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The release of fluoride from the production of aluminium, and the subsequent impacts of deposition in the environment, is well documented (Weinstein and Davison, 2004). However, changes are occurring within the industry, driven by technological advances and growth in global manufacture, which have the potential to alter the impact of the aluminium industry on the environment. There needs to be a better understanding of the toxicity of Sodium hexafluoroaluminate (cryolite, Na3AlF6), the impact of modern operating procedures on the release of particulates in to the environment, and finally, an investigation of the longevity of fluoride concentrations in vegetation from industrial pollution once emissions cease (EU, 2008). The toxicity of cryolite exposure to 1st and 3rd instar Diamondback moth larvae (Plutella xylostella (L), Lepidoptera: Plutellidae) was studied through a series of bioassays. There were inter-stage variations in both the lethal and sub-lethal responses to cryolite, whereby low mortality corresponded with high sub-lethal effects and vice versa. A dose-related response threshold was observed in both instars indicating that the physical nature of cryolite plays a role in the toxic mode of action. The comparative toxicity of cryolite from the pot-rooms of Lynemouth smelter and pesticide Kryocide© (Cerexagri, Inc) was investigated along with the role of particle size and the purity of the cryolite particulate in the mode of action. Although both physical and chemical factors played a role in toxicity, these factors formed a hierarchy and the mode of action had a significantly over-riding chemical grounding. Dust samples were collected from the vicinity of Lynemouth smelter for a period of 10 months in order to quantify the impact of modern aluminium production on the environment. Although the volumes of dust collected at any one site were lower than the European Community Short Term Ambient Guideline Concentration of Particulate Matter, dust deposition corresponded with aluminium production rates at the smelter showing that, despite Better Available Technology at the smelter, modern aluminium production still impacts on the environment. When Anglesey Aluminium Metals Ltd ended its operations in September 2009, it created a unique opportunity to assess the long-term impacts of fluoride pollution on the environment. Samples of soil, leaves and lichens were collected to monitor the changes in fluoride content over a 15 month period. The results showed that fluoride contamination of vegetation from industrial processes had a short-term impact once emissions ceased and that mineral-based soils had limited potential as contaminating sources for plant uptake. The mode of action of cryolite toxicity and the impact of waste disposal and fugitive release of cryolite in to the environment are discussed.

Pharmaceutical residues, a group of emerging micro-pollutants, have been globally detected in the aquatic environment since 1990s. As such micro-pollutants are likely to harm human beings and the eco-system, to remove pharmaceuticals from the environment is of great concern. Potassium ferrate (VI) is able to remove a wide range of organic and inorganic pollutants from wastewater. However, the knowledge of treating pharmaceuticals by ferrate (VI) is limited. Therefore, this study aimed to assess the ferrate (VI) performance in the removal of selected pharmaceuticals from water and wastewater and with the following objectives: I) to investigate the removal of selected pharmaceuticals from test solutions and wastewater by ferrate (VI); 2) to assess the influence of solution pH and ferrate (VI) dose towards the treatment; 3) to determine rate constants of ferrate (VI) with selected pharmaceuticals; and 4) to identify oxidation products (OPs) of selected pharmaceuticals during ferrate (VI) treatment. Results revealed that, in test solutions, ferrate (VI) could remove ciprofloxacin (CIP), sulfamethoxazole (SMX), diclofenac (DCF) and carbamazepine (CBl) with a high efficiency (>80%) in optimum conditions, and ferrate (VI) demonstrated considerable apparent second-order rate constants with these four compounds at pH 8 and 9. Moreover, possible OPs of CIP, SMX, DCF and CBl during ferrate (VI) oxidation were identified and their degradation pathways were tentatively proposed. On the other hand, the removal efficiencies of ibuprofen (IBU) and bezafibrate (BlF) by ferrate (VI) were less than 45%, and their rate constants were below 0.5 M-I s - I at pH 8 and 9. No OPs of IBU and BlF were detected during ferrate (VI) oxidation. In the secondary effluent samples from Shieldhall wastewater treatment plant (WWTP) in Glasgow, 15 pharmaceuticals were targeted and eight of them, with concentrations up to 1080 ng/L, were detected. Reduction of naproxen (NPX), lidocaine (LDC) and CBZ in the raw effluent samples was achieved above 40% with 4 mgIL ferrate (VI) at pH 4-8. In the modified effluent samples spiked with 15 target compounds at 10 ug/L, low reduction rates of target compounds were observed (<50%), except for CIP, SMX and erythromycin (ETM). In both test solutions and effluent samples, raising ferrate (VI) dose improved the treatment performance, while the influence of solution pH varied among different pharmaceuticals. For the first time, this study investigated the treatment of BZF by ferrate (VI) and the possible OPs of CIP and DCF during ferrate (VI) oxidation. From this study, it has been demonstrated that ferrate (VI) can efficiently remove pharmaceuticals containing electron-rich moieties (ERMs) and thus is promising in the decontamination of pharmaceutical residues in water and wastewater.

