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N A Koshurnikova

Publications and source records attributed to N A Koshurnikova.

At least 19 recordsLinked to original sources
PubMed2004

Lung cancer in Mayak workers.

The cohort of nuclear workers at the Mayak Production Association, located in the Russian Federation, is a unique resource for providing information on the health effects of exposure to plutonium as well as the effects of protracted external dose. Lung cancer mortality risks were evaluated in 21,790 Mayak workers, a much larger group than included in previous evaluations of lung cancer risks in this cohort. These analyses, which included 655 lung cancer deaths occurring in the period 1955-2000, were the first to evaluate both excess relative risk (ERR) and excess absolute risk (EAR) models and to give detailed attention to the modifying effects of gender, attained age and age at hire. Lung cancer risks were found to be significantly related to both internal dose to the lung from plutonium and external dose, and risks were described adequately by linear functions. For internal dose, the ERR per gray for females was about four times higher than that for males, whereas the EAR for females was less than half that for males; the ERR showed a strong decline with attained age, whereas the EAR increased with attained age until about age 65 and then decreased. Parallel analyses of lung cancer mortality risks in Mayak workers and Japanese A-bomb survivors were also conducted. Efforts currently under way to improve both internal and external dose estimates, and to develop data on smoking, should result in more accurate risk estimates in the future.

Adolescent↗
PubMed2003

Lung cancer mortality among nuclear workers of the Mayak facilities in the former Soviet Union. An updated analysis considering smoking as the main confounding factor.

A new analysis of lung cancer mortality in a cohort of male Mayak workers who started their employment in the plutonium and reprocessing plants between 1948 and 1958 has been carried out in terms of a relative risk model. The follow-up has been extended until 1999, moreover a new dosimetry system (DOSES2000) has been established. Particular emphasis has been given to a discrimination of the effects of external gamma-exposure and internal alpha-exposure due to incorporated plutonium. This study has also utilized and incorporated the information from a cohort of Mayak reactor workers, who were exposed only externally to gamma-rays. The influence of smoking as the main confounding factor for lung cancer has been studied. The baseline lung cancer mortality rate was not taken from national statistics but was derived from the cohort itself. The estimated excess relative risk for the plutonium alpha-rays was 0.23/Sv (95%CI: 0.16-0.31). The resulting risk coefficient for external gamma-ray exposure was very low with a statistically insignificant estimate of 0.058/Sv (95%CI: -0.072-0.20). The inferred relative risk for smokers was 16.5 (95%CI: 12.6-20.5).

Cohort Studies↗
PubMed2003

Cancer mortality risk among workers at the Mayak nuclear complex.

At present, direct data on risk from protracted or fractionated radiation exposure at low dose rates have been limited largely to studies of populations exposed to low cumulative doses with resulting low statistical power. We evaluated the cancer risks associated with protracted exposure to external whole-body gamma radiation at high cumulative doses (the average dose is 0.8 Gy and the highest doses exceed 10 Gy) in Russian nuclear workers. Cancer deaths in a cohort of about 21,500 nuclear workers who began working at the Mayak complex between 1948 and 1972 were ascertained from death certificates and autopsy reports with follow-up through December 1997. Excess relative risk models were used to estimate solid cancer and leukemia risks associated with external gamma-radiation dose with adjustment for effects of plutonium exposures. Both solid cancer and leukemia death rates increased significantly with increasing gamma-ray dose (P < 0.001). Under a linear dose-response model, the excess relative risk for lung, liver and skeletal cancers as a group (668 deaths) adjusted for plutonium exposure is 0.30 per gray (P < 0.001) and 0.08 per gray (P < 0.001) for all other solid cancers (1062 deaths). The solid cancer dose-response functions appear to be nonlinear, with the excess risk estimates at doses of less than 3 Gy being about twice those predicted by the linear model. Plutonium exposure was associated with increased risks both for lung, liver and skeletal cancers (the sites of primary plutonium deposition) and for other solid cancers as a group. A significant dose response, with no indication of plutonium exposure effects, was found for leukemia. Excess risks for leukemia exhibited a significant dependence on the time since the dose was received. For doses received within 3 to 5 years of death the excess relative risk per gray was estimated to be about 7 (P < 0.001), but this risk was only 0.45 (P = 0.02) for doses received 5 to 45 years prior to death. External gamma-ray exposures significantly increased risks of both solid cancers and leukemia in this large cohort of men and women with occupational radiation exposures. Risks at doses of less than 1 Gy may be slightly lower than those seen for doses arising from acute exposures in the atomic bomb survivors. As dose estimates for the Mayak workers are improved, it should be possible to obtain more precise estimates of solid cancer and leukemia risks from protracted external radiation exposure in this cohort.

