Estrogenicity profile and estrogenic compounds determined in river sediments by chemical analysis, ELISA and yeast assays

An effects-directed strategy was applied to bed sediments of a polluted tributary in order to isolate and identify the major estrogenic chemicals it discharges into the River Po, the principal Italian watercourse. Sediment extract was concentrated by solid phase extraction and then fractioned into 10 fractions by reversed phase high performance liquid chromatography (RP-HPLC). Estrogenic activity of whole extract and fractions were determined using a recombinant yeast assay containing the human estrogen receptor (YES). The 10 fractions and whole extract were analysed for target compounds, e.g. estrone (E1), 17beta-estradiol (E2), estriol (E3), 4-nonylphenol (NP), 4-tert-octylphenol (t-OP), bisphenol A (BPA), using both liquid chromatography-tandem mass spectrometry (LC-MS/MS) and non-competitive enzyme-linked immunosorbent assays (ELISA). The YES assay determined high estrogenic activity in whole sediment (15.6 ng/g EE2 equivalents), and positive results for fractions nr 1, 2, 6, 7 and 8. E1, E3 and NP were the main estrogenic chemicals, however, other unidentified compounds contributed to sediment estrogenicity, particularly for polar fractions nr 1 and 2. A GC-MS screening performed in scan mode identified other potential contributors such as phthalates (DBP, BBP), and OP isomers. A next sampling campaign extended to other tributaries and receiving stretches of the River Po confirmed E1, E3 and NP as major estrogenic chemicals potentially threatening other sites of the main river. In general, target compound ELISAs have been shown to be suitable tools for a rapid screening of wide areas or large numbers of environmental samples for estrogenic risk. The potential for interferences suggests however to use cautiously the concentration values obtained from some of the immunoassays.     

Assessment of the environmental significance of heavy metal pollution in surficial sediments of the River Po

The magnitude and ecological relevance of metal pollution of the middle Po river deriving from the River Lambro tributary was investigated by applying different (complementary) sediment quality assessment approaches: (1) comparisons of concentrations with regional reference data, and (2) comparisons with consensus-based sediment quality guidelines (SQGs), as well as by investigations of the partitioning patterns of target heavy metals (Cd, Cu, Ni, Pb, Zn). Total metal concentrations in the surficial sediments revealed significant pollution inputs on the whole river stretch investigated, with a distinct peak at the inlet of the River Lambro. Based on the geoaccumulation index of target heavy metals, the middle reach of River Po has to be considered as moderately polluted with Cd (1相似文献   

Assessment of biotechnological strategies for the valorization of metal bearing wastes

The present work deals with the application of biotechnology for the mobilization of metals from different solid wastes: end of life industrial catalysts, heavy metal contaminated marine sediments and fluorescent powders coming from a cathode ray tube glass recycling process. Performed experiments were aimed at assessing the performance of acidophilic chemoautotrophic Fe/S-oxidizing bacteria for such different solid matrices, also focusing on the effect of solid concentration and of different substrata. The achieved results have evidenced that metal solubilization seems to be strongly influenced by the metal speciation and partitioning in the solid matrix. No biological effect was observed for Ni, Zn, As, Cr mobilization from marine sediments (34%, 44%, 15%, 10% yields, respectively) due to metal partitioning. On the other hand, for spent refinery catalysts (Ni, V, Mo extractions of 83%, 90% and 40%, respectively) and fluorescent powders (Zn and Y extraction of 55% and 70%, respectively), the improvement in metal extraction observed in the presence of a microbial activity confirms the key role of Fe/S oxidizing bacteria and ferrous iron. A negative effect of solid concentration was in general observed on bioleaching performances, due to the toxicity of dissolved metals and/or to the solid organic component.     

Modelling of the acid-base properties of natural and synthetic adsorbent materials used for heavy metal removal from aqueous solutions

In this paper a comparison about kinetic behaviour, acid-base properties and copper removal capacities was carried out between two different adsorbent materials used for heavy metal removal from aqueous solutions: an aminodiacetic chelating resin as commercial product (Lewatit TP207) and a lyophilised bacterial biomass of Sphaerotilus natans. The acid-base properties of a S. natans cell suspension were well described by simplified mechanistic models without electrostatic corrections considering two kinds of weakly acidic active sites. In particular the introduction of two-peak distribution function for the proton affinity constants allows a better representation of the experimental data reproducing the site heterogeneity. A priori knowledge about resin functional groups (aminodiacetic groups) is the base for preliminary simulations of titration curve assuming a Donnan gel structure for the resin phase considered as a concentrated aqueous solution of aminodiacetic acid (ADA). Departures from experimental and simulated data can be interpreted by considering the heterogeneity of the functional groups and the effect of ionic concentration in the resin phase. Two-site continuous model describes adequately the experimental data. Moreover the values of apparent protonation constants (as adjustable parameters found by non-linear regression) are very near to the apparent constants evaluated by a Donnan model assuming the intrinsic constants in resin phase equal to the equilibrium constants in aqueous solution of ADA and considering the amphoteric nature of active sites for the evaluation of counter-ion concentration in the resin phase. Copper removal outlined the strong affinity of the active groups of the resin for this ion in solution compared to the S. natans biomass according to the complexation constants between aminodiacetic and mono-carboxylic groups and copper ions.     

