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Industrial activities cause a variety of environmental problems. These are largely caused by emissions of air pollutants, the production of waste and depletion of natural resources. As a consequence, industrial managers face a complex problem when assessing the overall environmental pressure on the environment, and options to reduce this pressure. This complexity is associated with the range of activities taking place in industrial processes, the variety and complexity of their environmental effects, the number of available technologies for pollution control, and the costs of pollution reduction. Despite this complexity, pollution reduction in industry is not always based on systematic analyses, nor on clearly defined company priorities to environmental management. An important reason for this is a lack of integrated analyses of the environmental impact of industrial processes, the options to reduce this impact and the associated costs. An instrument to assist plant managers in deciding on environmental management is of utmost importance. However, a decision support tool that takes a company perspective and covers all relevant environmental issues as well as costs of environmental management is currently not available in the literature. The overall objective of the thesis is to develop a decision support tool to analyse options to reduce the environmental impact of an industrial company. A model is developed for the assessment of the potential environmental impact resulting from emissions of environmental pollutants, as well as the effectiveness of reduction options and the associated costs. The tool aims to take a company perspective and to assist the company management in the analyses of possible strategies to improve the company's environmental performance. An industrial plant, supplying the automotive industry with aluminium pressure die casting products, located in Portugal, served as case study. The following research questions are addressed: 1) What existing environmental systems analysis methods and tools can in principle be combined in a decision support tool and used to analyse the environmental performance of a plant from a company perspective? 2) Which technical pollution reduction options are available for reducing the environmental impact of an aluminium pressure die casting plant? What are their technical potentials to reduce this impact, and the associated costs for the plant? 3) How can a model be developed that can be used from a company perspective to analyse options to reduce the environmental impact of aluminium pressure die casting? 4) How do different strategies to combine pollution reduction options improve the environmental performance of an aluminium pressure die casting plant, and what are the associated costs for the plant?

Transition metals play an important role in many biological processes. Iron is essential for almost every organism, but its bioavailability is limited due to the low solubility of Fe(III) in aqueous environments. Microbial siderophores help solubilize and sequester iron(III). In solution, siderophores like desferrioxamine B (DFOB) are also avid binders of Ti(IV). Ti(IV) is chemically similar to Fe(III), and the use of usually-inert TiO2 is increasing in products such as sunscreens and paint. The surface of titanium metal in joint replacements and implants is oxidized to form TiO2. Microbial siderophores bind to normally inert TiO2 and this binding can affect the solubility of Ti(IV). Dissolution might render Ti(IV) biologically available, and might interfere with Fe(III) biogeochemical cycling, as well as impact biofouling in marine, medicinal, and industrial applications. This research explores how siderophores interact with Ti(IV) in aqueous solutions and can solubilize Ti(IV) from the surface of solid TiO2. Spectrophotometric techniques and isothermal titration calorimetry were used to determine the speciation of Ti(IV)-DFOB and revealed a stability constant of log ~ 40 for Ti(IV)-DFOB when in competition with EDTA. Complementary computational methods were employed to predict the structure of Ti(IV)-DFOB, because no crystal structure has been determined thus far. Dissolution studies of TiO2 in the presence of DFOB were monitored by UV/Vis and ICP-OES to determine the kinetics of Ti(IV)-DFOB formation, using many different crystalline forms of TiO2 at several pH values. Kinetic data confirmed that dissolution of Ti(IV) with DFOB is a two-step process, with one faster, less extensive step and a slower step involving additional Ti(IV). Introduction of small organic acid-derived ligands such as oxalate, citrate, ascorbate and succinate changed the dissolution kinetics, suggesting a synergistic cooperation between oxalate-DFOB dissolution, while the others revealed inhibitory behavior. Exposure of sunscreen products that contained TiO2 to DFOB was also investigated to determine biological effects on siderophore binding. Further investigative studies were conducted using SEM and TEM to address the surface interactions of TiO2 with DFOB. Understanding these interactions is necessary to determine the effects of binding, the interactions of these complexes in aqueous environments and how they behave chemically in biological systems. Varying concentrations of Fe(III) and Ti(IV) were introduced together with DFOB to determine by using UV/Vis spectroscopy what metal will bind preferentially. ESI-mass spectra were obtained of these solutions to further confirm metal binding. DFOB-mediated mineral dissolution studies were explored by spectrophotometry and ICP-OES to determine the amount of soluble metal released into solution from -hematite Fe2O3, anatase TiO2 and pseudobrookite (Fe2TiO5) and the kinetics of dissolution. Finally, surface analysis was conducted using SEM and TEM to observe the effects of DFOB on the mineral phase. The demonstration that DFOB can bind Ti(IV) and solubilize TiO2 raised the question of whether other siderophores could potentially cause the same effects. Another biologically relevant siderophore is pyoverdine (PVD), found in Pseudomonas bacteria. It has been a strong focus since it was found to have many important roles ranging from virulence, cell to cell signaling, and quorum sensing for biofilm formation. Adhesion of these bacteria is often found on titanium surfaces. Biofilms form on biomedical titanium implants and biologically induced corrosion often occurs on TiO2 coated surfaces, such as on the sides of ships and the interior of pipes. PVD was isolated from bacterial culture and characterized. PVD was then exposed to Ti(IV) solutions and monitored by UV/Vis spectroscopy and fluorescence to characterize Ti-PVD formation and speciation, by using the same techniques as Ti-DFOB. Binding of Ti(IV) to PVD was determined using ITC to have a log ~51. Treatment of TiO2 with PVD yielded different results from those observed with DFOB. In particular, putative adsorption of PVD to the surface was seen rather than dissolution of Ti(IV). Growth of Pseudomonas in the presence of TiO2 showed enhanced growth rates and using Ti(IV) complexes, the effects on biofilm growth were determined. Understanding these interactions is necessary to determine the effects of binding, the interaction of these complexes in aqueous environments and how they behave chemically in biological systems. / Chemistry

