HEPA filter is normally recommended for removal of Mycobacterium tuberculosis from the airstream. Due to its high cost, a cheaper air-filter substitution is proposed in this study. Both low-and high-grade glass fiber air filters were coated with 5% TiO 2 using either polyethylene glycol (PEG), Silane (Si-69), or DURAMAX (D-3005) as a binder. The coated filter was placed in a test duct and irradiated with UVA at an intensity of 4.85 ± 0.41 mW/cm 2 to investigate photocatalysis for M. tuberculosis. The effects of dark and light conditions as well as initial exposure to UVA on bacterial removal were studied. Silver-doped and iron-doped TiO 2 at different concentrations were also tested using face velocities of 0.1 and 1 m/s and humidity levels of 50 ± 10% and 70 ± 10% RH.The most appropriate binder for coating TiO 2 onto filters was 3% D3005. Using 0.1% metal-doping, 100% removal efficiencies were found. Dark/light conditions affected the hydrophobic/hydrophilic properties of TiO 2 -coated filters and the removal efficiencies. The removal rate could be increased by extending the warm up period of the lamps. When the face velocity was increased, the removal efficiency dropped in both filters. Similarly, high humidity adversely affected the removal efficiency, particularly with the coated high-grade air filter.

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Of recent concern is the degradation of plastics from macro- to micro- and even nanosized. This study investigates the content of microplastics and nanoplastics (MNPs) particles in raw water sources for the local population and in tap and drinking water as treated water. A total of 189 samples were selected and analysed for the quality and quantity of MNPs. The results found MNPs in all water samples, with an average abundance ranging from 204 ± 54 to 336 ± 87 particles/L in raw water, from 22 ± 7 to 33 ± 12 particles/L in tap water, and from 25 ± 15 to 73 ± 30 particles/L in drinking water. MNPs were divided into three categories according to their shape. Fragments and fibres clearly dominated in all samples. The majority of particles with sizes greater than 125 μm are found in raw water, while those with ranging sizes from 20 nm to 125 μm are mostly found in treated water. The MNPs were domains of fibres and fragments. The majority of the MNPs were composed of polyethylene terephthalate, polypropylene, and polyethylene (PE). This study contributes to filling the knowledge gap in the field of emerging MNPs pollution of raw and treated water, which is of concern due to the potential human exposure to MNPs.