The objectives of this research were to investigate the effectiveness of iodine as a means of chemical disinfection. and storage treatment on the removal of E.coli as indicator organisms in polluted water and to investigate the application of these techniques to the provision of potable quality water in disaster situations. To demonstrate the viability. or otherwise of iodine as a means of chemical disinfection. various concentrations of iodine (0.5 to 10.0 mg/l) were employed to inactivate E.coli as an indicator organism in low quality waters prepared by adding kaolin. stream sediments. digested sludge. raw sludge and an artificial suspension of hydrazine sulphate and hexamethylenetetramine as the sources of turbidity and total organic carbon (TOe). Five turbidity and TOe ranges. three temperature levels and three pH values were also employed during the investigation of iodine disinfection. The results obtained were compared with those of an arbitrarily selected standard of 1.0 mg/l chlorine. This investigation has demonstrated that under all the conditions for which dosages of 8.0 mg/l iodine were employed. a water of virtually potable quality was obtained within a 30 minutes contact period. except those containing raw sludge of more than 7 NTU. Under none of the highest inveStigated conditions (350 C. 9.0pH and 93-100NTU) of natural water samples was a dosage of 1.0 mg/l iodine found to be an effective disinfectant. Both 1.0 mg/l chlOrine and 2.0 mg/l iodine were generally effective in the samples having lower TOe values Le. kaolin and stream sediments at all investigated turbidity. temperature and pH conditions. The above dosages were also found effective in the samples containing digested sludge at the lowest investigated ranges of turbidity. temperature and pH (5- 7NTU. 50e and 6.0pH). The diSinfecting capabilities of iodine in almost all the samples were found to decrease with an increase in turbidity. TOe. temperature and pH. An investigation was carried out to demonstrate the effectiveness of storage treatment by employing low quality water containing 5 and 100 NTU of stream sediments and raw sludge at 50. 200 and 350e and at 6. 7.5 and 9 pH revealed that the efficiency of this process v increased with the time of storage. Its effectiveness was also found to depend upon pH and temperature. Two days storage brought considerable improvement in the quality of water treated at 350C. Seven days storage inactivated more than 90% E.coli in most of the samples treated at 200 and 350C. However. for all types of water employed under all conditions of turbidity. pH and temperature. a storage of 14 days was needed to remove all E.coli. A strategy for the treatment of poor quality water in disaster situations based upon the results achieved from above investigations was prepared. An algOrithm of the decisions for urgent provision of water in disaster situations was also produced. Overall. the results obtained from these investigations indicate the potential of water treatment by storage and by using iodine as a means of chemical disinfection in disaster Situations in which only poor quality water containing a high proportion of organic matter over a range of pH and temperature values is available.

