Although the quantification of PCB contaminated mineral oil in electrical transformers may seem simple, based on the limited information gathered and published in the National Implementation Plans already submitted by Parties to the Stockholm Convention, the number of transformers, particularly small distribution units, is so significantly high and their location in the electrical network so wide that unless there is a concerted effort to identify and properly handle them, most countries will not be able to meet their obligation by the targeted date of 2025 for cessation of use.