Search results for "Chlorin"
showing 10 items of 374 documents
Effect of solid waste landfill organic pollutants on groundwater in three areas of Sicily (Italy) characterized by different vulnerability
2017
The aim of this study was to obtain information on the presence and levels of hazardous organic pollutants in groundwater located close to solid waste landfills. Eighty-two environmental contaminants, including 16 polycyclic aromatic hydrocarbons (PAHs), 20 volatile organic compounds (VOCs), 29 polychlorinated biphenyls (PCBs), 7 dioxins (polychlorinated dibenzo-p-dioxins, PCDDs) and 10 furans (polychlorinated dibenzofurans, PCDFs) were monitored in areas characterised by different geological environments surrounding three municipal solid waste landfills (Palermo, Siculiana and Ragusa) in Sicily (Italy) in three sampling campaigns. The total concentrations of the 16 PAHs were always below t…
A practical ethylene polymerization for vinyl-polyethylenes: synthesis, characterization and catalytic behavior of α,α’-bisimino-2,3:5,6- bis(pentame…
2016
A series of α,α′-bis(arylimino)-2,3:5,6-bis(pentamethylene)pyridyliron chlorides was synthesized in a one-pot reaction and characterized by FT-IR and elemental analysis as well as X-ray crystallography for one representative iron complex, where the Fe center adopts a distorted square pyramidal geometry with three coordinating nitrogen and two chlorine atoms. The iron precatalysts, upon treatment with either methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), exhibit high activities in the range of 107 g of PE per mol of Fe per h toward ethylene polymerization, yielding highly linear and, more importantly, vinyl-polyethylenes. The correlation between the structural features of iron…
Changes in epizoic crustacean infestations during cetacean die-offs: the mass mortality of Mediterranean striped dolphins Stenella coeruleoalba revis…
2006
In the summer and autumn of 1990, a cetacean morbillivirus caused a massive epizootic mortality of striped dolphins Stenella coeruleoalba in the western Mediterranean. Previous circum- stantial evidence suggested that the disease could also have increased host susceptibility to infesta- tions with epizoic crustaceans. In this study we provide strong evidence supporting this hypothesis. We examined striped dolphins stranded along the Mediterranean central coast of Spain from 1981 to 2004 (n = 136), and recorded data on prevalence, intensity of infestation, size and reproductive status of 2 sessile crustacean species specific to cetaceans, the phoront cirriped Xenobalanus globicipitis and the…
Estimation of the environmental hazard of organochlorines in pulp mill biosludge used as soil fertilizer
1993
Abstract Contents of total organic chlorine and polychlorinated phenols, guaiacols, catechols, benzenes, cymenes, cymenenes, naphthalenes, toxic dibenzodioxins, toxic dibenzofurans, toxic PCB congener 77, alkylated dibenzofurans, alkylated bibenzyls and alkylated phenanthrenes in spent biosludges from activated sludge treatment plants of chlorobleaching kraft pulp mills are reported. Some estimations of hazard caused by these organochlorines to humans and wildlife from the use of biosludge as soil fertilizer are constructed and discussed.
Organic chlorine compounds in lake sediments. III. Chlorohydrocarbons, free and chemically bound chlorophenols
1990
Abstract Chlorohydrocarbons and free and chemically bound chlorophenols, catechols and guaiacols were measured from lake sediments in Central Finland. Chlorohydrocarbons occurred at low backround levels except chlorocymenes from pulp mills and PCBs near the city of Aanekoski, where a local leakage occurrs. Free chlorophenols (hexane extractables) were found in all 18 areas studied, but the bound ones (extracted with strong alkali) only in the pulp mill reciepient lakes where they dominated. Preliminary analyses of chemically bound chlorophenols in high molecular fractions of spent bleach liquors and pulp mill effluents indicated that majority of chlorocatechols and guaiacols are bound alrea…
Bioaccumulation of dioxins, coplanar PCBs, PCDEs, HxCNs, R-PCNs, R-PCPHs and R-PCBBs in fish from a pulp-mill recipient watercourse
1993
Abstract Pike, perch and lake bream from the river Kymijoki were analyzed by gas chromatography/mass spectrometry (GC/MS) for toxic polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), hexachlorinated naphthalenes (HxCNs), non-ortho substituted polychlorinated biphenyls (coplanar PCBs) and alkylchloroaromatics of pulp mill origin. In most fish, the only congener of PCDD/PCDFs found was 2,3,7,8-TeCDF (
Optimization of large-volume injection for the determination of polychlorinated biphenyls in children's fast-food menus by low-resolution mass spectr…
2008
International audience; This study includes the determination of five indicator polychlorinated biphenyls (PCBs) (52, 101, 153, 138, and 180), six non-ortho PCBs (35, 80, 81, 77, 126, and 169), and two mono-ortho PCBs (28 and 118) in fast food for children. A freeze-dried sample of 10 g is extracted by using pressurized n-hexane in two 5 min cycles at 120 degrees C and 100 mbar. Fatty extracts were cleaned up by means of acetonitrile/n-hexane partitioning and gel-permeation chromatography. The fractionation of non-ortho, mono-ortho, and indicator PCBs was made on graphitized carbon solid-phase extraction cartridges by using n-hexane, n-hexane/toluene (99:1, v/v), and toluene as elution solv…
Lipid-containing semipermeable membrane devices (SPMDs) as concentrators of toxic chemicals in the lower Fraser River, Vancouver, British Columbia.
1998
Abstract Semipermeable membrane devices (SPMDs) were deployed in the water column and in the sediments of the Lower Fraser River (B.C., Canada) to compare the levels and the congener profiles of polychlorinated dibenzo- p -dioxins (PCDDs), dibenzofurans (PCDFs) and non- ortho -chlorinated biphenyls (N-o,o′-PCBs) against those sampled by an Infiltrex resin column water sampler. Also the relationship between what was present in the ecosystem as sampled by SPMDs and what was accumulated in the tissue of resident benthic-feeding fish was explored. Only the lipid portion of the SPMDs was prepared for analysis, due to some technical difficulties in cleaning the polyethene tubing. The calculated w…
New qsar models for polyhalogenated aromatics
1994
Electronic properties of polychlorinated dibenzo p dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and polychlorinated diphenyl ethers (PCDEs) were calculated using the semi-empirical AM1 method The calculated electronic descriptors — the energy of the lowest unoccupied molecular orbital (ELUMO), the energy of the highest occupied molecular orbital (EHOMO), the ELUMO-EHOMO gap (dE), and molecular polarizability — are related to the Ah receptor binding affinity values of PCDDs, PCDFs, and PCBs and immunotoxicity values for PCDEs The quantitative structure activity relationships (QSARs) based on chlorine substitution patterns were also constructed, an…
Occupational exposure to chlorinated and petroleum solvents and mycosis fungoides.
2013
OBJECTIVE: To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF).METHODS: A questionnaire on lifetime job history was administered to 100 patients diagnosed with MF and 2846 controls. Odds ratios (ORs) were calculated as the measure of the association between exposure to each specific solvent and MF.RESULTS: In the total sample and in men, cases and controls did not differ in relation to exposure to any of the solvents studied. In women, an association with MF was seen for the highest level of estimated exposure to perchloroethylene (OR = 11.38; 95% confidence interval: 1.04 to 124.85) and for exposure less than …