Worldwide 748 million people lacked access to improved sources of drinking water in 2014, of this group almost a quarter relies on untreated surface water (WHO & Unicef, 2014). According to the WHO, simple, socially accepted and low-cost household water treatment systems (HWTS), such as the Ceramic Pot Filter (CPF), can provide a solution for reliable drinking water on the short term. Although CPFs are used worldwide and are generally effective with regard to bacteria removal, they can in most cases not be indicated by the WHO as a “protective” HWTS, since the virus removal is insufficient. Another limitation of the CPF is the incapability of removing arsenic. Prolonged ingestion of water with elevated arsenic levels can lead to severe health issues including dermal lesions and various types of cancers (WHO, 2011b). The objective of this study was therefore to provide reliable experimental data to investigate whether it is feasible to extend the capabilities of CPFs with arsenic removal properties and enhanced virus inactivation by the incorporation of nano Zero Valent Iron (nZVI), which is a well-known arsenic adsorbent and has also potential capabilities for virus reduction. As a basis for the research approach, the following sub-objectives were formulated: (i) study the arsenic adsorption capacities nZVI amended CPFs, (ii) determine the microbiological inactivation efficiency by nZVI amended CPFs, (iii) evaluate the leaching of the incorporated nZVI and (iv) provide knowledge on the effect of incorporating nZVI into CPFs before firing. In this study Ceramic Disk Filters (CDFs) manufactured by combining clay soil with water and sawdust, pressing them in a disk shape and, firing them. Additionally, metals (nZVI, Composite Iron Matrix powder or silver nanoparticles (nAg)) were added to the clay mixture before firing, to obtain an iron content of 0.05%, 0.5% or 5% based on the weight of a dry disk. The manufactured CDFs were tested based on the following established requirements: (i) arsenic must be removed to below the provisional WHO guideline of 10 ?g/L, (ii) for bacteria a LRV of 2 or greater is required, (ii) for viruses a LRV of 3 or greater is required, (iv) the leached amount of metals must not exceed the WHO guidelines and (v) CDFs should have a flow rate of 0.08-0.24 L/h, which corresponds to 1-3 L/h for a full-size CPF. The removal of bacteria and viruses was quantified by loading the CDFs with test water with Escherichia coli and MS2 bacteriophages, as indicator organisms for bacteria and viruses, respectively. During this filter experiment also the metal leaching from the CDFs was evaluated, an arsenic breakthrough experiment was performed and the flow rates were measured. Furthermore, batch experiments were conducted with ground CDFs, both fired and unfired, to get more insight on the capabilities of the adsorption and inactivation of MS2 bacteriophages and the removal of arsenic, and to study the consequences of firing nZVI into the CDFs. Moreover, knowledge was obtained on the effect of firing nZVI into ceramic material by means of X-ray diffraction (XRD), 57Fe Mössbauer spectroscopy, optical microscopy and Scanning Electron Microscope – Energy Dispersive X-ray (SEM-EDX). The main findings, with regard to the requirements for a CPF, were: (i) although this study showed that ZVI on itself is an effective arsenic adsorbent an immediate total arsenic breakthrough of 200 ?g/L was observed for the CDFs with 5% nZVI; (ii) all CDFs, except the filter with 0.05% nZVI, were able to remove E. coli sufficiently to meet the requirements for bacteria removal (LRV 0.75-4.28); (iii) MS2 bacteriophages were poorly removed (LRV 0.11-0.24) (iv) there is no health-based guideline of the WHO for iron and the leached silver stayed far below the maximum WHO guideline of 0.1 mg/L; (v) the translated flow rates for CPFs were for all type filters higher than the requirement of 1-3 L/h (3.4 – 15.6 L/h), except for the filter with 0.05% nAg (1.5 L/h). Overall, it can thus be concluded that it is not recommended to incorporate nZVI in CPFs before firing with the purpose to enhance the removal of arsenic and viruses. Although, ZVI on itself is well capable of removing arsenic, especially at nano-scale, it was found that when it is incorporated into clay it looses effectiveness and when the clay is fired even more. In the batch experiments the unfired crushed CDF with 5% nZVI was able to remove approximately 90% of the initial 200 ?g/L As(III) in 30 minutes of contact time, while the fired crushed CDF only removed a few per cent As(III). Part of the faster As(III) removal of the unfired filter was a result of sorption by the clay, but the nZVI contributed considerably. Although, the LRVs for MS2 bacteriophages by fired filter material were higher in the batch experiment (LRV 0.42-1.52) than in the filter experiment – probably due more intensive contact - there was also no enhanced MS2 bacteriophage reduction noticed for the fired CDFs with nZVI compared to the fired blank CDF. There are probably several reactions that caused this loss of performance of ZVI. The results of the filter experiments indicated that there was insufficient surface contact with the nZVI particles; either due to unavailability of nZVI particles on the pore surface or due to too high flow rates. The addition of nZVI particles namely led to a considerable increase of flow rate, probably as a result of successive expansion and shrinking of the nZVI during firing. Furthermore, it is hypothesized that due to the vitrification process, in which the clay bonds together, the nZVI became enclosed in the clay structure. Furthermore, the 57Fe Mössbauer spectra evidenced that during firing all the added nZVI was oxidized into hematite, which probably affects the removal of arsenic. Different ZVI corrosion products have a different ability to adsorb arsenic: ZVI exhibits the greatest arsenic adsorption, secondly magnetite, then hematite and lastly goethite (Mamindy-Pajany et al. (2011)). This study showed that ZVI has potential for the removal of arsenic in HWTS, but with application in a different setting than by firing it in the CPF. Suggestions were made for potential alternatives: (i) CPFs with an iron coating; (ii) CPF with ZVI pre-treatment in the form of an hang-element or an extra bucket on top of the CPF, like the effective SONO filter for arsenic removal (Neumann et al., 2013); (iii) CPF with inside iron mixed ceramic pellets (Shafiquzzam et al.,2013). When designing a new type of CPF it is important to make sure that the iron (oxides) particles can be reached and that the flow rate is not too high, which ensures that the contact time with the iron (oxides) particles is long enough. Furthermore, additional research is needed on the enhancement of virus removal and inactivation. It is recommended to study the combination of nZVI and nAg in more detail and also to look at other combination of metals, such as Ag and copper. In order to better understand the adsorption of viruses onto different media it is advised to perform to determine the actual pHPZC of the used media. Lastly, it is advised that in a later stage of future research experiments should be performed with more challenging water and varying parameters such as the turbidity, the pH, competing ions, the ionic strength, influent arsenic concentration and different types of viruses.