CANCER MORTALITY IN A RURAL POPULATION LIVING IN THE VICINITY OF A NUCLEAR POWER PLANT

R. Tulbure1, E. Dadulescu2 , R. Gheorghe1

1 Institute of Public Health , 1-3, Dr. Leonte str., 76256 Bucharest, 2 Dolj Public Health Directorate, 6, Constantin Lecca str., 1100 , Romania

In the last period, some minor incidents at the Kozlodui Nuclear Power Plant, placed on the left bank of the , have been notified. The mass media and the population living on the romanian Danube’s bank closed to Kozlodui - having still in mind the Chernobyl disaster - became more concerned about the possible health effects as a consequence of these events. On the other hand from the 1995 the cancer mortality in our country has an ascendant evolution. In this context the public health authority considered as a duty to pay attention to the possible influence of the Kozlodui Nuclear Power Plant on the local population health.

MATERIALS AND METHODS The surveyed area – generic named - include 17 rural localities whit agricultural economic profile, belonging to the , located on the Romanian left bank of the River Danube opposite to the Kozlodui nuclear power plant (figure 1). The whole population is about 88 000 inhabitants of which 14 500 are the children aged 0-14 years. The number of 0-4 years age group living within this area is approximately 4500 (graph 1).

Graph 1. The population figure by sex and age-groups in the observed area ( year 2000)

male female

>75y >75y 60-74y 60-74y 45-59y 45-59y 30-44y 30-44y 15-29y 15-29y 10-14y 10-14y 5-9y 5-9y 0-4y 0-4y 0-4y 5-9y 10-14y 15-29y 30-44y 45-59y 60-74y >75y female 2294 2281 2709 6261 7769 9894 9484 4217 male -2380 -2176 -2543 -6373 -7896 -9878 -7966 -3224

Source of exposure : Nuclear Power Plant (NPPK) from is located on the right bank of the River Danube, opposite to the investigated area ( Figure 1). It is composed of six pressurized light water moderated and cooled reactors (PWRs). The reactors 1 , 2 started operation in 1974-1975, the reactors 3 , 4 in 1982-1984, the fifth in

Figure 1. The area from Dolj county (Romania) under health surveillance

1987 and the sixth in 1990. The liquid effluents are released in the Danube River. The amounts of radioactive materials released from the NPPK reactors during the period 1985 - 1997 are presented in Table 1. As a comparison, the average normalized releases (1985 - 1997) are also presented both for NPPK and for the type of PWRs generally.

Table 1. The discharges from NPPK and average normalized releases (GBq/(Gw a)-1) from NPPK and PWRs generally (1985-1997) [UNSCEAR 1993, UNSCEAR 2000]

Indicators of pollution NPP Kozloduy PWRs Total Average normalized Average normalized (GBq) releases releases (GBq/(Gw a)-1) (GBq/(Gw a)-1) Nobles gases released in 4 361 000 218 000 44 500 airborne effluents Tritium released in airborne Not reported - 2 900 effluents Iodine–131 released in 87.73 4.38 0.55 airborne effluents Particulates released in 37.7 1.88 0.87 airborne effluents Tritium released in airborne 11 690 x) 6 228 22 500 effluents Other radionuclides 28.72 1.43 23 excluding tritium released in airborne effluents x) Reported only for 1997 The two local stations belonging to the Ministry of Health and Family and the Ministry of Environment do the control of nuclear releases in the environment on the romanian territory. In order to detect any changes regarding the pattern of cancer diseases in the interested population we carried out a descriptive study on cancer mortality over the 1994-2000 period. The crude rates and the age standardized cancer mortality rates for both sexes were calculated. Also, the age standardized mortality rates for leukemia in 0-14 years-aged children, over the same period, was computed. The data on the population were collected from the vital statistics and the data on the disease from the local sanitary statistics unit by the personal from the territorial radiation laboratory.

RESULTS Cancer mortality. The annual age standardized cancer mortality rates for whole population (both sex, all ages) for the 1994-2000 period show values between 53.27 and 75/ 100 000, under the values registered at the county and national level (5) (Table 2.). The trend for this period is quite stationary in the surveyed area (graph 3,4). By sex, in the Bechet area the annual average of age standardized rates for 1994-2000 are : 82.3/100 000 (95%C.I. 74.69- 90.21) for males and 45.7/100 000 (95%C.I. 39,72-51.68) for females.

