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Waste engineering fluids, such as coolants and cutting fluids, are difficult to treat because they have variable physical natures, are particularly toxic and have a very high Chemical Oxygen Demand. The complex and unknown chemical content of the many different products available is also problematic. Current technologies, such as nanofiltration or chemical treatment, are quite effective at reducing the COD of the waste metalworking fluids before disposal. These technologies remove free or emulsified oil and high molecular weight components, but they have their limitations. In addition, the more stringent legislation on waste disposal and effluent discharge induces an economical stress on engineering industries. It can be anticipated that future legislations will introduce eco-toxicology measurements into industrial effluent discharge consents. A modular on-site treatment plant to treat semi-synthetic metalworking fluids was developed in this thesis. The approach was to combine different technologies and to inter-optimise their performances. The technologies used were membrane filtration, bioremediation and chemical treatment. The use of activated carbon was also studied. Membrane filtration included the study of ultrafiltration and nanofiltration. For the bioremediation process, a bio-consortia was developed and tested over 8 months. A final design of the whole process is given. The proposed treatment plant transforms the waste metalworking fluid into two products: very low chemical oxygen demand aqueous phase at 30 mg/l COD and a recovered oil showing a calorific value of 42 kJ/kg which could be a possible commodity. The whole treatment plant is scalled-up for thye treatment of 500 L of waste metalworking fluid per day.

The control of atmospheric pollution in the urban environment has, in recent years, taken on important local, national and international significance. Legislation has been introduced in many countries to improve air quality in urban areas. Monitoring air pollution is an important part of understanding and improving air quality. Current standard methods of measuring air pollution only monitor at a single point in space which can lead to ambiguities when assessing air quality over an extended region, such as a city centre or a road intersection. Optical remote sensing techniques, such as long path Fourier transform absorption spectroscopy, overcome the limitations of point measurements by integrating over long paths and thus measuring the average ambient pollutant concentrations. A commercially available Fourier transform infrared (FTIR) spectrometer, together with custom built external optics has been used to make measurements of air pollution in Oxford city centre. It has been shown that it is possible to measure the concentrations of several pollutants simultaneously and in short measurement times. Issues relating to the performance of the spectrometer have been studied, their effects quantified and solutions proposed. Optimal estimation techniques have been applied to the analysis of the single beam spectra recorded by the FTIR spectrometer. This technique has previously only been applied to radiance and transmission spectra and so extensions were necessary. High resolution laboratory measurements of the absorption cross-sections of benzene and 1,3-butadiene have been made and the potential for detecting them in ambient urban air determined.

The ability of zeolites, particularly clinoptilolite, to immobilise Cs arising as an intermediate level radioactive waste is studied. The zeolites are incorporated into Portland cement blends containing additives such as blast furnace slag, pulverised fuel ash and silica fume, and high alumina cement blends. Desorption of Cs+ from the zeolite by ion-exchange cement pore fluid species, mainly K+, Na+ and Ca is studied and ion-exchange isotherms are presented. The Cs distribution between clinoptilolite and cement pore fluid is studied by X-ray diffractometry (XRD) and by chemical analysis of the pore fluid. Some Cs is released into the pore fluid, mainly by ion-exchange with K. The kinetics and mechanism of the pozzolanic reaction between clinoptilolite and Portland cement is studied at various temperatures, using a selective dissolution method, as well as XRD, thermogravimetric analysis and analytical electron microscopy. A model is developed, whereby long-term predictions of clinoptilolite reactivity can be made. Methods of limiting the pozzolanic reaction to ensure the long-term persistence of clinoptilolite in cement by blending are investigated. Slag cements show lowest reactivity. Leach tests are carried out on cement-clinoptilolite cylinders (45x80mm) using a standard leaching method. These confirm the importance of ion-exchange and chemical reactivity in determining leach rate. Additionally, the effect of factors such as clinoptilolite particle size, Cs -loading level, clinoptilolite-cement ratio, quantity and type of cement additive, curing temperature, curing time, leaching temperature and mercury porosity on leach rate are investigated. An optimal cement-clinoptilolite blend is suggested. A method is described for the measurement of oxidation-reduction potential (Eh) of cement pore fluids extracted under pressure, and of measuring the poising capacity of solid and aqueous phases. OPC is mildly oxidising, whereas slag cements provide a reducing environment due to the presence of S-containing species. The implications of E. and pH in terms of radwaste immobilisation are discussed.

Indoor microenvironments can have a relevant contribution towards the total exposure to pollutants. The biomarkers of exposure and effect were analysed in general population, to evaluate the impact of VOCs, PAHs and tobacco smoke exposure in everyday life. We designed a model for toxicological studies, as proof of concept for future studies. We analysed airborne personal exposure to air pollutants, the urinary and oxidative stress biomarkers of three exposure level groups in a non-smoking population from Birmingham, UK, a subset with high exposures to tobacco smoke, and a subset of schoolchildren in Saudi Arabia, living in high pollution areas. A significant correlation was observed between low concentration urinary cotinine and urinary VOCs. Urinary VOCs were found suitable for exposure assessment of general population, although the correlations with oxidative stress biomarkers were weak. No significant correlation between urinary PAHs and oxidative stress was observed in schoolchildren from Saudi Arabia, although certain areas showed a significant increase in urinary PAHs and oxidative stress biomarker. The cell exposure system was designed and tested so it could be applied in future toxicological studies. The observed ROS generation and DNA damage in the cells after exposure, proved the validity of the model for benzene exposure.

