32 Chromatographic residues: Aggressive, explosive (e.g. peroxides) or toxic substances in chromatographic layers or sorbents must be eliminated using suitable methods (washing out, elution) prior to disposal. The solvents used for elution can in many cases be reutilized. Larger quantities of sorbents (e.g. from columns) should be freed from solvents (filtration, drying) and packed into rip-resistant plastic sachets; container I. TLC carrier materials and columns should be disposed of together with the corresponding waste materials (aluminium, glass, plastic); container K.