Table 2. The annual standardized cancer mortality rates /100 000 inhabitants (whole population): ASR 1994 1995 1996 1997 1998 1999 2000 Bechet 53.27 72.85 74.98 54.10 68.48 56.55 66.07 Dolj -* 134 129.2 126.3 126.7 126 143.2 county Romania -* 176 164.5 168.2 167.7 197.1 172.2 *No available data

The most frequent cancers that occur in this population are the broncho-pulmonary and the head and neck cancers in males and the breast and the uterus cervix cancers in females. This pattern is the same as the pattern reported from the sanitary statistic for whole the country population (5). GRAPH 3. CANCER ASR IN THE STUDIED AREA GRAPH 4. CANCER ASR AT THE COUNTRY LEVEL

ASR TREND ASR 200 75 TREND

70 190

65 180 SR SR A 60 A

170 55

50 160 1993 1994 1995 1996 1997 1998 1999 2000 2001 1994 1995 1996 1997 1998 1999 2000 2001 year year

Childhood leukemia. The 0-14 years age group in the Bechet area represents about 16.5% of the whole population of this area. Only 2 cases of death from leukemia were registered at this age group: one of them in 5-9 age group and the second in 10-14 age group. The annual average of age standardized rates for this period was 0.99/100000 for girls and 1.37/100000 for boys, lower than the county level for both sex (Table 3).

Table 3. The annual average of age standardized rates/100 000 for leukemia in 0-14 aged group: ASR 1994-2000 Male Female Bechet area 1.38 (95%C.I. –1.88 - 4.66) 0.99 (95%C.I. –6.46 – 8.44) n*=1 n=1 Dolj county 3.23 (95%C.I.0.37 – 6.09) 1.16 (95%C.I. 0.11-2.23) n=16 n=6 *n - number of cases

Environmental exposures. The two local environmental stations did not report any increasing of the environmental discharges in the studied period.

DISCUSSION First of all it is important to underline that the source of exposure (NPPK) and the interested community (Bechet area) are situated in the different countries. From this situation two issues mast be taken into account: S Any occupational exposures to the ionizing radiation related to the plant cannot be involved; S The public and the media suspiciously perceive every incident, even insignificant, which occur to the power plant. Both this issues motivate the interest of the local public health authority for this community. The present study did not found any epidemiological detectable increase of cancers or childhood leukemia among the population living in the Romanian territory nearest the Bulgarian boundaries. Nevertheless, these results are consistent with the results of the other study carried out by the Institute in1994 on the incidence of leukemia in 0-14 years children over the 1980-1992 period in the same area. The results of that study show a lower number of the observed cases than expected: the O/E ratios was 0.98 (95%C.I.: 0.32-2.29) calculated using the childhood leukemia rate in Romania (R.Tulbure, C.May, S. Negoita and al, Leukemia incidence in childhood in the population living the romanian territory closed to the NPPK). Unfortunately, the lack of data on the incidence of leukemia for the 15-25 age group makes it impossible to analyze the disease distribution in this population group too (3). However, the study has been limited by the lack of valid incidence data coming from a cancer register.

REFERENCES 1. Grosche B., Lackland D. & al,1999 Leukaemia in the vicinity of two tritium-releasing nuclear facilities: a comparison of the Kruemmel Site, Germany, and the Savannah River Site, South Carolina, USA, Journal of Radiological Protection vol.19 no.3 pages 243-252 2. Gardner M J & al,1990 Results of case-control study of lekemia and lymphoma among young people near Sellafield nuclear plant in West Cumbria. BMJ 300: 423-434 3. Jensen O M, Parkin D M &al,1991 Cancer registration principles and methods IARC Scientific Publicationss, Lyon 4. Laurier D. 1999 Leucemies chez les moins de 25 ans autour d’ installations nucleaires en France et a etranger: revue des etudes epidemiologiques descriptives , Radioprotection vol.34, n 2, pages 149-176 5. ANNUAL SANITARY STATISTIC REPORT 1995,….2000 Centrul de Calcul, Statistica Sanitara si Documentare Medicala, Bucuresti 6. United Nations Scientific Committee on the Effects of Atomic Radiation 1993. New York 7. United Nations Scientific Committee on the Effects of Atomic Radiation 2000. New York