Because of concerns by residents that illnesses might be due to dioxin exposures from the former Ivon Watkins-Dow plant in New Plymouth, the Ministry proposed a serum dioxins study of selected residents who live or did live at Paritutu, the nearest suburb to the plant.
Non-occupational health effects in the New Plymouth population
The aim of the survey is to determine the level of dioxin exposure in comparison with the levels found in the Ministry for the Environment’s background population study.
The final report of a study to investigate historical exposure to dioxin among current and former residents of the New Plymouth suburb of Paritutu was released on 10 March 2005.
The study, conducted by the Institute of Environmental Science and Research (ESR), was to determine whether residents who lived close to the former Ivon Watkins Dow (IWD) agrichemical plant while the herbicide 2,4,5-T was being made from 1962 to 1987 had dioxin levels higher than other New Zealanders.
You can download the final report below in Word format.
- A Study of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Exposures in Paritutu, New Zealand - Final Report, with Errata (Word, 3 MB)
- Appendix A: New Plymouth, Paritutu Community Dioxin Exposure Assessment Study (PDF, 1,63 MB)
- Appendix B: Multipathway Assessment of Exposures from Dioxin Releases in the Paritutu Area (PDF, 1,78 MB)
- Appendix C: Geospatial Modelling of Soil TCDD (PDF, 463 kB)
- Appendix D: Estimation of exposures associated with 2378-TCDD in soils, and possible current serum residues from those exposures. (PDF, 255 kB)
- Appendix E: NZ 2378-TCDD Toxicokinetic Model (PDF, 333 kB)
- Appendix F: Preliminary Review of Pharmacokinetic Modeling Issues for Estimating Long-Past 2,3,7,8-Tetrachloro-Dibenzo-Dioxin Exposures in New Zealand (PDF, 197 kB)
- Appendix G: Controls Approach (PDF, 82 kB)
- Appendix H: Interpretation of blood results (PDF, 147 kB)
- Appendix I: Interlaboratory Quality Assessment on Levels of PCBs, PCDDs and PCDFs in Human Milk and Blood Plasma (PDF, 487 kB)
- Appendix J: Carton milk and other intake changes (PDF, 55 kB)
- Appendix K: Statistical Assessment Revised (PDF, 99 kB)
- Appendix L: Dioxin Questionnaire (PDF, 244 kB)
- Appendix M: Questionnaire Paritutu Serum dioxins Study (PDF, 265 kB)
- Appendix N: Analysis of Polychlorinated Dioxins and Furans, and PCB Congeners in Blood Serum by Hrgc/Ms - AXYS Analytical Services Ltd. (PDF, 87 kB)
- Appendix O: Individual Dioxin and PCB Serum Results for the Paritutu Dioxin Study 2004 (Phase II, Parts 1 & 2), with Errata (PDF, 46 KB)
- Appendix P: Summary Description of Candidate Selection Model (PDF, 62kB)
Important: Ministry of Health disclaimer
The data and analyses contained in A Study of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Exposures in Paritutu, New Zealand have been supplied to the Ministry of Health by the Institute of Environmental Science and Research Ltd (ESR).
The Ministry of Health cannot confirm the accuracy of the data and the analyses, and accepts no liability or responsibility for any acts or omissions, done or omitted in reliance, in whole or in part, on the data or the analyses.
2005 Peer Reviews
- Professor Neil Pearce's comments on: Fowles et al. A study of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposures in Paritutu, New Zealand (PDF, 13 KB)
- Preliminary Review of Pharmacokinetic Modeling Issues for Estimating Long-Past 2,3,7,8-Tetrachloro-Dibenzo-Dioxin Exposures in New Zealand, Dale Hattis (PDF, 139 KB)
- Peer review of the Report to the New Zealand Ministry of Health – A Study of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Exposures in Paritutu, New Zealand, Erik Dybing, Norwegian Institute of Public Health (PDF, 28 KB)
2006-7 Peer Reviews
Following a report by forensic accountant,John Leonard, which was broadcast on TV3 as part of the documentary “Let us Spray”, further independent peer reviews were carried out.
- Marie Haring Sweeney's comments on: A study of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposures in Paritutu, New Zealand (PDF, 446 KB)
- Allan H. Smith's comments on: A Study of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Exposures in Paritutu, New Zealand (PDF, 50 KB)
- C Frampton's comments on: A Study of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Exposures in Paritutu, New Zealand (PDF, 26 KB)