The presence of particulate and gaseous pollutants at elevated concentrations in the atmospheric environment is detrimental to public health. The present study has investigated the impacts of a steelworks complex on the air quality in Port Talbot, South Wales, United Kingdom. Different offline and online air monitoring instruments were deployed to four sites around the perimeter of the steelworks (at one coastal site (Little Warren LW) and 3 inland sites placed along the length of the steelworks (Fire Station FS, Prince Street PS and Dyffryn School DS) in the study area for a four-week campaign (April 16 to May 16, 2012). Prior to Port Talbot campaign, a separate two week sampling (March 30 to April 12, 2012) was conducted at Elms Road Observatory Site (EROS) for a representation of an urban background. Gaseous and meteorological data logged during the period of sampling were also collected from the Automatic Urban and Rural Network (AURN) site at Port Talbot Margam (FS site). Hourly and daily data collected were prepared for receptor modelling using Positive Matrix Factorization (PMF) and with the use of Open Air and Lakes Environmental WRPLOT View software, windrose and polar plots were produced to show the directional emissions of particulate and gaseous pollutants. The online sampling instrument of Aerosol Time of Flight Mass Spectrometer (ATOFMS) as well as PMF solutions for Streaker and Partisol were able to identify different processing units of the steelworks responsible for pollutant emissions. The polar plots for most air pollutants revealed the steel industry as the major contributor to air pollution in the study area.

There is growing public awareness regarding the risk associated with poor indoor air quality (Ward, Underberg et al. 2009) and indoors like in the home and workplace (Bernstein, Alexis et al. 2008). The aim of the study is to measure the magnitude of concentration in indoor environments, and personal levels of some air pollutants such as volatile organic compounds, PM2 s, polycyclic aromatic hydrocarbons, oxy-PAHs and Black carbon. Estimate the mass of BC that might be in the breathing zone and the lung dose. To conduct the personal exposure and home and workplace measurements, 45 healthy, non-smoking adult volunteer subjects were recruited. Concentration of the compounds might vary across volunteer's activities, therefore the importance of having personal exposure data which might be more representative. To accurately assess the human exposure and the human risk associates with the air pollution. New or recently remodeled building were found to have high concentration of VOC, therefore, a decay time should be considered before to move into a new buildings. BC particle size concentrations need to be investigate deeply as few information is available. Moreover not information about BC deposited dose was found.

An aerosol chemical ageing (ACA) system has been developed for artificially processing atmospheric particles. An aerosol flow tube coupled to a scanning mobility particle sizer (SMPS) and an aerosol time-of-flight mass spectrometer (ATOFMS) have been proposed to study the heterogeneous reaction (HR) between two oxidants, ozone (O\(_3\)) and hydroxyl radical (OH), and three different single organic aerosol proxies: oleic acid (OL), maleic acid (MA) and bis(2-ethylhexyl) sebacate (BES). The ACA system operates under conditions equivalent to ambient processing times of 1 and 20 days with respect to ozone and OH ambient levels, respectively. The study provides evidence for the ageing process of organic aerosol. The physical characterisation of aged particles suggests the formation of volatile products resulting in appreciable decrease in particles size and mass. The chemical study, however, shows that the properties of the aged particles are sensitive to the oxidant and organic material identities, the particle size and the oxidation environment. The applicability of the developed ageing technique has been tested on real atmospheric particles, however, it is concluded that extrapolating laboratory procedures to ambient atmosphere may be challenging due to the complexity of the real atmosphere, particularly, the urban atmosphere.

Phytoremediation is an emerging green technology for the restoration of contaminated sites with various organic and inorganic contaminants. However, phytoremediation efficiency is limited by factors such as contaminant concentration, toxicity and bioavailability, plant choice and stress tolerance, and competence of indigenous microorganisms. A number of possible solutions have been proposed to overcome these limitations. The use of tolerant plant candidates, mixed plant communities and bioaugmentation with microbes and/or plant growth promoting bacteria (PGPB) have been proposed to suppress plant growth inhibition/phytotoxicity and enhance contaminant degradation through the rhizosphere effect but there is need for more research to understand their impact. This research assessed the impact of contaminant stress (diesel fuel, PAH; phenanthrene, fluoranthene and benzo[a]pyrene, and heavy metal) on selected plant species and microbial community structure, contribution of abiotic processes and rhizoremediation to PAH dissipation, and the impact of PGPB on plant growth and PAH dissipation. These objectives were achieved through greenhouse experiments with M. sativa, F. arundinacea and L. perenne on diesel fuel- and PAH-spiked soils. Diesel-fuel treatments had a negative impact on plant biomass yields while the single and mixed PAH treatments had stimulatory and inhibitory effects on plant biomass yields relative to the control.