Waste
Wastes exist as gas, liquid, or solid. When gas or liquid, they are called emissions (or pollution) instead of waste. A waste is only a waste if considered as such. When saying "waste", most people think of a good with a negative value and without owner. These two points could be changed.
Wastes produced by Nature are integrated in recycling processus. (Dry leaves in a forest are transformed in humus by microorganisms). Out of their natural environment, these wastes may become "real wastes" (dry leaves on the supermarket parking). However, the highest quantity of wastes come from human industrial activity, mining wastes, products transformation wastes, wrapping papers. Any resource transformed in product becomes a waste after a certain time. The volume of wastes is roughly similar to the volume of resources used by humans.
Sustainable use require a system view of environment issues. Let's suppose one feels a craving for an apple, and say he has choice between apples coming from Germany, and some from New-Zealand, by boats. Which apple would require the most energy to be eaten ? Depends of the consumer : if he went by bicycle to the shop, the german apple required less energy. However, if he went buy the apple by car, it might be that the energy requirement of the car from home to the shop be higher than the energy required for the apple to travel from New Zealand to the shop. Not even couting CO2 emissions.
When one consider that every product ends up being a waste, it might be a good idea to analyse matters entering a production cycle, rather than analysing wastes usually diluted, resulting of the process. For example, a consumer buying products containing heavy metals in small quantities will probably not detect these heavy metals in the resulting waste. An analysis of products entering the production system, and a guarantee from the provider might be a wiser approach to prevent the final pollution (example : a farmer receiving sewage sludge to landfill on some of his field for fertilizing; the sewage sludge analysis is more likely to reveal the pollution than the soil itself after a couple of years).