are given. They are given for most common parameters to characterize wastewater production. The data originate mainly, though not exclusively, from OECD-countries. Data from developing countries on waste production and its environmental impact are difficult to find. Those data that have been reported can often not be interpreted adequately owing to major shortcomings in the description of the relevant processes or the data collection methods. In some cases wa ste parameters have been recorded without indications of relationships with other parameters. Examples of these are:
data on suspended solids without any reference to solid waste;
solid waste data of 5.5 kg manure per ton carcass weight, obviously referring to minor components of the manure, probably the scrapings, but with no reference to other solid waste production (eg rumen content). of the reported values ​​originate from EPA-studies published in the period 1970-1975. Even studies published at the end of the eighties refer mainly to these studies. Moreover, huge variations in waste production per unit of product processed have been found. This variation can be partly explained by looking at the types of products made or processes used, but some variation remains unexplained. But even worse, also in OECD-countries exceptions have been recorded which exceed emission values ​​by manifold, without mention of a possible clue of explanation [1]. Conclusion that needs to be drawn is clear. There is an urgent demand for proper, well described, reference values ​​on waste production. Monitoring programmes need to be set up to allow for a more reliable environmental impact assessment of animal product processing than is presently the case. These monitoring programmes should result in emission factors per unit of product processed. Because of the diversity in processes and waste production, proper data collection on waste processing will be an expensive and time consuming undertaking [15]. Obtained reference values ​​on waste production will always need to be translated to locally relevant processing methods and production situations. Thus, monitoring programs must be arranged so as to make it possible to give a correct interpretation of the reference values.this end monitoring programmes should:
cover all important pollutant parameters (particularly solid waste, water consumption, SS, BOD, N, P, heavy metals and energy consumption);
give a clear description of the production processes to which the data relate, including the quantity and type of product processed; addition steps must be made that measurements are taken prior to wastewater treatment and before the water is diluted with other (waste-) water. If a wastewater treatment plant is available, the reactor performance should be determined for the evaluation of the effectiveness of the water treatment. In su...