Volatile and dislodgeable residues from pesticide-treated turfgrass were determined. Four pesticides (isazofos, MCPP, triadimefon, and trichlorfon) were applied separately at the manufacturer's recommended high rate to an established plot of "Penncross" creeping bentgrass. Trichlorfon was applied with and with out irrigation following the application. DDVP and CG-17193, the metabolites of trichlorfon and isazofos, respectively, were analyzed for as well. For each application, a 10 m radius plot was sprayed. The Theoretical Profile Shape (TPS) method was used to estimate source flux from a 10 m radius plot. For each sampling period, 120 mL of XAD-4 resin was placed into an air pump and ambient air sampled for 4 h at an average rate of 0.8 m$\sp3$ min$\sp{-1}.$ Dislodgeable residues were determined by wiping the treated turfgrass with a dampened piece of cheesecloth. All pesticides resulted in less than 13% of applied compound being lost as volatile residues. Both diphasic and diurnal patterns of volatilization were observed. Irrigating treated plots immediately after application greatly reduced initial volatile and dislodgeable residues. However, there was a significant increase in volatile and dislodgeable residues on Days 2 and 3 compared to those residues on Day 1 after irrigation. Irrigation enhanced the transformation of trichlorfon to DDVP, the more toxic compound. Measured volatile and dislodgeable residues were used to estimate human exposure. The air concentrations were compared to 8-h exposure limits (mg m$\sp{-3}$), rat "no-effect" levels (mg m$\sp{-3}$), and the acute toxic LC$\sb{50}$ values (mg m$\sp{-3}$). Dislodgeable residues (ug m$\sp{-2}$) were incorporated into two dermal exposure models. The estimated dermal exposure (mg 70 kg person$\sp{-1}$) was compared to dermal "no-effect" level values. Overall, golfer exposure to volatile and dislodgeable residues were deemed at safe levels in terms of acute toxicity. However, DDVP as a volatile residue, and isazofos as a dislodgeable residue may be of toxicological importance. The bonding of MCPP with Pb$\sp{+2}$ was characterized with UV absorbtion. No interaction was observed.

