Microplastic pollution is a major challenge of the 21st century. Humans ingest, inhale, and absorb microplastics and their toxic products, which are linked to many diseases. However, detecting these exposures to establish causality is difficult, and traditional epidemiological approaches are unfit for this pressing concern. I introduce the concept of genomic epidemiology, exploiting the fact that many microplastic-related chemicals are DNA-damaging. Postulating that microplastic exposure can be detected using genomic readouts of mutations caused by their constituent DNA-damaging chemicals, my laboratory will define and examine specific microplastic-induced mutagenic imprints to equip traditional approaches with permanent, quantifiable genomic exposure records. The approach has far-reaching applications that could transform harmful exposure detection across species to guide global policy on managing risk, prevention, and mitigations of the harms of microplastics and other pollutants.