In Tumbes, Peru, despite mass nutritional supplementation and deworming to reduce childhood anemia, its' prevalence has had minimal change compared to other coastal regions. Historic mining in and around the region contaminates the Puyango-Tumbes River Basin, and increases likelihood of chronic heavy metal exposure. The regional government considers anemia a health priority and has solicited support to develop new control strategies. For reasons described above, we aim to characterize anemia and plausible underlying causes in Tumbes, Peru.