Whether it is possible to recover re-usable material from waste depends first and foremost on where and in what form the waste is produced. Taking this as a basic criterion, the following alternatives may be distinguished:

1. Collection and utilization of industrial waste and/or production residues at the point where they are generated, and returning them directly to the production process.

2. Systematic sale/purchase of (organic) waste, e. 9. from markets and hotels, for use in agriculture and large-scale livestock farming, primarily pig-fattening.

3. Sorting out and sale of (small) quantities of classified waste from households, offices, production workshops, usually to middlemen; e. 9. glass, paper, metal, plastics.

4. Picking remaining material (remnants) out of mixed waste from dustbins, vehicles and rubbish tips.

Sorting of the waste at the point where it is generated (households, markets, offices, industry) is vitally important, in the interests not only of those who generate and sell the waste, but also of middlemen, processors and public or private waste disposal organizations.

However, whether this is done, and to what extend, depends on whether the waste is directly usable. Because it is with the directly usable waste, i. e. waste that requires no further processing, that most money can be earned. If, in addition, this can be done without any major health risk, then the amount of waste which remains to be disposed of by the public authorities is very considerably reduced.

However, this systematic sorting at the point of origin has its drawbacks. Only mixed waste remains, and this is difficult to recycle. As a result it is practically worthless, and the waste collectors who live from it go empty handed. They lose their livelihood, so to speak. The problem is a tricky one.

To create a situation which is satisfactory for all concerned in the recycling business, the following points should not be overlooked:

• It is hardly sensible that plastic detergent containers, beverage cans, or batteries - to name just a few products first have to be sent off to the tip as mixed waste; they could be sorted out at home and returned to a dealer or buyer who would pay a small amount for them.

Only by sorting waste systematically at the point of origin and by improving working conditions in sorting, transport and reprocessing will the economic advantages of recycling be increased, and the health hazards simultaneously reduced.

So when we consider recycling, we must also be aware of the health hazards and hygiene problems associated with it in the processing and subsequent re-use of the product; we must be capable of getting the risks to those indirectly involved under control;and we must be able to guarantee dependable quality to the consumer.

D Klaus Kresse,

GTZ Division 414