Although poisonous substances have been a hazard for the whole of human history, it is only with the development and large-scale production of new chemical substances over the last two centuries that toxic, manmade pollutants have become such a varied and widespread danger. Covering a host of both notorious and little-known chemicals, the chapters in this collection investigate the emergence of specific toxic, pathogenic, carcinogenic, and ecologically harmful chemicals as well as the scientific, cultural and legislative responses they have prompted. Each study situates chemical hazards in a long-term and transnational framework and demonstrates the importance of considering both the natural and the social contexts in which their histories have unfolded.