Adult↗
PubMed2000

Lung cancer mortality among male nuclear workers of the Mayak facilities in the former Soviet Union.

An analysis of lung cancer mortality in a cohort of 1,669 Mayak workers who started their employment in the plutonium and reprocessing plants between 1948 and 1958 has been carried out in terms of a relative risk model. Particular emphasis has been given to a discrimination of the effects of external gamma-ray exposure and internal alpha-particle exposure due to incorporated plutonium. This study has also used the information from a cohort of 2,172 Mayak reactor workers who were exposed only to external gamma rays. The baseline lung cancer mortality rate has not been taken from national statistics but has been derived from the cohort itself. For both alpha particles and gamma rays, the results of the analysis are consistent with linear dose dependences. The estimated excess relative risk per unit organ dose equivalent in the lung due to the plutonium alpha particles at age 60 equals, according to the present study, 0.6/Sv, with a radiation weighting factor of 20 for alpha particles. The 95% confidence range is 0.39/Sv to 1.0/Sv. For the gamma-ray component, the present analysis suggests an excess relative risk for lung cancer mortality at age 60 of 0.20/Sv, with, however, a large 95% confidence range of-0.04/Sv to 0.69/Sv.

Alpha Particles↗
PubMed2000

Bone cancers in Mayak workers.

Bone cancer mortality risks were evaluated in 11,000 workers who started working at the "Mayak" Production Association in 1948-1958 and who were exposed to both internally deposited plutonium and external gamma radiation. Comparisons with Russian and U.S. general population rates indicate excess mortality, especially among females, plutonium plant workers, and workers with external doses exceeding 1 Sv. Comparisons within the Mayak worker cohort, which evaluate the role of plutonium body burden with adjustment for cumulative external dose, indicate excess mortality among workers with burdens estimated to exceed 7.4 kBq (relative risk = 7.9; 95% CI = 1.6-32) and among workers in the plutonium plant who did not have routine plutonium monitoring data based on urine measurements (relative risk = 4.1; 95% CI = 1.2-14). In addition, analyses treating the estimated plutonium body burden as a continuous variable indicate increasing risk with increasing burden (P < 0.001). Because of limitations in current plutonium dosimetry, no attempt was made to quantify bone cancer risks from plutonium in terms of organ dose, and risk from external dose could not be reliably evaluated.

Adult↗
PubMed2000

Liver cancers in Mayak workers.

Liver cancer mortality risks were evaluated in 11,000 workers who started working at the "Mayak" Production Association in 1948-1958 and who were exposed to both internally deposited plutonium and external gamma radiation. Comparisons with Russian liver cancer incidence rates indicate excess risk, especially among those with detectable plutonium body burdens and among female workers in the plutonium plant. Comparisons within the Mayak worker cohort which evaluate the role of plutonium body burden with adjustment for cumulative external dose indicate excess risk among workers with burdens estimated to exceed 7.4 kBq (relative risk = 17; 95% CI = 8. 0-36) and among workers in the plutonium plant who did not have routine plutonium monitoring data based on urine measurements (relative risk = 2.8; 95% CI = 1.3-6.2). In addition, analyses treating the estimated plutonium body burden as a continuous variable indicate increasing risk with increasing burden (P < 0.001). Relative risks tended to be higher for females than for males, probably because of the lower baseline risk and the higher levels of plutonium measured in females. Because of limitations in current plutonium dosimetry, no attempt was made to quantify liver cancer risks from plutonium in terms of organ dose, and risk from external dose could not be reliably evaluated.

