Chernobyl Liquidators' Health
as a Psycho-Social Trauma
3. Present health state
and working ability
of the liquidators
This chapter appears to have a rather ambitious aim, namely to review the relevant literature and — on the basis of this review — to give a coherent picture of the present health state of the liquidator-object of this study, who, in brief:
• worked in the zone during any period from the mid-1986 to the end of 1987,
• received an actual (not official!) doze of external gamma-irradiation within the range from several R to several dozen R's (several 0,01—0.1 Gy's in terms of the absorbed dose),
• wore a respirator and did not receive “abnormal” (in Chernobyl sense) dose of internal irradiation;
• was NOT a nuclear (or nuclear-related) professional,
• was NOT a volunteer (as a general rule),
• spent a long enough time in the zone (weeks-months),
• is a male.
I will begin with discussion of the criteria for the selection and assessment of the information on the liquidators' health, and the sources of this information. Then I will briefly present discussion of certain health effects of the Chernobyl Disaster often believed to be most important (cancer, impact upon the reproductive function, consequences of inhalation of Pu-containing “hot particles”) (Ch. 3.1), then I will overview the reported health state of the liquidators (Ch. 3.2). The main emphasis will be laid upon analytical studies of the liquidators' health state as an effect of Chernobyl radiation, psychological and social factors (Ch. 3.3). A psycho-neurological aspect of the liquidators' health will complete the medical picture presented in this chapter.
The task of reviewing the liquidators' present health is quite challenging and complicated for a set of reasons, which will be listed below. The basic question to be answered before attempting to obtain such picture is, to put it explicit: What are the criteria for selection of reliable and relevant information on the present health state of the group of liquidators mentioned above? The problem is that the task of selection of relevant and reliable sources of information, related to Chernobyl medical consequences, is especially hard.
First of all, in literature there is a huge discrepancy as for the medical consequences of Chernobyl in general. The researcher entering this realm finds him/herself in a kind of highly charged field, located between the two poles of extreme opinions, which can be formulated as follows:
— The Chernobyl Disaster has caused death of millions of people, the liquidators included.
— (Opposite to the previous:) As a consequence of the Chernobyl Disaster, only “at least 31 plant workers died from exposure to radiation, and 200 others suffered acute radiation sickness” (Stiling 1996: 426), plus a noticeable increase of children thyroid gland cancer has taken place in the contaminated areas of Belarus (Williams 1994).
In this situation, the first obvious decision to be made is to take into consideration only the data of medical professionals working in the field.
Secondly, medical research of the Chernobyl impact has been a very turbulent process itself. It has been taking place against the background of major changes both in the dominant medical-scientific paradigms in the field, and socio-political, ideological and state paradigms in the USSR/post-USSR societies. That is why research, done and reported in different socio-political moments, represents rather patchy data, and attempts to construct a coherent picture from this research without special precautions can hardly be successful.
Third, as I have already shown and will show further, both in the “in-zone” and in the “post-zone” periods an extremely wide set of factors, ranging from physical to social, could affect the liquidators' health. If in the medical study some of them are not taken into consideration (or simply not mentioned) then it can easily lead to a wrong conclusion, or render the conclusion useless. That is why, in this study, I will try to lay the main emphasis on systematic, clearly and explicitly reported studies.
Following the above principle I will have to treat reviews on this topic with some caution (the reviewer is often simply unable to mention all circumstances of the original research in the review, though some of them may be essential for correct interpretation within a framework different from that of the reviewer), and, hence, I will tend to use primary sources of information rather than secondary.
Forth: Much of research done on the Chernobyl (including liquidators') health is of (purely or mostly) descriptive nature, and it lacks data for its further analysis. Despite such studies do provide some insight into the state of the liquidators' health, their use is limited for the purposes of my study.
Fifth circumstance seems to be obvious: to be regarded as reliable, the paper on radiation medical consequences on should be free of methodological flaws in the research itself and reporting about it. Framework for conducting scientifically credible studies in the field, connected with possible radiation impact, is embraced by “nine essential rules of inquiry” (Gofman 1995), which mainly focus on 3 areas:
— design of comparable exposed and non-exposed groups of people,
— reliability of the dose input, and
— making precautions against the possibility of prejudiced conclusions.
I have discussed the issue of Chernobyl doses in the previous chapter, and here I want to attract attention to the requirement of comparison of the target and control group for reaching a sensible conclusion about impact of a studied factor — the requirement apparently evident and not worth mentioning. In the Chernobyl studies, unfortunately, the lack of reference to a control sample (usually Chernobyl-non-affected, or affected in a controlled way) is a very widely spread defect. I want to illustrate to what consequences it may lead by the following example:
More than 10-fold (!!!) increase of neurological morbidity “of the persons affected by ionising radiation owing to the accident at the Chernobyl NPP” is reported in (Serdjuk et al. 1996b) (cases per 100,000 of the affected):
1991 — 31.8
1995 — 322.4.
However, in the same paper it is noted that in Ukraine cerebral-vascular diseases are among the main causes of disability and death, and their importance increases with time: mortality because of this cause was equal (per 100,000 of the population):
1990 — 209.3
1994 — 252.8,
and that in other countries (Italy, USA) this index is 2—4 times smaller. Of course, the direct comparison of this 2 sets cannot be justified (morbidity vs. mortality, and not identical groups of diseases), the latter figures do give idea about quite a high level of average, “background” neuro-morbidity in Ukraine, and show that the data about the liquidators neuro-morbidity cannot be interpreted without comparison with the respective average figures for the country, or other reference group. Unfortunately, in great many medical papers no comparison with control group is made, and they should be treated with caution.
Next. I'm interested in the present health state of the liquidators, and, hence, as a rule, will omit reports about the health effects observed in the first period after the work in the zone.
Finally, the limited scope of this study puts additional limitations on this survey.
All these circumstances form a rather strict “sieve” for selection of the sources of information for this study.
In the light of the above requirements, a series of works of Simonova et al. (1995, 1998) and Amirazjan et al. (1996, 1997, 1998) has attracted my special attention for the following reasons:
1. In terms of the general picture presented, they are in good qualitative agreement with the other data related to the issue. The results were published in and discussed in recognised journals and at conferences in this field, this circumstance endorsing their scientific validity. The main findings of this series of papers are supported by the results obtained by other researchers from different institutions and countries, and much of indirect evidence.
2. These are a series of systematic studies, characterised by:
— complex approach (not only complex medical examination was done, but also was it complemented by psychological examination, studies of medical archives, reference to factors of social environment, etc.);
— usage of integral parameter, namely, that of working ability, to characterise the state of the health; it makes possible practically important comparisons with non-liquidators' populations;
— presentation of the data on the liquidators in comparison with a reference group that is sensibly designed and explicitly described;
— analytical — rather than merely descriptive — approach; the sequence of papers seems to be remarkable for its logic;
— attempts to interpret the results not only considering the (possible) effects of the in-zone (including radiation) factors but also those of post-zone factors.
It should be noted that this series of research papers is not “ideal” and contains some deficiencies common for this field (I will point them out), but unlike arguable majority of research reported, the drawbacks do not hinder the interpretation of the data and conclusions presented.
Design by: M.Opalev
Studio ARWIS Kharkov, 2001