The complex and related species are found in red blood cells when heme production is inhibited by lead and/or by lack of iron.

The fluorescent properties of ZPP in intact red cells allows the ZPP/heme molar ratio to be measured quickly, at low cost, and in a small sample volume.

[1] In 1974 ZPP was identified as a major non-heme porphyrin formed in red cells as the result of lead poisoning or iron deficiency.,[8] It was already known at this time that non-heme protoporphyrin IX levels were elevated in these conditions, but prior investigators had used acidic extraction methods in their assays that converted ZPP to unbound Protoporphyrin IX.

[12] Heme oxygenase is a cytoprotective enzyme that copes with oxidative stress on a cell and shows higher expression in cancerous tissues.

[10] Increased reactive oxidative species can cause apoptosis in cancer cells and reduce drug resistance when exposed to ZnPP due to loss of the heme oxygenase coping mechanism.

[14] The combination of these two therapies is highly effective in treating cancer in experiments thus far, and is a possible new method for overcoming drug resistance.

[10] However ZnPP have been encapsulated in nanoparticles with specialized coating for drug delivery inside the body.