Body Burden↗
PubMed1999

Characteristics of the cohort of workers at the Mayak nuclear complex.

At Branch No. 1 of the Russian State Research Center "Biophysics Institute", a registry has been created of workers at the "Mayak" Production Association, the first nuclear complex in Russia. This registry includes 18,830 persons hired at Mayak's nuclear reactors and radiochemical and plutonium production plant between 1948 and 1972. Twenty-five percent of these workers are women. As of December 31, 1994, the vital status is known for approximately 90% of the cohort members. A total of 5,118 persons have died. The cause for 97% of total deaths has been ascertained. The cohort members were exposed to both external gamma radiation and internal radiation from incorporated plutonium. The plutonium body burden has been measured in 30% of the cohort members with potential for plutonium exposure. External gamma-ray doses were in the range from tenths of milligrays to about 10 Gy, and plutonium body burdens were up to about 260 kBq. In view of the nature of the Mayak worker cohort, it has the potential to provide reasonably precise, quantitative estimates of the long-term health effects associated with chronic low-dose-rate exposure to external gamma radiation as well as internal radiation from plutonium. However, a number of issues must be addressed before credible risk estimates can be obtained from this cohort. These issues include the development of an appropriate internal comparison group and/or external rates and separating of the effects of internal and external exposures on risk estimates.

Cause of Death↗
PubMed1998

Lung cancer risk due to exposure to incorporated plutonium.

An epidemiological study has been carried out among 1,479 male workers who started working at the "Mayak" Production Association in 1948-1958 and were exposed to external gamma radiation and plutonium aerosols. Lung cancer mortality for the follow-up period 1948-1993 has been analyzed. No statistically significant association of lung cancer mortality and external gamma-ray dose has been revealed in the range of accumulated doses of 0.2-5.5 Gy. Association of lung cancer mortality and the dose of alpha-particle radiation to the lung is statistically significant. In the dose range below 30 Sv, this association can be described in terms of a linear nonthreshold function. Lifetime lung cancer risk in the dose range below 30 Sv is 1.21 x 10(-2)Sv(-1).

Adult↗
PubMed1996

Mortality among workers with chronic radiation sickness.

This study is based on a registry containing medical and dosimetric data of the employees who began working at different plants of the Mayak nuclear complex between 1948 and 1958 who developed chronic radiation sickness. Mayak is the first nuclear weapons plutonium production enterprise built in Russia and includes nuclear reactors, a radiochemical plant for plutonium separation, and a plutonium production plant. Workers whose employment began between 1948 and 1958 exhibited a 6-28% incidence of chronic radiation sickness at the different facilities. There were no cases of chronic radiation sickness among those who began working after 1958. Data on doses of external whole-body gamma-irradiation and mortality in workers with chronic radiation sickness are presented.

Chronic Disease↗
PubMed1994

Mortality from malignancies of the hematopoietic and lymphatic tissues among personnel of the first nuclear plant in the USSR.

This paper reports results from the study of mortality from malignancies of the hematopoietic and lymphatic system among personnel of the first nuclear reactor and processing plant in the USSR. Two registers have been set up. They include all personnel of the atomic reactor (register A) and of the radiochemical processing plant (register B). The operation of these installations started in 1948, and two cohorts were formed; cohort I includes those who started employment between 1948 and 1953, cohort II those who started employment from 1954 to 1958. The predominant contribution to the occupational exposure was from external gamma-radiation. Adverse radiation situations prevailed during the first years at both facilities, and this resulted in substantial exposures of the personnel. Significant increases of the total cancer mortality rates and the proportion of malignancies of the haematopoietic and the lymphatic system were seen in the internal comparison only in cohort I of male workers from facility B. In the same cohort there was a statistically significant excess of the standardized mortality rates from malignancies of the haematopoietic and the lymphatic system over the population rates in the Soviet Union. Our estimate for the excess relative leukemia risk is 1.45/Gy, which is 2.7 times less than the relative excess risk of 3.92/Gy that was observed for the A-bomb survivors over age 20 ATB (Shimizu et al. 1987).

