There is good evidence that a significant amount of gastrointestinal illness is transmitted via drinking water and that a substantial and increasing proportion of this is due to entry of pathogenic micro-organisms into the distribution system through leaks in pipes. The micro-organisms responsible for these infections occur at very low frequency in drinking water so are extremely difficult to detect. However, the entry of material into a water distribution system is likely to produce other changes in the organisms present within the system, either because additional organisms can enter the system or the addition of organic matter from the incoming water allows some organisms to grow. We will use molecular tools to characterise the whole microbial flora present in water samples taken from water distribution systems and identify samples that are markedly different from those collected from near to the water treatment plant and are therefore likely to have been influenced by material that has entered into the pipes from the surrounding soil.

The environmental occurrence of pharmaceuticals and personal care products in aquatic systems is recognized as an area of increasing concern (Halling-Sorensen et al. 2004). To date, the main focus for environmental research has been on pharmaceuticals of intermediate polarity (Log Kow >1) and not on highly polar compounds (Log Kow -1 to 1) such as cytotoxic drugs (chemotherapy agents). These chemicals by their very nature are designed to prevent or disrupt cellular proliferation and have fetotoxic, genotoxic and teratogenic properties and are considered to be the most dangerous contaminants present in river systems (Rowney et al., 2009). The occurrence of these chemicals in the environment occurs primarily due to discharge from waste-water treatment works (WWTW). WWTW processes do not eliminate these chemicals resulting in trace quantities released with treated effluents into receiving waters. There are currently no regulatory requirements to monitor these chemicals in the environment or statutory maximum emission levels, although this is likely to change in the near future. Water treatment and supply companies, as well as regulatory agencies such as the Environment Agency, OFWAT and the Drinking Water Insepctorate are aware of these emerging chemical contaminants and are keen to see a robust sampling device coupled to a sensitive, reproducible analytical method to allow for routine measurements. The European Medical Agency (EMEA) (which licences the use of these drugs) has proposed that concentrations of 10 ng/L for an individual drug should serve as a trigger value for an environmental risk assessment and yet predicted environmental concentrations at several water intake sites on the River Thames exceed this value in some cases (Rowney et al 2009). The purpose of this studentship is to research a suitable passive sampling matrix to enable the routine, relatively low-cost monitoring of these chemicals in effluents and river water. These compounds are hydrophilic (i.e. log Kow ~-1 to 1) with high aqueous solubilities and present a significant technological and analytical challenge for developing a passive sampler but is entirely suitable for the NERC/ACTF studentship programme. The student, under the expert supervision of a team of Lancaster University and CEH scientists, will test the suitability of a number of polymeric sorbents for 13 of the most common cytotoxic drugs. The project will start by examining uptake/depuration kinetics to determine aquatic sampling rates and will be conducted under carefully controlled laboratory conditions. This work will be coupled to aquatic degradation/transformation experiments to examine chemical behaviour in a range of simulated water types. An analytical method, based on a high-resolution triple quadrupole LC-MS/MS system operated at CEH-Lancaster, will be utilised and the student will be expected to build on an initial analytical method developed for cyclophosphamide (common anticancer drug). Importantly, Unitied Utilities (UU), a major water supply/treatement company in the NW of England, will serve as a CASE partner providing additional training opportunities for the student (by allowing access to their analytical laboratory in Warrington) and allowing passive samplers to be deployed at their WWTWs. UU will be involved in all stages of the project and is keen to see the analytical method incorporated into their laboratory programme. It is anticipated that preliminary field data, obtained over a high spatial scale by deploying numerous passive samplers, will then be subject to chemical fate modelling and risk analysis. References Halling-Sorensen B, Nielsen SN, Lanzky PF, Ingerslev F, Lutzhoft HCH, Jorgensen SE. 1998. Occurrence, fate and effects of pharmaceutical substances in the environment - A review. Chemosphere 36: 357-394. (~800 citations, Nov 2009!) Rowney NC, Johnson, AC, Williams, RJ 2009. Cytotoxic drugs in drinking water. Env. Toxcol. & Chemistry. 28:2733

Health impacts from pathogens indexed by faecal indicator organisms (FIOs) arise from water contact and food consumption derived from catchments, rivers, estuaries and coastal waters. However, the risks associated with these exposures are often highly episodic and determined by rates of pathogen shedding, tides, weather and seasons, all of which are impacted by changing climate, and particularly when storminess is included. Point sources include sewage effluents, intermittent discharges from combined sewer overflows, agricultural point sources such as manure stores, and diffuse sources. Faecal loads are attenuated during the soil - fresh water (including groundwater and/or river water) - estuarine - coastal pathway. Better predictions of the fate and transport of these pollutants along their pathways from sources to receptors would inform several health, policy and operational issues, including: - Whether to manage health risks by restricting access to receiving waters or by management of potential sources of pollutants; - When to declare coastal waters closed, and when to reopen them, trading off the health risks against the economic and social impacts; - What further sewage/intermittent discharge treatment to deploy, which involves trading off the financial and carbon costs against the infrequent health improvements; - What agricultural management options to impose, trading off the financial and food security impacts against the potential health improvements? - How better to optimise health and risk-management processes based on scientific evidence vis-a-vis public perception. The proposed research seeks to develop a new integrated model to predict the exposure to and the health impact assessment of pathogen risks, as indexed by FIOs, in near-shore coastal waters. The approach will be to build and validate a FIO fate and transport model which incorporates rainfall and catchment sources to coastal receiving waters, to use this model together with enhanced disease burden modelling and quantitative microbial risk assessment procedures to produce a dynamic quantitative health impact assessment. The overall model will then be used to analyse policy options for range of future scenarios, including climate change (in terms of changes in rainfall), and to relate the outcomes to actual and perceived health risks. The outputs of the research will inform identified policy gaps and afford improved decision making to minimise health risk from FIO.

