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This work provides new insights on the impact of TiO2/UV catalyzed chemical transformation of moxifloxacin on ecotoxicity effects towards the green alga Pseudokirchneriella subcapitata. The moxifloxacin median effect concentration (EC-50=0.78 [0.56, 1.09] mg L(-1)), determined in accordance to the OECD 72-h growth inhibition test guideline, was 7 times lower than that of the older and widely used fluoroquinolone ciprofloxacin (EC-50=5.57 [4.86, 6.38] mg L(-1)). Applying heterogeneous photocatalysis as an advanced oxidation technique to degrade moxifloxacin in aqueous solution decreased the average growth inhibition from 72% to 14% after 150 min of treatment. No significant carbon mineralization was observed and liquid chromatography mass spectrometry analysis revealed the formation of 13 degradation products for which a chemical structure could be proposed based on accurate mass determination. Combined chemical and ecotoxicological analysis showed that as long as moxifloxacin is present in the reaction solution, it is the main compound affecting algal growth inhibition. However, also the contribution of the degradation products to the observed ecotoxicity cannot be neglected. Photocatalytically induced modifications of moxifloxacin mainly occur at the diazobicyclo-substituent as ring opening, oxidation into carbonyl groups, and hydroxylation. This results into the formation of more hydrophilic compounds with a decreased biological activity compared with moxifloxacin. The change in lipophilicity, and possibly a modified acid-base speciation, most probably also affect the cell membrane permeation of the degradation products, which might be another factor explaining the observed lower residual ecotoxicity of the photocatalytically treated reaction solutions.

This study was conducted in WondoGenet district, Southern Ethiopia to assess the water quality of rural water supply schemes in relation to the sustainability of their service delivery. 28 functional water points were selected randomly, for their assessments. The assessments included sanitary surveillance of water points and water quality analyses. Water samples were analyzed for pH, temperature, total dissolved solids, turbidity, total hardness, fecal and total coliform bacteria, fluoride, chloride, nitrate, manganese, and iron. The results obtained show that most of the 'user perceived' acceptable drinking water quality parameters were within the World Health Organization (WHO) guidelines for drinking water quality, based on aesthetic and taste considerations. Only one dug-well had marginally higher level of total hardness (that is, 220 mg/l of CaCO3), while four water points had higher turbidity ranging from 8.3 to 64 NTU when compared with the WHO guidelines. In all the sampled water points, the level of iron (