Management of phosphorus in water: case study of the Tietê River, Brazil
Abstract Strategies for managing phosphorus in the environment have been considered to be of great significance. In light of debates about protecting water resources, tools for recovering and recycling phosphorus are being assessed, with the aim of guaranteeing the sustainability of natural reserves. This study discusses phosphorus dynamics in the environment and measures geared towards the management of its presence in water. In order to illustrate the situation in Brazil, we present an assessment of the size of the potential phosphorus load that is discharged daily into the Tietê River, State of São Paulo, by the urban population living in its basin. Due to its replacement in powdered detergents, the results showed a potential reduction in the amount of phosphorus discharged into the Tietê of about 11.7 t day-1. The size of the potential phosphorus load that might be recovered from sewage sludge shows a scenario of great potential for re-using and recycling in agricultural areas, as long as the necessary care is taken regarding safety and environmental protection. Management methodologies, such as Cleaner Production (CP) techniques, are important tools for controlling water pollution, as they contribute to the reduction of phosphorus emissions. They can therefore improve the perception producers and consumers have of this issue, introducing reducing, recycling and recovering concepts, and assisting in compliance with public policies geared towards preserving the environment.