印染行业清洁生产技术

论述了目前印染行业水污染的现状及原因，指出调整产业结构、应用新工艺、大力提倡节约用水、清沽生产将是印染行业实现可持续发展的必由之路。     

Elemental Composition of Urban Aerosol Collected in Florence, Italy

An extensive investigation is in progress aiming at the characterisation of the air particulate composition in Florence. For our investigation, we use the external PIXE-PIGE beam facility of the I.N.F.N. Van de Graaff accelerator at the Physics Department of the Florence University. In order to gather information on both the longer- and shorter-time trends of the aerosol elemental composition, we are analysing both long temporal series (about 1 year) of 24-h Millipore filters collected by the health authorities in 3 different sites, and filters collected simultaneously in two of the above sites for about one month, by two streakers with one-hour resolution, providing size fractionation between particle size smaller than 2.5 µm and from 2.5 µm to 10 µm. The streakers sampling period includes two days during which the Municipality of Florence has banned the circulation of non-catalytic cars, due to the increase of NO₂ above the "recommended safety values". We present here the first obtained results for the sampling site located near a heavy traffic road.     

Olive mill solid residues as heavy metal sorbent material: a preliminary study

Biosorption of heavy metals is an innovative and alternative technology to remove these pollutants from aqueous solutions using inactive and dead biomasses such as agricultural and industrial wastes, algae and bacteria. In this study olive mill solid residue was used as heavy metal adsorbent material for its wide availability as agricultural waste and also for its cellulosic matrix, rich of potential metal binding active sites. Preliminary studies concerned with the removal of different heavy metals (Hg, Pb, Cu, Zn and Cd), the effect of pre-treatments by water and n-hexane and the regeneration possibility. Olive mill solid residue resulted able to remove heavy metals from aqueous solutions with an affinity series reflecting the hydrolytic properties of the metallic ions, but also a particular affinity for copper. It can be supposed that biosorption phenomenon occur by a general ion exchange mechanism combined with a specific complexation reaction for copper ions. Water pre-treatment is sufficient to reduce COD release in the effluent according to the law limit, while n-hexane pre-treatment strongly reduces also the adsorption properties of this material. Experimental isotherms obtained under different operating conditions were fitted using a non linear regression method for the estimation of the Langmuir parameters. Moreover a simple Scatchard plot analysis was performed for a preliminary investigation of the active sites, showing the presence of two different site affinities depending on the metal concentration, according to the previous hypothesis of two kinds of uptake mechanisms for copper biosorption. Regeneration tests gave good results in terms of yield of regeneration and also concentration ratios.     

Levels of "toxic" and "essential" metals in samples of bovine milk from various dairy farms in Calabria, Italy

The aim of this research was to evaluate the possible contamination by heavy metals of milk from cows bred on various farms in Calabria. The concentrations of heavy metals were determined in 40 samples of bovine milk from the various dairy farms. Each sample, homogenized and powdered, was mineralized in a microwave oven. Quantitative analyses of Cd, Cr, Cu, Pb and Se were performed using an atomic absorption spectrophotometer with graphite furnace; As was analyzed by hot vapor generation technique and Zn with the flame method. As regards toxic heavy metals, highest values are those of As (g.m. 37.90 microg/kg w.w.) and Pb (g.m. 1.32 microg/kg w.w.), while lowest concentrations are those of Cd (g.m. 0.02 microg/kg w.w). With regard to essential metals, Zn (g.m. 2016 microg/kg w.w) and Se (g.m. 13.24 microg/kg w.w.) showed the highest concentrations, followed by Cr (g.m. 2.03 microg/kg w.w.) and Cu (g.m. 1.98 microg/kg w.w.). Further investigations of the levels of heavy metals (As) in a greater number of milk samples from various zones of Calabria are necessary, both to examine this problem from the clinical epidemiological point of view and to identify the possible causes of milk contamination.