Topics in Toxicology Toxicology is a science that stands at the intersection of several interests and disciplines. These intersecting forces are by means all scientific since some are legal and some are commercial. All have valid things to say about the conduct and interpretation of toxicity experiments. The practising toxicologist must bear all these sometimes conflicting forces in mind as he carries out his duties. This is especially true, of course, of the toxicologist in industry. Toxicology is also a field in which contract research particularly flourishes and a number of major contract research companies have established over the years a reputation for contributing usefully to the practice of this skill. These contract research organisations are particu- larly favoured to develop an appreciation of the problems of the in- dustrial toxicologist, since it is very common for such a company to service the toxicological needs of companies in several sectors of industry producing new chemical compounds, and the contract research company, therefore, is aware of a wider diversiy of problems than probably affects a single toxicologist in one industry.