Health conditions among workers who participated in the cleanup of the Chernobyl accident

Health conditions among workers who participated in the cleanup of the Chernobyl accident

Z. Kamarli

& A. Abdulina

In Kyrgyzstan, the health status of the people who were exposed to radiation from the Chernobyl ac- ciden t and took part in the cleanup (or "liquida- tion") of the site has been monitored since 1991.

Clinical observation of children born in families of the cleanup workers ("liquidators") of the acci- dent consequences after their return from the acci- dent zone began in 1992. For the last two years medical care has been provided for all the people who were in other radiation disaster zones (Semi- palatinsk, Chelyabinsk region, etc.), and a special 3-level registry has been established for these patients.

In 1992, the Interdepartmental Board of Ex- perts, a government agency, was established for the evaluation of diseases and their relation to the work done in the zone of high-level radiation, in those persons who had been subject to radiation effects after the Chernobyl accident. The staff of the Board consists of medical specialists from dif- ferent fields and representatives of social security, trade unions, and the Union Chernobyl public organization. Professor Z. Kamarli was appointed Chairman of the Board.

By 1 January 1995, 2 093 people including 407 children born after their parents' work in the Chernobyl accident zone, were being followed up through the registry. In addition, 24 evacuees including 7 children from the Chernobyl accident zone, 3 persons who had resided in the Techa River basin in Chelyabinsk province ("oblast") for a long time, and 3 servicemen who took part in the nuclear tests in Totski, Orenburg province, were also registered. At present the number registered is approaching 3000, mainly due to improved regis- tration in the sonth of the republic.

In Kyrgyzstan, uranium has been mined in a number of regions, and radioactive waste deposits are found around these populated areas. More- over, some towns and villages bordering China have been subject to the effect of radioactive dust during the nuclear tests at Lob Nor. Considering these circumstances, an increase in the number of people likely to be registered can be expected.

Meanwhile, there is no regular, clinical examina- tion of the population in those regions, chiefly

aKyrghyz Oncology and Radiology Research Institute, Bishek, Kyrgyzstan.

W/d h/thststis; quart.,49(1996)

because of financial difficulties and the absence of the only programme which aims to lessen the severity of radiation consequences.

Nevertheless, in the current year, with the fi- nancial support of our partners from the Kansas University Medical Center (United States of Amer- ica), medical examinations of the residents of Mailuu-Suu town in the south of Kyrgyzstan were carried out. Around this town there are about 20 waste deposits maintained without due precau- tions. Nearly 5500 people including 2100 chil- dren were examined.

The preliminary results of this study showed that among people who considered themselves healthy more than 50% of the adults and 38% of the children suffered from various diseases. Medi- cal care was provided for some of these newly dis- covered patients.

Of 1 688 adult patients included in the registry, 1 584 (94%) have undergone a prophylactic medi- cal examination. Of these, only 627 (39.6%) were healthy, the rest (957 or 60.4%) had various dis- eases and needed medical treatment.

An analysis has shown that the number of pa- tients among Chernobyl accident cleanup workers increases each year (from 54.5% in 1991 to 60.4%

in 1994) and that the number of invalids among them increases in an almost geometrical progres- sion (from 2.3% in 1991 to 20.6% in 1994). This indicates serious disorders in the organisms of peo- ple who were subjected to radiation effects while working in the accident zone. These disorders re- sult in disability, despite the therapeutic measures applied each year. However, it cannot be denied that there are shortcomings in the medical care dispensed to these patients.

Fig. 1 shows the increase in number of diseases in the followed-up population. When comparing these data with corresponding figures for the re- public as a whole, it was observed that the inci- dence rate among the cleanup workers of the Chernobyl accident site was nearly 3 times that in the rest of the population, although the rate of increase of the morbidity rate among the cleanup workers showed a tendency to slow down. How- ever, a significant improvement in registration, es- pecially in the south of the republic, is likely to result in an apparent increase in the followed-up population.

Fig. 2 shows the incidence rate of various disor- ders among the cleanup workers and a comparison 29

7 times higher than in the rest of the population.

For diseasesof the digestive syste m,the incidence rate is 5.6 tim eshigher among the clean up work ers than in the general populati on.

Diso rders of the en docrine and immune sys- tems occu r rather ofte n in persons su bjecte d to ir radi ation. These diso rd ers occu r more than 18tim es more fr equently among th e cleanup worke rsthan in therest of the Kyrgyzpopulation.

Can cer has been detected nearly 4 times as fre q uen tlyin those su bjecte d to irradi ation asin the populat ionasawhole.

Analysis of mortality rates (T able 1) durin g a 3-year period shows that su icides were the most com m on cau seofdeathamon g people exposed to radiation. Abouta quarter of all death s were sui- cid es, and if we were to consider the taking of massive dosesofalcohol asa type of suicid e ,then thisfigurewou ldincrease stillmore.

