Environmental toxicology is the study of the ecological effects of anthropogenic substances released into the environment. It is a relatively diverse field addressing impacts to aquatic and terrestrial organisms and communities. The determination of potential risk associated with toxic agents is of interest to government regulators, industry, researchers, private organizations and citizen groups. In assessing the ecological risk associated with a chemical stressor, it is important to establish linkages between likely exposure concentrations and adverse effects to ecological receptors. To do so requires access to reliable information resources. The proper application of such data requires familiarity with the scientific literature and keeping abreast of new and emerging issues as well as state-of-the-art research findings and methods. In addition, an understanding of government regulations as they relate to environmental issues is also of primary interest. The advent of the Web has made these tools accessible at computer desktops. This review focuses on currently available free Web resources related to environmental toxicology, specifically those which address available empirical data sources, predictive tools and publications of interest such as standard test methods, guidance documents and governmental regulations.