The Health Council of the Netherlands, which is an independent scientific advisory body established in 1902 `to advise the government and Parliament on the current level of knowledge with respect to public health issues', has recently published an overview report on depleted uranium. The title of the report is `Health risks of exposure to depleted uranium' and it is freely available in both English and the original Dutch language. A brief summary of the report that was published on 16 May 2001 is presented here.

The use of ammunition containing depleted uranium (DU) in Kosovo and elsewhere in the Balkans has provoked disquiet in Europe. In the Netherlands, concern over the release of this material had already been aroused previously following the crash of the El-Al airliner in the Bijlmermeer district of Amsterdam in 1992. It was against this background that the President of the Health Council decided to set up a Committee charged with the task of reviewing the health risks of exposure to DU and the preventive measures required for individuals present in areas where DU has been released into the environment. After reviewing the properties of uranium in general and depleted uranium in particular, and presenting data on the occurrence of the element in the environment and biological tissues, the committee assessed the chemical and radiological health effect of uranium and uranium compounds.

The Health Council Committee concludes that radioactive contamination of the lungs is the principal health risk to be considered in connection with exposure to slightly soluble uranium compounds in the atmosphere. For soluble compounds, the chemical toxic effect in the kidneys is the primary consideration. The toxicological effects are to some extent concordant with those of other heavy metals.

For relevant exposure scenarios the Committee does not anticipate that exposure to DU will result in a demonstrable increased risk of diseases and symptoms among exposed individuals as a result of a radiological or chemical toxic effect exerted by this substance.

Cancer

In view of the fact that DU emits ionising radiation in the form of alpha particles, the induction of cancer, in principle, needs to be taken into account in relation to individuals exhibiting internal contamination with DU. In case of inhalation of slightly soluble DU compounds, attention will in particular need to be focused on the lungs.

The radiation dose caused by incidental exposure to DU in the exposure scenarios considered is limited compared with the radiation dose received during a lifetime of exposure to natural uranium. As at the common levels of exposure to natural uranium a contribution to the induction of cancer in the population cannot be demonstrated, the Committee concludes that the same is true for exposure to DU. This general conclusion is also valid for the appearance of lung cancer and for the appearance of leukaemia after the inhalation of dust containing slightly soluble uranium compounds.

Renal damage

For soluble compounds, the risk posed by exposure to DU is principally of a chemical toxic nature. In the case of increasing exposure, abnormalities will first of all appear in the kidneys. Exposure to small amounts (milligrams) of uranium over short periods will therefore result in changes in the kidneys, which lead to acute, usually reversible, renal impairment. No such dose-dependency has been observed, however, in the frequency of chronic renal disorders among population groups who are chronically exposed to enhanced quantities of natural uranium. Nor have studies involving workers in the uranium industry and ex-military personnel (including the group with shrapnel in the body) to date produced any evidence that uranium can cause renal impairment. Thus the present body of scientific data tends to suggest an absence of irreparable renal damage as a result of the intake of DU in the exposure scenarios considered.

Prevention

Although the risks associated with exposure to DU for the exposure scenarios considered appear to be very limited, the fundamental principle adopted in the fields of industrial and environmental hygiene dictates that unnecessary exposure to a hazardous substance must be avoided and unavoidable exposure be kept as low as reasonably achievable (ALARA).

As far as possible exposure to DU in contaminated areas is concerned (for example in the vicinity of a fire in which DU has been released or in an area where military actions involving the use of DU ammunition have occurred), the Committee considers the strategy for protection laid down in the rules and regulations governing radiation protection to be adequate, both as regards limiting radiological and chemical toxic risks. This means that the first priority is to determine the nature and the extent of the contamination. Has contamination actually occurred? After that, questions should be raised like: If so, how extensive is it and which compounds are involved? Are there fragments of DU in the area? Is there a possibility that windblown DU compounds could be inhaled? And so on. Based on the answers to these questions, one can determine whether it is necessary to impose limitations on access to, and use of, the contaminated area, and whether or not individuals who need to enter the area in a professional capacity (relief workers, for example) should be regarded as radiological workers. This will presumably only be necessary in exceptional cases.

The answers to the foregoing questions are not only of importance for experts and authorities but also for the population in the vicinity of the place where DU has been liberated and for persons who for occupational reasons have to stay there. Open communication can prevent unnecessary anxiety. For this the Committee refers to another recently published advisory report of the Health Council `Local environmental health concerns'.

`Health risks of exposure to depleted uranium' (The Hague: Health Council of the Netherlands, 2001), publication no 2001/13, can be ordered from the Health Council's secretariat, preferably by fax (+31 70 3407523) or e-mail (order@gr.nl), or it can be ordered or downloaded from the Health Council's website (www.gr.nl) where reports are listed in order of publication.