During the period 1958-1964, research expanded the Porphyrin field by showing ether-soluble porphyrins in both healthy humans and animals, prompting refined chromatographic separation and enabling systematic classification of porphyrin species in health and porphyria. This era also established erythropoietic protoporphyria as a distinct porphyria characterized by solar-induced urticaria due to protoporphyrin accumulation, guiding reclassification and the development of diagnostic biomarkers and understanding of photosensitivity pathology. Epidemiological reports of cutaneous porphyrias in Turkey highlighted environmental factors and regional clustering, while studies linking hexachlorobenzene intoxication to acquired porphyria in both humans and rats emphasized xenobiotic stress as a porphyrin trigger and spurred investigations into hepatic porphyrin handling and industrial exposure risks. These converging threads laid a foundation for an integrated view of porphyrin metabolism shaped by genetics, environment, and exposure. Historical Significance: The era catalyzed a metabolism-centric view that linked porphyrin species with disease phenotypes, enabling robust diagnostic strategies, biomarker development, and an appreciation of environmental and toxicant influences that guided future porphyrin biology and clinical management.