The recycling of sludge to agriculture is regarded as the Best Practical Environmental Option in Europe. However, there are many challenges with the practice with concern about the risk of pathogen transfer to farm produce being a major issue. In recent years, it has been reported that numbers of Escherichia coli (E. coli) increase significantly following centrifugation. This is known as the E. coli regrowth phenomenon and it is of serious concern because E. coli is used as an indicator of the microbiological quality of sludge-derived products and compliance failure of the quality standards would result in higher disposal costs and loss of consumer confidence in the industry. It has been proposed that the apparent sudden increase in E. coli numbers in sludge subject to centrifugal dewatering is caused by reactivation of viable but nonculturable cells. Subsequent rapid growth of E. coli in the first few days of cake storage following dewatering is likely to be caused by the combination of a ready supply of nutrients and a lack of microbial competition for those nutrients. The hypothesis to be tested in this research is that the regrowth of E coli in stored sludge can be reduced by the application of the competitive exclusion principle; i.e. by competition between E. coli and fast-growing non-pathogenic bacteria that will be introduced to the dewatered sludge. The principle of competitive exclusion has been used successfully as a means of infection control for many years in the food industry. In this research we aim to develop inocula of differing microbial community composition and evaluate their ability to suppress the growth of E. coli in digested sludge. Objective 1: Test the competitive exclusion concept To test the basic premise of the research, a controlled and replicated bench-scale experiment will be designed in which sludge samples are sterilised and then re-inoculated with E. coli and competing microorganisms. In this experiment the E. coli will be challenged with inocula which present differing degrees of competition for available resources. Where the E. coli are presented with no or limited competition we would expect an increase in population. Where E.coli have to compete with a diverse and well adapted community for available resources we would expect population growth to be slower or absent. Objective 2: Optimise the competitive exclusion product Once the competitive exclusion concept has been successfully tested a competitive exclusion product will be optimised. We will investigate: (i) What is the best source of the challenge inoculum - for example from soils or from digested cake itself. (ii) How big does the competing population need to be? Is a seed population sufficient to compete with E. coli? Or is it necessary for the competitive exclusion product to reach a certain size before it is capable of competing? (iii) How important are key characteristics of microbial community structure of the competitive exclusion product. Measurements of the structure of the microbial community will be made by means of phospholipid fatty acid (PLFA) phenotypic profiling. Objective 3: Scale-up Once proven on bench scale, the culture work will be scaled up using a pilot-scale fermenter. Should the results of this pilot-scale work be promising there will be the opportunity to trial the process at full scale at a United Utilities facility.

The devastating moorland wildfires of June and July 2018 which ravaged large parts of Northern England were the worst peatland wildfires since 1976. Severe wildfires, as distinct from managed burning, can act as a catalyst, resulting in catastrophic change in surface vegetation, soil and water runoff systems. Removal of vegetation by fire, coupled with changes to soil physical and chemical properties, enhances runoff and increases delivery of sediment and other contaminants to drainage systems. Although fire is a significant driver of change in moorland habitats the downstream impacts remain largely unknown. Given that such wildfires are likely to increase in frequency as the climate changes, the recent 2018 fires provide a rare opportunity to capture new data on the impact and response of these burnt moorland catchments in the immediate aftermath of the event. In this project we will quantify sediment and contaminant delivery to upland reservoirs from burnt catchments. We will work with local landowners and responsible authorities to promote recovery of these sensitive catchments by actively facilitating knowledge exchange between researchers and land managers. The overall objective of the project is to quantify sediment and contaminant delivery from upland catchments in the immediate aftermath of a severe wildfire which affected Northern England in July 2018. The general approach considers the fate of fire-generated 'sediment' from source-to-sink along the upland sediment cascade from eroding moorland hillslopes, through the upland channel network to deposition in downstream reservoirs. We will characterise sediment sources within the catchment so that sediment fingerprinting can be used to trace burnt sediment as it moves downstream. Mapping of the catchment will allow us to determine the pathways eroded sediment takes from the hillslopes, through the stream channels and into the reservoirs. Using a combined approach of trapping sediment in the reservoir and the stream network we will quantify the fluxes of eroded sediment (e.g. total, contaminant, organic, inorganic) from the catchment downstream. By analysing sediment cores for charcoal layers deposited in the Victorian reservoirs we will reconstruct a history of fire events in the local region. This information will be extremely valuable in addressing several fundamental questions including whether catchment erosion rates significantly increased after severe moorland fires and which areas are particularly at risk?; and how significant are the current fires in comparison to the historical record of fires in the area?. By establishing clear pathways of knowledge exchange between researchers, local landowners and restoration teams we will directly assist in the recovery of the catchments from the impacts of the fire.