As stated by the Rio Declaration on Environment and Development, "Human beings are the focus of concerns related to sustainable development. Everyone is entitled to a healthy and productive life in harmony with nature. "
The generation of waste and its improper management also results in a broken harmony between humans and the environment. Waste can be a major source of environmental degradation (air pollution, soil pollution, water pollution, alteration of ecosystems, health problems, etc..), which is why it is necessary to close all those landfills that do not meet the necessary conditions to deposit waste products of different socio-economic activities. But no matter how correct final management of waste is, this will never eliminate all potential environmental impacts.
For this reason we need to opt for the recovery of the majority of waste generated by means of reusing and / or recycling. But even more important than this recycling, which results from collection at the source, is the reduction of waste generated. And from the amount generated only a small portion should go to final disposal, whether it be a landfill or a waste incineration plant.
There are important differences between countries, both as to the amount generated per capita and the percentage of waste which is collected selectively (glass, paper, cardboard, cans, organic matter, etc.) and does not go to final disposal.
In recent years there has been a steady increase in the selective collection of waste while there has also been a decrease in the generation of waste per capita. Unfortunately, this decline seems to have more to do with the economic crisis of recent years that to a voluntary reduction by citizens, knowing that otherwise a serious environmental problem is being generated. All waste, to a greater or lesser extent, is harmful to the environment.