In the course of recent world history, humans have permanently changed the chemical composition of the planet, as human‐made chemical substances become part of the air, water and soil, pervading human and non‐human bodies and upsetting linear imaginaries of past and future. The slow violence of toxic exposure associated with industrial activity and economic growth is a particularly insidious dimension of inequality and exploitation, woven into global and post‐colonial relations of race, class and gender. Yet industrial chemicals underlie and support modern forms of life, and livelihoods, as well as our unsustainable economic system. Such tensions shape how toxicity may be located or ignored, resisted or made habitable, how it may congeal into matters of concern or dissipate into modes of ‘unknowing’. In this introduction, the authors review how recent scholarship imagines and engages with toxic flows. Inspired by research in environmental humanities, geography, history and science and technology studies, as well as scientific disciplines such as eco‐toxicology, anthropologists are searching to grasp the ambivalent ways in which humans ‐ and our non‐human companions ‐ recreate, inhabit, make use of, are exposed to and resist toxic worldings.