The safety evaluation of chemicals is in general performed by the government, importer or manufacturer before marketing, and is based on (inter)national legislation. Less is known about the exact products in which chemicals are processed. Even though multiple institutions in the Netherlands are involved with various aspects of chemical safety after marketing, a concrete view on unforeseen effects is lacking. The RIVM aims to improve the system to gain better insight on these effects. Therefore, several stakeholders in this area were brought together to exchange ideas for a more intense exchange of information on signals of possible adverse health effects and on information about existing databases. Actively communication adverse health effects was the focus here, as currently producers are informed after an effect occurred. This report contains an overview of relevant databases, web addresses and contact information to facilitate exchange of information among relevant stakeholders in the field of post marketing surveillance of chemicals. Additionally, three concrete case studies were presented and discussed.