The problems associated with the toxicity of dispersants at the time of the Torrey Canyon disaster are described together with subsequent developments to reduce toxicity. The problems of laboratory bioassay and its limitations in ecological prediction are reviewed in relation to dispersant concentrations that are reached under field use.

Problems of the use and ecological effects of dispersants in shore cleaning are described in association with practical aspects of safe application and limitations. The author concludes that modern dispersant formulations can be used with minimum ecological risk provided the application is done with care by trained operators. It is stressed that even the most recently developed materials should not be used on areas of vascular plants such as salt marshes and mangroves. The lack of adequate research precludes recommending dispersants to treat oil spillage in freshwater rivers and lakes unless the bodies of water are extremely large.