ECDIN (Environmental Chemicals Data and Information Network) has been created within the framework of the environmental research program of the Joint Research Centre of the Commission of the European Communities in Ispra(Italy). ECDIN is a factual databank. All data fed into the databank have been evaluated by experts. They cover a wide variety of parameters and properties for the evaluation and control of environmental risks associated with chemicals. ECDIN is based on the identification data for more than 120,000 chemicals in the European Inventory of Existing Substances (EINECS). For this first CD-ROM edition, about 1,700 of the best described data sets have been collected. These data will be updated by the Joint Research Centre. The substances in the database are covered under the following headings: - Identification, - Chemical structure information, - Chemical and physical data, - Analytical methods, - Use of the compound, - Toxicity, - Occupational health and safety, - Odour and threshold values, - Ecotoxicity and environmental behaviour, - Civil protection. All fields are searchable via full text search or via indexes. Hardware requirements: IBM PC or compatible, MS DOS 3.1 or higher, hard disk with at least 2 Mb free, 640 Kb RAM, EGA, VGA or Hercules graphics card, CD-ROM player.