1. A system for identifying defunct nodes, the system comprising: a memory; a processor in communication with the memory, the processor being configured to perform a method comprising: generating a lineage graph for a data processing system, the lineage graph containing two or more nodes, the lineage graph identifying a flow of data through the data processing system; identifying a first node in the lineage graph, wherein the first node is an active node that processes protected health information about one or more individuals; determining, from the metadata for the first node, a maximum amount of time that protected health information may be stored without being processed; determining an amount of time since the first node last processed the protected health information; comparing the amount of time to the maximum amount of time; determining, in response to the comparing, that the first node is a defunct node; identifying a second node in the lineage graph, the second node being a passive producer node; determining a second amount of time, the second amount of time being an amount of time since data in the second node was last updated; comparing the second amount of time to a threshold; determining, in response to comparing the second amount of time to the threshold; that the second node is operational; identifying a third node in the lineage graph, the third node being an active transformer node that has first and second inputs; determining that the first input for the third node is defunct; determining that the second input for the third node is operational; determining, based on the first input being defunct and the second input being operational, that the third node is tainted; generating a report for the data processing system, the report including an indication that the first node is defunct, the second node is operational, and the third node is tainted, the report further including an explanation of why the first node is a defunct node; adding an indication that the first node is a defunct node into metadata of the first node, the indication that the first node is a defunct node including the explanation; providing the report to a user; prompting the user to determine whether to remove the first node from the data processing system; receiving, from the user, an indication that the first node is to be removed from the data processing system; and removing the first node from the data processing system.