Health Monitoring

The Ministry of Forestry's programme to eradicate the white-spotted tussock moth used aerial Btk spray between October and December 1996 throughout the eastern surburbs of Auckland, followed by continued spraying in a more limited area until April 1997. Also, some properties in infested locations were ground sprayed with Btk. Before spraying started in 1996, the Ministries of Forestry and Health commissioned Auckland Healthcare Services (A+) to carry out a Health Risk Assessment (HRA). This was updated in September 1997. (Link to HRA) The Health Risk Assessment found that Btk commercial sprays are safe for people exposed to spraying. Further, it found:

  • No miscarriages or premature deliveries associated with Btk
  • No bacteria causing allergy
  • No increased attendance at Baycare health centre as a result of spraying
  • No increased measles or meningococcal disease A Medical Advisory Group is examining the reported health events from the 1996/97 spraying to assist individual risk management.

The Government commissioned a health surveillance programme during 1997 to 1999. This is monitoring for any health effects which might arise following the spraying. It has four main components:

  1. Doctors throughout the eastern suburbs have been asked to report to the Medical Officer of Health any illnesses they consider to be associated with exposure to the spraying
  2. Patterns of selected health problems within some local medical practices are being examined by those doctors to detect any differences from usual patterns
  3. Health experiences within the spray zone are being checked, using existing appropriate health information systems eg the congenital anomalies register
  4. A register is being compiled of people living in the zone which had greatest exposure to spraying. This has been lodged in National Archives for use in any future long term studies into health effects

Residents of the former spray zone can still make contact with the Ministry of Agriculture and Forestry’s independent medical advisor if they have any health concerns or questions. They should first call 0800 76 5000.

Page last updated: 30 April 2008