This study investigates the removal of natural organic matter (NOM) by alum coagulation, and the effect of ozonation on this process. The objectives of the research were: (1) to determine various properties of NOM that are important for its interaction with alum, and the effect of ozone on these properties, (2) to determine the calcium and aluminum binding capacities of unozonated and ozonated NOM, (3) to determine the sorption capacity of unozonated and ozonated NOM on aluminum hydroxide flocs, and (4) to use the data thus obtained to describe NOM removal by alum coagulation, and the effect of ozonation on this process. For the purpose of this research, NOM from a eutrophic raw water source (Forge Pond, Granby, MA) was isolated and fractionated into eight fractions based on relative hydrophobicity and acidity. The fractions isolated were: fulvic acid (FA), humic acid (HA), weak hydrophobic acids (WHYA), hydrophilic acids (HAA), hydrophobic bases (HYB), hydrophilic bases (HYB), hydrophobic neutrals (HYN), and hydrophilic neutrals (HN). The objectives of the research were met with a series of carefully controlled experiments conducted with raw water and the above fractions. It was postulated that the interactions between charged functional groups on NOM molecules and coagulants was responsible for the removal of NOM by alum coagulation. Two mechanisms for such removal are charge neutralization/precipitation and adsorption of NOM on aluminum hydroxide flocs. The acidic NOM fractions (FA, HA, WHYA and HAA) were negatively charged at all pH values, and hence interacted well with the positively charged aluminum hydroxide particles. Of all the NOM fractions isolated, the humic fractions (FA and HA) exhibited best adsorption on aluminum hydroxide flocs. The basic and neutral fractions (HB, HYB, HN and HYN) had little or no charge, and hence exhibited poorer adsorption than the acidic fractions. Calcium and aluminum complexation studies showed that the negative charge on most acidic fractions were only partially neutralized due to metal complexation. The charge on the basic and neutral fractions, on the other hand, were completely neutralized by metal complexation. Thus it was concluded that the charge neutralization/precipitation mechanism of NOM removal was only important for the basic and neutral fractions. Ozonation increased the charge of all NOM fractions. The adsorption of the acidic fractions on aluminum hydroxide flocs either remained unchanged or decreased upon ozonation. Hydrophilic neutrals (HN) on the other hand showed increased adsorption on aluminum hydroxide flocs on ozonation. It was also shown that in the case of Forge Pond water, increased NOM removal on ozonation may only be obtained if ozone is allowed to react with the non humic components of the NOM exclusively.

Though ample evidence supports the detrimental effects of residual chlorine to many aquatic biota, the on-site response of macroinvertebrates has hitherto been little documented. Accordingly, year-long in-stream collections were undertaken to assess and characterize the response of the macroinvertebrate community inhabiting Lampson Brook, Belchertown, Massachusetts. Artificial substrates (limestone chips) were used in the data gathering and a new methodology, Wrona's, was applied to the data analysis. One control station and four downstream stations extending for 3000 meters along the stream were established. All the macroinvertebrates captured at these stations were counted and identified to their lowest taxonomic group. These data were employed to evaluate several diversity indices as well as qualitative and quantitative community comparison indices. The implications of the respective mathematical formulae applied to biological collections were examined and revisions of certain of the formulae are proposed. The combination of density estimates, species richness, EPT value (a value derived from total identified species of Ephemeroptera, Plecoptera and Tricoptera), and a number of selected indices was chosen to describe the impact of chlorinated/non-chlorinated sewage. A list of macroinvertebrate species has been designated as chlorine sensitive/tolerant with the respective total residual chlorine (TRC) concentration. The results indicate that community comparison indices are more sensitive than diversity indices in measuring pollution effects. Community comparison indices, however, showed considerable variations in assessing the severity of the impact. The macroinvertebrate community structures of all the downstream stations were altered due to changes in environmental conditions with regard to all aspects of community parameters. The suspected causes of such disruption in aquatic macroinvertebrate community may be attributed to either the immediate impact of TRC in the water column at station 2 or the chronic effects of stable chlorinated by-products associated with the sediments at stations 3, 4, and 5. The level of impact with regard to each station is a matter of subjective definition as to which are the most important parameters in describing community structure. Different aspects of change in relation to water quality need to be further tested before imposing any judgement on the extent of impact at each station.

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No description available.