Over the past decade lead contamination science emerged into Peruvian political discourse in the context of national anti-mining protests. The scientific documentation of the metal lead in human tissue, particularly that of children, provides continued evidence of Peru's national health disparities and the bio-political implications for further economic development of the country's mineral sector. My research interrogates the dimensions of this social debate through the lens of representational politics. Drawing from field sites in the Andean mineral zone and the port of El Callao, I will examine how lead becomes both an object of science and a socially salient political actant. To do this I will conduct research with Peruvian and international scientists who study lead, as well as social actors like affected community members, NGO workers, activists, and policy makers who politicize these scientific findings into a socially relevant story that can have political effects. From preliminary research my hypothesis posits that representing the medical and social effects of mining through scientific measurements of lead provides new political possibilities for socially and economically marginalized communities, as well as related anti-mining activism. Yet because international epidemiological studies correlate lead intoxication with cognitive impairment, the representation of lead in forms of media and political mobilizations in Peru often link the contaminant's effects to biomedical and social anxieties related to education, behavior, and violence. Historical uses of biological determinants to explain racial and cultural difference among Peru's diverse ethnic groups seems to resonate with these depictions of lead as a determinant for impaired social behavior and moral development. Thus my research asks how lead becomes a political tool, but also how this political tool itself comes to represent impacted communities and affects representations of Peru's poor "as usual"?