The country's asbestos exposure register has been shut down.
WorkSafe has run the voluntary register for several years, but it "was not completely reliable" as it relied on people self-reporting, the agency said.
The register was not used for healthcare follow-up or compensation, only for WorkSafe research.
"As agencies have improved their own data collection, WorkSafe is able to get data from other agencies. This means the [register] is no longer needed."
Privacy rules also meant the Crown regulator was not able to easily share the data with anyone else.
"It is also unusual for WorkSafe to hold information on individual worker health," it added.
The register has not been receiving exposure reports since December.
What data is on there is being kept.
"We... are working on a solution for how this information will be managed in the future", WorkSafe said.
In 2017, the register was seen as "valuable".
"If you believe you have been exposed to asbestos, you can put your details on the WorkSafe New Zealand Asbestos Exposure register," the WorkSafe website said. "You will receive information on asbestos while the register provides WorkSafe with valuable information to help with the management of potential exposure to asbestos."