Nanoclays as Eco-friendly Adsorbents of Arsenic for Water Purification

The presence of arsenic (As) in water intended for human consumption and wastewater represents a high level of dangerousness for both human health and the environment. Partial or complete removal of this metalloid from water is an important objective for environmental remediation in many parts of the world. Generally, As is present as As(III) and As(V) in water; the As(III) species is more harmful to humans. The use of original and modified nanoclays is a promising new technology for elimination of all traces of As by adsorption. Nanoclays display important characteristics that make them a viable methodological alternative for adsorption of polluting metals. They are abundant in nature and inexpensive, have high biocompatibility, and can be reused. Strategic functionalization of nanoclays allows optimization of the process of absorption of some polluting metals because modifications of the original clays allow control of their composition and change several parameters – such as the surface area, interlaminar space and volume, and porosity – that are responsible for the adsorption and desorption properties of the clays. This aim of this chapter is to review current developments in the use of original and functionalized nanoclays for removal of As by adsorption processes. The outlook and future prospects for this methodology are also discussed.Fil: Baigorria, Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Cano, Leonardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Alvarez, Vera Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentin

Best practices for an insecticide-treated bed net distribution programme in sub-Saharan eastern Africa

<p>Abstract</p> <p>Insecticide-treated bed nets are the preeminent malaria control means; though there is no consensus as to a best practice for large-scale insecticide-treated bed net distribution. In order to determine the paramount distribution method, this review assessed literature on recent insecticide treated bed net distribution programmes throughout sub-Saharan Eastern Africa. Inclusion criteria were that the study had taken place in sub-Saharan Eastern Africa, targeted malaria prevention and control, and occurred between 1996 and 2007. Forty-two studies were identified and reviewed. The results indicate that distribution frameworks varied greatly; and consequently so did outcomes of insecticide-treated bed net use. Studies revealed consistent inequities between urban and rural populations; which were most effectively alleviated through a free insecticide-treated bed net delivery and distribution framework. However, cost sharing through subsidies was shown to increase programme sustainability, which may lead to more long-term coverage. Thus, distribution should employ a catch up/keep up programme strategy. The catch-up programme rapidly scales up coverage, while the keep-up programme maintains coverage levels. Future directions for malaria should include progress toward distribution of long-lasting insecticide-treated nets.</p