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There are growing concerns about the increasing trends of emerging micropollutants in the environment due to their potential negative impacts on natural ecosystems and humans. This has attracted attention from both governmental and non-governmental organisations worldwide. Pharmaceuticals, personal care products, and endocrine disruptors are continuously being released consciously or unconsciously into water sources due to poor regulatory frameworks especially in the developing countries. The effects of these contaminants are poorly known. They are not easily biodegradable and have become an environmental nuisance and public health issue. This has heightened the risk of exposure to their deleterious effects in such countries where the majority of the population are still struggling to have access to good quality drinking water supplies and better sanitation. With the rising fear of short-and long-term impacts of the ever-increasing number of persistent recalcitrant organic compounds accumulating in the environment, their removal is gradually becoming an issue to the water treatment industry. Hence, there is a need to develop functional techniques for the management of water contaminated by these emerging contaminants so as to increase the availability and access to safe and good-quality drinking water. We conducted a narrative review on these emerging micropollutants and examined their various documented sources, effects, as well as recent techniques for their effective removal. This becomes necessary due to the increasing occurrence of these pollutants in the aquatic and terrestrial environment. These levels are expected to further increase in the coming years as a consequence of the ever-increasing population density which undoubtedly characterizes developing economies. Our findings show that the present reported treatment techniques in the literature such as biological oxidation/biodegradation, coagulation/flocculation, ozonation, el ectrodialysis, reverse osmosis, sedimentation, filtration, and activated carbon were not designed for removal of these newly identified contaminants, and as such, the techniques are not sufficient and unable to completely degrade the compounds. We therefore recommended the need for concerted efforts to develop better techniques, especially combined advanced oxidative methods to address the shortcomings of and growing challenge to current practices. 1 Introduction The importance of good-quality, potable water to human existence cannot be underestimated, and life will be practically impossible or difficult without the availability of safe drinking water (Swaminathan et al. 2013; Cortés Muñoz et al. 2013). Over the last few decades, there have been tremendous improvements in the supply of safe drinking water to growing populations. This is through various governmental interventions especially in developing countries that want to meet the Millennium Development Goal target of 2015 adopted by United Nations in 2000. This mandate is in line with European Commission Water Framework Direc...

Water pollution through natural and anthropogenic activities has become a global problem causing short-and long-term impact on human and ecosystems. Substantial quantity of individual or mixtures of organic pollutants enter the surface water via point and nonpoint sources and thus affect the quality of freshwater. These pollutants are known to be toxic and difficult to remove by mere biological treatment. To date, most researches on the removal of organic pollutants from wastewater were based on the exploitation of individual treatment process. This single-treatment technology has inherent challenges and shortcomings with respect to efficiency and economics. Thus, application of two advanced treatment technologies characterized with high efficiency with respect to removal of primary and disinfection byproducts in wastewater is desirable. This review article focuses on the application of integrated technologies such as electrohydraulic discharge with heterogeneous photocatalysts or sonophotocatalysis to remove target pollutants. The information gathered from more than 100 published articles, mostly laboratories studies, shows that process integration effectively remove and degrade recalcitrant toxic contaminants in wastewater better than singletechnology processing. This review recommends an improvement on this technology (integrated electrohydraulic discharge with heterogeneous photocatalysts) viz-a-vis cost reduction in order to make it accessible and available in the rural and semi-urban settlement. Further recommendation includes development of an economic model to establish the cost implications of the combined technology. Proper monitoring, enforcement of the existing environmental regulations, and upgrading of current wastewater treatment plants with additional treatment steps such as photocatalysis and ozonation will greatly assist in the removal of environmental toxicants.

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