There are presented results of analytical research on fertilising microelements and metals, considered as toxic, contained in wastes bearing fertilising macrocomponents. Metal content in agricultural and food industry waste, municipal sewage and sludge, and in hydrolisates from leather scratches treatment is given as well as the microelement composition of manure and of organomineral fertilizers produces by waste composting. Agricultural disposal of those wastes and based on them fertilizers is discussed and the environmental and agricultural regulations limiting such a use are presented.