Internet portals for chemists.

This paper is to give an overview of freely available subject services providing information for chemists on the Internet. An attempt is made to differentiate between portals and other kinds of resources encountered on the Web. A definition of portals is given. Subject collections of general chemistry, analytical chemistry, environmental research, toxicology and patents are described. Internet chemistry portals can be regarded as a valuable addition to the traditional print and online information sources used by chemists