Persistent organic pollutants (POPs) are defined by their characteristic properties in the environment, such as adverse effects on humans and other organisms, a low degradation rate, a potential for bioaccumulation and long range-transport. These properties are the reason that POPs are monitored in remote regions, like the Polar Regions and open oceans, even though they were mostly used in populated areas (urban or rural). A group of POPs was banned under the Stockholm Convention on Persistent Organic Pollutants in 2001 by a number of countries and more chemicals have been added to the list subsequently. To assess the effect of international regulation more information about the long-term fate of these chemicals, the transport processes and the exchange between different environmental media is needed. The first part of this thesis describes long-term trends of POPs such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in the environmental compartment air. One study discusses the trends that were observed with passive air samplers in remote locations along a transect across the UK and Norway. The air• concentrations monitored from 1994 to 2008 at 11 sites showed a general decline. While the total air concentrations decreased with increasing latitude, the decline rates did not differ between sampling sites. A second study discusses the trends of PCBs in the UK atmosphere for urban and rural sites. As in the remote areas, a steady decline was observed following first order kinetics. The PCB concentrations at each sampling site were directly proportional to the population density of the area. It was therefore concluded that air concentrations of PCBs are currently still defined by the direct input from primary source emissions and the observed decline mirrors a decline in emission. In order to assess the fate of POPs in other environmental media soil cores were collected following the transect for the passive air data across the UK and Norway. The soil cores were collected at identical locations ten years earlier. A direct comparison of the data between the sampling years proved that the decline in soil is more variable than in air for most monitored POPs. While there were nearly no changes in soil concentrations of organochlorine pesticides, there was a slight decline for PCBs and a strong decline for PBDEs. Changes in the burden, of PCBs per unit soil organic matter between 1998 and 2008 indicate the approach of soil-air equilibrium for the monitored sites. However chiral data and atmospheric data from the regions indicate that the influence of re-volatilization contributed only a minor component of the air burden of PCBs in remote areas of northern Europe. Important tools in monitoring regional and temporal trends of POPs are passive air samplers, which can be deployed at low cost in remote areas. A new type of sampling medium. the sorbent-impregnated polyurethane foam (SIP) disk, was assessed for its applicability for long-term monitoring of PCBs, PBDEs and hexachlorobenzene. Long-term deployment is a necessity for areas with low concentrations. In order to estimate the most precise atmospheric concentrations from the chemicals sequestered on the sampling medium, it would be preferable if the sampler and atmosphere are not in equilibrium and the sampled air volume is therefore directly proportional to the deployment time. It was found that the SIP disk presents a valid alternative to other established passive air sampling media. The last part of the thesis discusses a group of emerging POPs, the perfluorinated compounds (PFCs). PFCs were monitored in a passive air sampling campaign in different Asian countries. Differences were observed in the PFC composition at different sampling sites. These were explained with different usage pattern and regulations in the different countries. Further research is required to gain deeper understanding the transfer mechanism between different environmental compartments for POPs. The application of a model is needed to assess the increasing influence of secondary sources, i.e. revolatilisation from soils on atmospheric concentrations. While long-term studies for emerging compounds already exist, it is necessary to establish similar monitoring campaigns for emerging chemicals.

This thesis attempts to logically follow the full lifecycle of a 'new' persistent organic pollutant (POP), perfluorooctane sulfonate (PFOS). A new estimate of the global historical production for perfluorooctane sulfonyl fluoride (POSF) was produced, before focusing on deriving the first estimate of the global historical environmental releases of PFOS. The total historical worldwide production of POSF was estimated to be 96,000 tonnes between 1970- 2002, with an estimated global release of 45,250 t to air and water between 1970-2012. Estimates indicated POSF-derived products are the major direct source of PFOS emissions, resulting in an estimated release of 450-2700 t into wastew31er streams over the same period. Due to the physiochemical properties of PFOS (soluble in water, negligible vapour pressure, and limited sorption to particles), emissions from consumer products including stain repellent treated fabrics, waterproof apparel, and aqueous fire fighting foams were expected to be largely to waste water. The following papers saw two existing multi-media environmental fate models reparameterised to explore the role of emissions from diffuse consumer use. PFOS emissions were linked to waste water treatment plants, partitioning and emissions uncertainty were explored, and annual fluxes of PFOS were estimated from European rivers at a local and continental scale. A good agreement, generally within a factor of three between modelled emissions derived from population density and measured freshwater PFOS concentrations, was observed. The final paper is a slight departure from the others submitted in this thesis. This paper returns to 'classical' POPs, but looks forward in time to try and understand the potential impact of climate change on POP chemicals. Overall. predicted changes were small even under the most conservative scenarios, resulting in slightly increased volatilisation and degradation in air from a drier and warmer south-western Europe, corresponding to a transfer and redeposition of POPs to the cooler and wetter north-eastern Europe.

This thesis is concerned with an investigation of the thermodynamic parameters of complexation of calix[4]pyrrole derivatives with anions and metal cations, as well as the use of calix[4]pyrrole oligomers and silica based materials aiming at the removal of polluting ions from aqueous solutions.