Cancer study uncovers job risks

Female health workers are more likely to die from leukaemia, teachers from breast cancer and restaurant workers from lung cancer, new research has found.

Otago University researchers analysed the cases of 7200 New Zealand women who died of cancer between 1988 and 1997. Occupational data was taken from death certificates.

They found leukaemia death rates were significantly increased in health professionals. Ovarian cancer and Hodgkin's disease were also slightly higher.

In an article published in today's New Zealand Medical Journal, they say there is conflicting evidence of an association between leukaemia and exposure to some antineoplastic drugs - used to slow or stop the growth of tumour cells - in a clinical setting.

Teachers had a significantly increased risk of death from breast cancer, an association found in other studies.

They also had an increased risk of colon cancer, which had been associated with sedentary jobs and a lack of exercise.

Restaurant workers had a significantly increased risk of death from lung cancer, as seen in other studies, and thyroid cancer.

The thyroid cancer finding was unusual and probably due to chance, the researchers said.

Clerical workers had a significantly increased risk of death from pleural cancer (in the membranes on the lungs) and increased risks for cancers of the bladder, brain, colon and rectum.

Between 2 and 8 per cent of all cancers are estimated to be caused by occupational exposure, such as asbestos. Women are at the lower end of the scale.

The researchers said between 24 and 59 cancers a year in New Zealand women might be caused by exposures in the workplace.

The study was the first major examination of cancer mortality for women by occupation, they said.

"With increasing numbers of women entering the paid workforce ... it is becoming increasingly important that national health records [mortality, cancer registry and hospital discharge data] are routinely examined for possible associations with occupation."

Statistics NZ has stopped noting occupations on death certificates, so the data is no longer easily available. Nor does the cancer registry make a note of occupation.

- © Fairfax NZ News