In this work, the recent trends in the application of the sulfate radical-based advanced oxidation processes (SR-AOPs) for the treatment of wastewater polluted with emerging contaminants (ECs) and pathogenic load were systematically studied due to the high oxidizing power ascribed to these technologies. Additionally, because of the economic benefits and the synergies presented in terms of efficiency in ECs degradation and pathogen inactivation, the combination of the referred to AOPs and conventional treatments, including biological processes, was covered. Finally, the barriers and limitations related to the implementation of SR-AOPs were described, highlighting the still scarce full-scale implementation and the high operating-costs associated, especially when solar energy cannot be used in the oxidation systems.

As set out in the Sustainable Development Goals, it is necessary to achieve universal and equitable access to safe drinking water services for all the world’s population. Appropriate water treatment alternatives for rural areas should be prioritised to achieve this goal. In this work, a simplified drinking water treatment system (SDWTS), which has great potential for application in small communities and rural areas, was evaluated on a pilot scale for turbidity and apparent colour removal using synthetic raw water. The SDWTS integrates Upflow Gravel Filter in Layers (UGFL) and Rapid Sand Filter (RSF) with previous coagulation. This evaluation was carried out using a 2${}^3$ factorial experiment, with the factors: type of water, type of coagulant and flow. The factorial design showed that the SDWTS had the highest turbidity removal efficiencies (>98.7%) with type II (20 NTU) water and PACl coagulant, while flow rate had no significant effect on turbidity removal. Under optimal operating conditions (type II water, PACl and 1.0 m${}^3$/d), the SDWTS produces treated water that meets the standards required by Colombian regulations and World Health Organisation recommendations for drinking water, concerning the variables: turbidity, apparent colour, total coliforms, $E.$ $coli$, pH, electrical conductivity and Al. The SDWTS maintained its capacity to produce potable water when evaluated with the increased operating flow (up to 3.0 m${}^3$/d) and raw water turbidity (up to 50 NTU). The SDWTS can be an efficient and innovative alternative for water treatment, and its implementation in small communities can contribute to equitable access to drinking water.

Introduction: Enough scientific evidence is available on the harmful effects of air pollution on the health of human beings, fauna, flora, and ecosystems in general. The mechanical and electronical monitoring networks are the first option for the air quality diagnosis, but they do not allow a direct and precise assessment of the impacts in living organisms that may result from the exposure to air pollutants. Objective: To evaluate the changes in the composition of corticulous lichen communities as a response to various stress factors in areas with different levels of air quality to diagnose the state of pollution or intervention in an area with a more complete option. Methods: Air quality contrasts and changes in richness and coverage of corticulous lichens in response to different stress factors, such as land use and distance to roads, in three different biomonitoring areas, were evaluate using GIS, and the data are presented in an easy-to-understand grey scale coded isoline map. Results: Indicators such as lichen coverage (R= -0.4) and richness (R= -0.7) are inverse correlated with PM2.5 concentrations in each area. A total of 110 lichen species were identified, being Phaeophyscia chloantha (Ach.) Moberg and Physcia poncinsii Hue the most frequent species (present in 38 and 33 % of the 86 sampled phorophytes, respectively). The intra-area relationships of lichen richness exhibit significant relationships with regards to the land use and distance to roads (with correlations coefficients greater than 0.5) and the Simpson index was higher than 0.9, in places with better conditions in terms of air quality and microenvironments, likewise the resistance factors calculated suggest that the most sensitive species can be found in environments with a lesser degree of disturbance. Conclusion: These evaluations represent more criteria elements for the diagnosis of the environmental health in the biomonitoring areas.