Owing to the impossibility of calculati ng pre- cise, individual doses of radiat ion , it may be as- sumedthatthe morbiditywas caus ed by small doses of ionizing radiatio n. The psychosocial stress ef- fects,manifestations ofwh ich are various and la- tent for a long time,are ad ded to th at. The treat- men t has a temporary an d some times very slight effect,makingit necessarytosearc h for new waysto provid e therapy and rehabilitation for these fol- lowed-u p patients.

In Kyrgyzstan ,thereis sign ifican texperie n cein therapyand rehabili tationof patients using alpine climatotherapy, a method known for its effective- ness.Thus,th e alpine base at Tuya-Ashu (3200 m above sea level ) wasused jointlywith the Institute ofCard io lo gyfro m 1992through 1995for the re- ha bilita tion of the Chernobyl acciden t cleanu p workers. The cou rse of treatment lasted for 24days. Co nsid eringthat only20patien ts received such treatmen t, so far it is too early to draw a co n clusion . Howeve r, the positive influence of high-altitudeclimato therapyon the fu nc tionalin- dicators of the respiratory, card iovascular and im- munesystemshas beenobserved.

3441

Incidencerateamong cleanup workers-Taux parmi lepersonnelaffecte au neltoyagedu site

Totalincidencerate- Taux pourI'ensembledela population

D

1991 942

o

5000 40000 35000

25000 20000

10000 30000

15000

45000 - . - - - ,

Fig.1

Increasein diseaseamongcleanup workers afterthe Chernobylaccident,Kyrgyzstan,1991-1994 Augmentation desmaladies chezle personnel ayant partlclpe

a

Tchernobyl,Kirghizistan, 1991-1994

Fig.2

Structureof morbidity incleanup workers:comparisonwith averagerates per100 000, Kyrgyzstan

Structuredelarnorblditechezlepersonnel chargedela remiseen etatdusite:comparaison aveclestaux moyens pour100 000 personnes,Kirghizistan

o 500 1000 1500 2000 2500 3000 3500 4000

1. Diseasesof the nervoussystemand mentaldisorders- Maladiesdusysteme nerveuxettroubles mentaux

2.Diseases ofthe digestivesystem- MaladiesdeI'appareil digestif 3. Disordersofthe endocrineandimmune systems.Maladies

endocriniennes ettroublesimmunitaires 4.Cancer

withthe average ratesper100 000for the popula- tion asa whole . The left bar sh ows the incidence rate amo n g the cle an u p workers, an d the one on the right, the average ratesfor th e wh o le rep u blic.

For diseasesof the nervous system and men tal dis- orders, the rates among cle anup workers are

2 3 4

Conclusions

1. The establishment of the registry of persons su bj ected to radiatio n contri bu tes tothe detec- tion of illness among them, and their timely treatment.

2. Theregistrydata for Kyrgyzstan sh ow that mor- bidity am on g the observed population is in- cre asin g. Diseases of the nervous system are mostfreq uent,followedbydiseasesofthe diges- tive, r spiratory and en docr in e syste ms. The immune is ve ry ofte n affected, too.

3. The mor tality rate among cleanup workers of the Ch mobyl accident site is high. Suicide is oneofthe main causes ofdeath in thispopu la- tion.

30 Rapp.trimest.statist.sanitmono;49(1996)

Table 1

Maincauses ofdeathamong theChernobylAtomic Energy Stationaccident cleanup staff,1989-1994 Tableau 1

Principalescauses de ceces parmile personneldela centralenuclealredeTchernobylattecte

a

Cause Numberofdeaths - %

Nombrededeces

Suicide 16 23.2

Cardiovascular diseases-

Malad iescardio-vasculaires 12 17.4

Alcoholpoisoning - Alcoolisme 10 14.5 .'i

Cancer 5 7.25

Otherdiseases- Autres maladies 26 37.65

Total 69 100.0

4. High-altitud e climatotherapymay become one ofthe auxi liarymethods for the treatm en tand rehabilita tio n of people subjected to rad iation.

Summary

People who tookpart in theChernobylacc ident cleanup have been registered upon theirreturn to Kyrgyzstan since 1991,andtheir childrensinc e1992.Later,citizens affectedby theSemipalatinskand Chelyabinskcontam- ination incidents were inc luded for registration and healthcare purposes. The effectsof the nuclearwaste depositories inthe Mailuu-Suuregion were examin ed with the assistance of the Kansa s University Medical Center(United States of America).

Alltheseinvestigations ofaffectedpeop le indicate ap- parentincreasesin a numberofsymptoms and illnesses when comp ared to the rest ofthepopulation. Sample sizes rangedfrom several hundred to several thousand. Above-normalradiationlevelsand/or the stress and fear ofliving in contaminated areas can lead to significant increasesin nervous disorders,cardiovasculardiseas- es and otherproblems.The most significant increase wasinthe suicide rate.

Wldhlthstsust.quart.,49(1996)

Resume

Conditions sanitaires parmi les membres du personnel ayant participe au nettoyage apres /'accident de Tchernobyl

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