Scientist reviews NNR Report

Written by  Sunday, 19 December 2010 04:12
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Wonderfonteinspruit has resulted in contamination of parts of the region with mine spoil and tailings containing heavy metal, uranium and thorium series residues, the latter properly termed Technologically Enhanced Naturally Occurring Radioactive Material - TENORM.

Local concerns about the possible health effects of exposures to this radioactive material resulted in studies by the South African National Nuclear regulator, results and conclusions of which were published in a report Surveillance report of the upper Wonderfonteinspriut Catchment Area T-NNR-10-001 published in 2010.

Dr Chris Busby has been commissioned by Mariette Liefferink, the CEO of the Federation for a Sustainable Environment to briefly review this document.

His report is not a comprehensive analysis of the situation in the area but is intended to point out the main failings in the NNR report and to make recommendations for a way forward in more accurately establishing the scope and degree of the problem of radioactive contamination of the area.

On his expertise to conduct the research, Dr Busby says, "My particular area of expertise is the health effects of internally deposited radionuclides. I have made fundamental original contributions to the science of radiation and health in this area and have published many articles and reports on this issue. I have developed theoretical models of radiation damage at the cell level from internal radionuclides and from high atomic number elements and have also carried out a number of epidemiological studies of populations exposed to internal fission product radionuclides and uranium.

My researches have led me to the conclusion that the health consequences of exposure to internally deposited radionuclides cannot be either scientifically or empirically assessed using the averaging methods currently employed by risk agencies (ICRP, NCRP) based on the Japanese A-Bomb studies and other external high dose exposures. The radioactive element dose coefficients published by the International Commission of Radiological Protection and employed in calculations made by these organisations are unsound since they depend on inappropriate averaging of energy in tissue, as I shall elaborate. This is actually common sense; and it is increasingly seen to be so by many official radiation risk agencies and committees (e.g. IRSN 2005, CERRIE 2004a, CERRIE 2004b), yet the historic weight of the conventional approach to radiation risk (with whole organisational and bureaucratic structures committed to the simplistic historic approaches) has prevented any change in policy in this area. Such an official acceptance of the scientific illegitimacy of the current radiation risk model for internal radiation exposures would have far reaching and financially costly policy implications.

Nevertheless, the present radiation risk model can be used as a baseline for predicting the minimum level of ill health that is likely to result from radiation exposures. In my expert opinion, and for reasons which I shall give, dosimetric analyses and risk calculation based on the current ICRP risk model will give reasonable correct results for external irradiation, but will underestimate the additional risks from internal, inhaled or ingested radioactive material, often by a significant amount (orders of magnitude).

Nevertheless, the present radiation risk model can be used as a baseline for predicting the minimum level of ill health that is likely to result from radiation exposures. "

Recommendations - report extract

  • I recommend that the issue of radiation exposures to the public in this area is addressed properly and scientifically overseen by an independent committee of experts; it is quite clear from what I have seen in the area, and from the little I can gather from the NNR report, that as a consequence of the existence of the contamination in the tailings and spoil heaps there is a serious level of radiation exposure involving uranium and its daughters which will have had and will have health implications.
  • I recommend that the ECRR risk model is employed in such an exercise.
  • I recommend that an epidemiological study of cancer and genetic disease in those most exposed be carried out as a matter of urgency in order to see exactly what has happened and is happening as a result of these exposures.
  • I recommend that those living on these tailings are relocated as a matter of urgency, that all areas containing uranium contamination from mine residues are fenced off and notices placed.
  • I recommend that all efforts are made to reduce dust resuspension from such areas.
Download the NNR's report here: TR-NNR-10-001 - SURVEILLANCE REPORT OF THE UPPER WONDERFONTEINSPRUIT CATCHMENT AREA REV 0 (3mb)