The number of people registering asbestos-related health conditions is continuing to rise.
But an occupational health expert believes figures in a report issued yesterday do not tell the full story, and doctors need to improve their reporting of work-related diseases.
More than 17,000 people have told the Department of Labour since 1992 that they may have been exposed to asbestos, yesterday's report reveals.
Almost 1000 of those cases have been referred to the national asbestos medical panel for assessment.
The chief adviser for occupational health, Geraint Emrys, said few GPs told their patients about the system for reporting notifiable occupational diseases and even fewer people knew to ask their doctor about it.
Family doctors needed to improve their reporting of work-related diseases or injuries and encourage their patients to do likewise, he said.
The Labour Department yesterday issued two reports into occupationally induced illness - Report on the Notifiable Occupational Disease System 2000-05, and Asbestos Exposure in New Zealand 1992-2005.
Dr Emrys said notifications to the registers were voluntary, but the value of reporting was high.
"Notifying the department of a health problem that may have been caused by work protects not only an individual's health but also the health of their workmates who may be being harmed by the same workplace exposure."
By registering their condition with the department, people gave consent for an investigation to be conducted, he said.
The asbestos report showed that the number of people registering asbestos-related conditions was continuing to rise, but the occupation of sufferers was changing.
Dr Emrys said the medical panel noted that lung cancer notifications were relatively small compared with other asbestos-related medical conditions.
"This suggests that there is an under-reporting of lung cancers associated with asbestos because GPs are automatically linking a person's smoking habits with the cancer and excluding any asbestos-related history.
"That's of great concern to us, as the occupation factor can be important in lung cancers."
Carpenters, plumbers and electricians were responsible for almost 66 per cent of the asbestos cases reported to the department in the past 13 years, Dr Emrys said.
Previously manufacturing workers were the group most at risk.