Abstract Anaerobic adhesives polymerise rapidly, by a free radical mechanisms, when confined between two closely fitting metal surfaces to form tough solvent and heat resistant material. Anaerobic adhesives are typically based on methacrylate monomers and are predominantly used for the sealing and retaining of metallic objects. Transition metal ions on the substrate surface play a key role in the cure chemistry, catalytically decomposing hydroperoxides, such as cumene hydroperoxide, present in the adhesive to generate free radicals capable of initiating polymerisation. This study investigates the ability of lower and higher oxidation states of copper and iron to decompose cumene hydroperoxide, and also investigates the influence of saccharin, maleic acid and adhesive accelerators on this process.