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The combustion of pruning residues of olive trees in field is a common practice in South of Italy. Since fields are usually close to densely populated areas, the biomass burning emission may cause seasonally increasing exposure to air pollutants and may present a potential health risk for the population. The goal of this work was to carry out the chemical characterization of PM originated from open burning of agricultural biomass and to provide tracer species or concentration ratios characteristics of this source. In this work preliminary results about the chemical characterization of PM10 aerosol collected a few meters from the plume of a bonfire and throughout its duration are shown. In particular the data showed that during open burning of olive tree residues, PM10 mean concentrations were about fifty times higher than PM10 collected at background site in no biomass burning event. Moreover the particulate matter composition was especially enriched in K, OC, Pb and PAHs, and in particular in benz[a]anthracene and benzo[a]pyrene; this pollutants in fact show the biggest Enrichment Factor values. The BaPfBghiP ratio registered in biomass burning event (1.88) was three times greater than in no event condition (0.57); and this ratio result better than IP/[IP+BghiP] ratio for discriminating between two emission sources of PARs, such as diesel exhaust and biomass burning. Finally BaA has been demonstrated to be a better marker of biomass combustion source with respect to BaP and the other PAHs. [ABSTRACT FROM AUTHOR]

ABSTRACT Polycyclic aromatic hydrocarbons (PAHs) are known to exert mutagenic and carcinogenic effects. Research on extracted organic matter (EOM) from environmental mixtures has indicated several mechanisms of intracellular damage in living organisms. The toxic effect of environmental pollutants is usually assessed on cell systems or in single species. We used the model organism Caenorhabditis elegans to compare the effect of synthetic PAHs with that of the EOM from environmental mixtures. The biological effect was measured by monitoring the expression level of some crucial genes, sensitive parameters of the organism's response. The results indicate the ability of C. elegans to counteract damage by mounting a stress-response only in the presence of EOM. On the other hand the exposure of C. elegans to a mixture of synthetic PAHs determines the silencing of the transcriptional machinery, thus preventing the synthesis of proteins that are important for both the damage repair mechanism and survival itself. The results strongly indicate that the study of environmental toxicant effects at the molecular level may provide information on their mechanism of action. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A method for the determination of Cu(II), Ni(II), Zn(II), Co(II), Fe(II), and Pd(II) at ppb/subppb levels by ion chromatography was developed, improving a previous work of the same authors. In order to lower the detection limits, the direct injection of a large sample volume (5 mL) and 4-(2-pyridylazo) resorcinol solution at pH 6, with hexadecylpyridinium chloride as the post-column reagent were used. The obtained calibration curves were linear (for each metal R2≥0.99) with good reproducibility; the detection limits for Cu(II), Ni(II), Zn(II), Co(II), Fe(II), and Pd(II) were 1.1, 0.46, 39, 0.18, 4.5, and 1.7 ppb, respectively. [ABSTRACT FROM AUTHOR]

Presents a paper making activity for science students. Course objectives; Schedule of sessions; Explaining paper composition to students; Historical account of eastern and western papermaking; Use of papermaking process described by Vance Studley in `The Art and Craft of Handmade Paper'; Brief introduction to pigments, dyes and PH; Grading criteria.