Guidelines for the preparation and verification of neat organic environmental reference materials / Michael A. Re -- The preparation and validation of isotope dilution standards : a case study in PCBs / Daniel L. Bolt and Joel C. Bradley -- Preparation and verification of ICP and AA reference standards / Jean-Pierre Zajac -- The preparation and stability of PCDD/PCDF soil standards / Michael A. Re, Lawrence H. Keith, and Alan W. Nichols -- The preparation of national research council certified reference materials / Scott N. Willie -- CCRMP : preparation and utilization of environmental and geochemical reference materials / Maureen E. Leaver and William S. Bowman -- Development of fortified and unfortified fish CRMs for chlorinated dibenzo-p-dioxins, chlorinated dibenzofurans, and coplanar PCBs, and their use as reference materials for organohalogens / David B. Sergeant and Daniel L. Bolt -- Preparation and certification of a biological reference materials (CARP-1) for polychlorinated dibenzo-p-dioxin, dibenzofuran, and biphenyl congeners / Catherine A. Fraser [and others] -- On the development of certified aqueous reference materials using natural unpreserved lake, river, and rainwaters / Keijo I. Aspila [and others] -- The preparation and validation of generator columns for highly hydrophobic materials / Glenys Foster Roberts and Barry G. Oliver -- Establishing the credibility of environmental laboratories / Donald E. King -- Standard reference materials for the determination of trace organic contaminants in environmental samples / Stephen A. Wise and Michele M. Schantz -- The user's perspective on environmental standard solutions / Gregory E. Pronger and Marilyn A. Melton -- Matrix-based standards and their uses / Lawrence H. Keith -- In-house reference materials as a means to quality assurance : the Canadian wildlife service experience / Bryan Wakeford and Richard Turle -- The use of reference materials and standards in the analysis of environmental samples for organic contaminants / Ian H. Rogers and M. Coreen Hamilton -- Environmental certified reference materials / Scott N. Willie.