was mostly attributable to DHA and AA.

Abietanes↗
PubMed2007

Oestrogenicity of paper and cardboard extracts used as food containers.

Bisphenol-A (BPA), dibutyl phthalate (DBP), and di-2-ethylhexyl phthalate (DEHP), which are common chemical residues in food-packaging materials, were investigated in paper and cardboard containers used for take-away food. The oestrogenicity of aqueous extracts was tested in E-Screen bioassay and analysis carried out by high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC/MS). Oestrogenicity was demonstrated in 90% of extracts (geometric mean [GM] = 11.97 pM oestradiol equivalents g(-1)). DEHP, DBP, and BPA (GM = 341.74, 37.59, and 2.38 ng g(-1) of material) were present in 77.50, 67.50, and 47.50% of samples, respectively. In bivariate analyses, no significant association was found between the levels of these chemicals and oestrogenicity in cardboard/paper extracts. A close-to-significant association was found between oestrogenicity and DBP (beta = 1.25; p = 0.06) in paper extracts, which reached statistical significance in multivariate analysis (beta = 1.61; p = 0.03). Paper and cardboard used in food packaging may contribute to the inadvertent exposure of consumers to endocrine-disrupting chemicals.

Benzhydryl Compounds↗
PubMedDate not supplied

Migration of mineral hydrocarbons into foods. 4. Waxed paper for packaging dry goods including bread, confectionery and for domestic use including microwave cooking.

Retail samples of dry goods (bread, biscuits and breakfast cereals) packaged in waxed paper were examined for the presence of mineral hydrocarbon wax. Bread loaves contained up to 50 mg/kg of the wax (associated with the outer surfaces) and crackers up to 185 mg/kg. Mineral oil was found in bread samples, at up to 550 mg/kg and was dispersed throughout indicating its use in food processing machinery as the likely source. Retail confectionery products wrapped in waxed paper (containing 12-44% w/w) gave rise to levels of 12-1300 mg/kg mineral hydrocarbon in the individually wrapped sweets. Migration into boiled sweets was lowest at 10-130 mg/kg, whilst soft chews and toffee products contained 110-1300 mg/kg. The distribution of wax hydrocarbons (principally n-alkanes) in the confectionery coincided exactly with that for the paper wrapping, with a range of C23 to C33 (95% material) centred around C26. This indicated that the transfer to the food occurred largely by adhesion rather than by diffusion since the latter would be expected to favour preferential migration of the low molecular weight components. In simulated home-use experiments with waxed bags sold in the United States for domestic use, migration into sandwiches and cake amounted to 40 mg/kg (1% transfer of wax). Use of these waxed bags in the microwave oven (as recommended) gave rise to contamination of foods from 210 to 1650 mg/kg (up to 60% transfer of wax).

Bread↗