Synthesis, characterization and application of steel waste-based iron oxide nanoparticles for removal of heavy metals from industrial wastewaters.

Water treatment and reuse can avail more clean and safe water for human use. In this study, iron oxide waste powder generated from the steel pickling process was used to develop iron oxide nanoparticles (IONPs) using solution gelation synthesis process. The powder and developed IONPs were characterized by X-ray fluorescence and diffraction (XRF, XRD), scanning electron microscopy, Fourier-transform infrared spectroscopy, and Brunauer-Emmett-Teller (BET) analyses. Adsorption experiments were carried out on synthetic water with lead and chromium metal ions. The adsorption data were analysed with Langmuir and Freundlich models. Adsorption kinetics were also analysed with Pseudo-First-Order and Pseudo-Second-Order models using non-linear regression. The synthesized IONPs were porous with active surface functional groups of hydroxyl bonds, with BET specific surface area of 325.02 m2/g. XRD results confirmed the cubic spinel structure of IONPs with particle sizes of 20-30 nm. The nanoparticles at a dosage of 0.35 g in 10 mL for 50 min effectively removed Pb(II) and Cr(VI) metal ions up to 99.9% from both synthetic water and industrial wastewater. The adsorption capacity (qmax) of IONPs was found to be 417 and 326.80 for Pb(II) and Cr(VI) respectively. Freundlich isotherm model data fitted best for the removal of both metal ions. The regression values for kinetic models confirmed that pseudo-second-order best fit the adsorption of both Pb(II) and Cr(VI) confirming chemisorption processes. This study contributes to elucidating alternative application of pickling waste from the steel rolling mills for the benefit of heavy metal removal in industrial wastewater.

Environmental surveillance detects circulating vaccine-derived poliovirus type 2 that was undetected by acute flaccid paralysis surveillance in 2021 in Uganda.

The success of the global polio eradication initiative is threatened by the genetic instability of the oral polio vaccine, which can result in the emergence of pathogenic vaccine-derived polioviruses following prolonged replication in the guts of individuals with primary immune deficiencies or in communities with low vaccination coverage. Through environmental surveillance, circulating vaccine-derived poliovirus type 2 was detected in Uganda in the absence of detection by acute flaccid paralysis (AFP) surveillance. This underscores the sensitivity of environmental surveillance and emphasizes its usefulness in supplementing AFP surveillance for poliovirus infections in the race towards global polio eradication.

Status of Water Safety Plan Development and Implementation in Uganda.

Uganda was among the first countries in Africa that pioneered Water Safety Plan (WSP) development and implementation, with the first WSP dating back to 2002. The objective of this study was to assess WSP status in Uganda, focusing on the experience of the National Water and Sewerage Corporation (NWSC), in order to understand the factors that influenced it and strategies for scaling-up. This study consisted of a review of documentation for 20 WSPs, 42 interviews, a focus group discussion and four field visits. Results show that the development of the 20 WSPs over the last 15 years was largely incomplete and diverse. Most of the WSPs focused on system assessment and improvement, but failed to include WSP monitoring, verification and management. The monitoring of control measures was implemented in nine of the 20 systems, while verification took place in the form of internal (5/20) and external (2/20) auditing. The main barriers identified to WSP implementation were inadequate training, team composition and deployment, mistaken perception and inability to evaluate WSP effectiveness. Conversely, the main enabling factors were management commitment, public health responsibility, good customer relations, financial availability and reliable laboratories. These findings suggest a need for more institutionalization of WSPs with improved coordination across stakeholder groups.