Agnes Montangero

Improving Environmental Sanitation, Health, and Well-Being: A Conceptual Framework for Integral Interventions

We introduce a conceptual framework for improving health and environmental sanitation in urban and peri-urban areas using an approach combining health, ecological, and socioeconomic and cultural assessments. The framework takes into account the three main components: i) health status, ii) physical environment, and iii) socioeconomic and cultural environment. Information on each of these three components can be obtained by using standard disciplinary methods and an innovative combination of these methods. In this way, analyses lead to extended characterization of health, ecological, and social risks while allowing the comprehensive identification of critical control points (CCPs) in relation to biomedical, epidemiological, ecological, and socioeconomic and cultural factors. The proposed concept complements the conventional CCP approach by including an actor perspective that considers vulnerability to risk and patterns of resilience. Interventions deriving from the comprehensive analysis consider biomedical, engineering, and social science perspectives, or a combination of them. By this way, the proposed framework jointly addresses health and environmental sanitation improvements, and recovery and reuse of natural resources. Moreover, interventions encompass not only technical solutions but also behavioral, social, and institutional changes which are derived from the identified resilience patterns. The interventions are assessed with regards to their potential to eliminate or reduce specific risk factors and vulnerability, enhance health status, and assure equity. The framework is conceptualized and validated for the context of urban and peri-urban settings in developing countries focusing on waste, such as excreta, wastewater, and solid waste, their influence on food quality, and their related pathogens, nutrients, and chemical pollutants.

Potentials of vertical-flow constructed wetlands for septage treatment in tropical regions

Publisher Summary This chapter presents an assessment of the potentials of vertical-flow constructed wetlands (CWs) for septage treatment in tropical regions where microbial reactions and plant growth rates are substantially high. CWs are proven to be an effective low-cost treatment system, which utilizes the interactions of emergent plants and microorganisms in the removal of pollutants. Three pilot-scale CW beds consist of 65-cm sand gravel substrata, supported by ventilated drainage system, and planting with narrow-leave cattails are taken. During the first year of operation, the CWs are operated at the solid loading rates (SLR) and the application frequencies of 80–500 kg total solid (TS)/m2.yr and 1–2 times weekly, respectively. The SLR of 250 kg TS/m2.yr is found to result in the optimum treatment performances with respect to the TS, total chemical oxygen demand (TCOD), and total Kjeldahl nitrogen (TKN) removal efficiencies of 80, 96, and 92%, respectively, as well as less adverse effect on plant growth. The operating conditions in the second year are rectified by retaining the percolate in the CW beds for the periods of two and six days prior to discharge, but maintain the SLR of 250 kg TS/m2.yr. This operating condition results in the percolate NO3 concentrations of 20–50 mg/L.