Use of Mechanistic Information in Risk Assessment Proceedings of the 1993 EUROTOX Congress Meeting Held in Uppsala, Sweden, June 30–July 3, 1993

M. Pliftski Institute of Oceanography, GdaJisk University 46 Pilsudskiego Av. 81-378 Gdynia, Poland 2 The Baltic Sea with 366,000 km is only 0. 1% of the world's oceans but nevertheless, unique in many ways. The Baltic Sea is the largest area of brackish water in the world. As a formation of nature, it is a sea that in many ways resembles a lake. This makes its flora and fauna interesting and well adapted to the brackish water environment. The recent stage of biocoenosis composition is influenced by several features. Historically, during the last glaciation, when the Baltic was sometimes a huge marine bay and sometimes a large, freshwater lake, several ecosystems developed and were successively replaced. The flora and fauna composition of those previous biocoenosis was discovered from the geological layers corresponding to the Yoldic Sea, the Ancylus Lake and the Littorina Sea periods. Recently the marine influence has come from the North Sea water inflow, which greatly affects the salinity of the deep water. The freshwater influence comes from the fluvial water which gives the surface layer a lower salinity value. Salinity in the Baltic regions varies greatly - Gulf of Bothnia 2-4%0, the central Baltic proper 7-13%0, the Kattegat 15-300/00 in the surface water and 32- 34%0 in the bottom water, the Skagerrak 20-300/00 in the surface and 32-35%0 in the bottom water.

Baltic Sea Pollution.- Ecology of the Baltic — Introduction.- Presence and Sources of Pollutants in the Baltic Sea.- Interrelationship Between Eutrophication and Effects of Pollutants.- Effects of Toxic Metal Pollutants on the Ecology of the Baltic Sea.- Effects of Persistent Organic Pollutants on Biota in the Baltic Sea.- Human Health Risk Assessment and Risk Perception Related to the Baltic Sea.- Contact and Respiratory Sensitisation.- Immunoregulation of T Cell-Mediated Skin Hypersensitivity.- Test Methods for Contact Sensitisation.- Test Methods for Respiratory Sensitisation.- Newer Approaches to the Evaluation of Sensitisation Phenomena.- Risk Assessment of Sensitizing Agents.- Developmental Toxicity.- Nuclear Retinoic Acid Receptors and Regulation of Gene Expression.- The Role of Retinoids in Normal Development and Retinoid-Induced Malformations.- Retinoid Teratogenesis: Toxicokinetics and Structure-Specificity.- The Neurochemical Effects of PCB Exposure are Age-Dependent.- Risk Estimation and Primary Prevention of Birth Defects.- Role of Mechanistic Studies of Toxicity in Risk Assessment.- The Role of Mechanistic Studies in Understanding Target Organ Toxicity.- Rational Species Extrapolation of Toxic Effects.- Predicting the Toxic Dose or Concentration. Is there a Difference?.- The Role of Investigative Toxicology in Pharmaceutical Industry.- Mechanisms of Metal Toxicity.- Metal-Induced Autoimmunity.- Genotoxic Effects of Metal Compounds.- Toxicokinetics of Drugs.- The Importance of Exposure Measurements in Risk Assessment of Drugs.- The Impact of Genetic Polymorphisms in Risk Assessment of Drugs.- Kinetic Analysis Using Positron Emission Tomography.- The Application of Modelling in Toxicokinetics.- Alterations in Kinetic Parameters Resulting in Modification ofToxicity.- Mechanisms of Carcinogenicity and Risk Assessment.- Importance of Genetic Alterations in Tumour Development.- Transgenic Mouse Models in Chemical Carcinogenesis Studies.- Cell Proliferation and Cell Death in Rat Liver Carcinogenesis by Chemicals.- Use of Mechanistic and Other Data in Identifying Carcinogens: A Review Based on the IARC Monographs Programme.- Late Manuscripts.- Developmental Toxicity — Magnitude of the Problem.- Health Problems Related to Respiratory Sensitisation.- Young Scientists Poster Award.- Neonatal Exposure to the Organophosphate DFP Induces Changes in Behaviour and Muscarinic Receptor Density in the Adult Mous.