Cohort Studies↗
PubMed1994

Mortality from cardiovascular diseases among male workers at the radiochemical plant of the 'Mayak' complex.

An epidemiologic retrospective study was conducted on the basis of a personnel registry, including 9373 male workers who had started to work at the radiochemical plant during the period from 1948 to 1972, inclusive. Male mortality from cardiovascular disease proved to be 271.1 cases in 100,000 persons/year on average. The age-standardized mortality amounted to 502.5 cases in 100,000 persons/year, which is significantly lower than that of the entire male population. Regarding the structure of mortality from cardiovascular diseases in the studied male groups, the mortality rate from ischemic heart disease (IHD) was 63.7% and that from cerebrovascular disease 21.5%, compared with 57% and 30%, respectively, for the general male population. Mortality from cardiovascular diseases is lower in the study groups than in the general public and does not depend on the external gamma-irradiation dose.

Adult↗
PubMed1994

Mortality from external causes among the personnel of Mayak's radiochemical plant.

The mortality rate from accidents, poisoning, and traumas was analyzed in 12,806 persons who started work at the radiochemical plant from 1948 to 1972. 559 persons died from these causes, which corresponds to 21.1% of the total number of deaths. The global and age-specific mortality rates appeared to be lower than those for the general population. The structure of mortality from external causes differed in some way from that of the general population: the percentage of accidents connected with transport and of murders was lower, whereas it was higher for suicides. The mortality rate from specific causes including suicides, however, was lower than in the general population. The level of radiation exposure did not influence the mortality rates from the studied causes.

Accidents, Traffic↗
PubMed1991

[Malignant neoformations of the hematopoietic and lymphoid tissues in the personnel of the 1st plant of atomic industry].

Rates of mortality from hemopoietic and lymphoid malignancies for 1948-1987 were studied in male staff of industrial atomic reactors and radiochemical industry for irradiated uranium processing versus dose of external gamma radiation. An increase in mortality due to radiation--induced acute leukemia was registered in the radiochemical industry staff 5-10 years following the start of exposure and was associated with high dose of external radiation. The risk of acute leukemia for this period was 1.65 x 10(-3) x Sv-1 cases during 5 years whereas within the other 30-35 years of follow-up the risk of death from hemolymphoblastosis or acute leukemia was less than 1 x 10(-3) x Sv(-1) during 5 years.

Hodgkin Disease↗
PubMed1991

[The irradiation of the personnel of industrial and power-generating atomic reactors].

The authors represent the time course of irradiation of the personnel of uran-graphite reactors in the period of starting up the first one in 1947 up to 1988 and atomic power stations of various types over the period of 1978-1987. Irradiation of the personnel of industrial reactors was continually on the decrease. While in 1949 over 99% of the personnel were exposed to a dose exceeding the then maximum permissible dose of 15 cSv, in 1957 the average annual dose of external radiation was decreased to 5 cSv. Beginning from 1974 cases of irradiation of the personnel over the existing MPD in normal operation of reactors were practically ruled out. The improvement of working conditions at nuclear power stations provided rather low exposure doses for the personnel (an average of 0.2-0.8 cSv annually).

Aerosols↗
PubMed1990

[The medical sequelae of the radiation accident in the Southern Urals in 1957].

As a result of an accidental outburst of long-lived radionuclides at the nearest zone of the trace, a dose rate of gamma-radiation was several dozen CGy/h and in the open country at some populated areas it was 0.1 CGy/h. The evacuation of 10730 persons permitted a decrease of possible radiation doses 2-24-fold. A follow-up of persons who had been exposed to the highest effective equivalent doses of radiation before the evacuation revealed unstable indices of leukocytes and platelets (however they were within normal variations) in the first 2 years. Morbidity and mortality rates among the adults, the rates of congenital diseases and pediatric mortality did not differ from the control values. The rate of families having children born from persons aged 10 to 30 at the time of the accident did not differ from the similar rates for the USSR; this rate was lower by 5-10% than the control values for persons aged 0 to 9 at that time. Standardized birth rates in the study group (31 x 8,10(-3)) were much higher than in the control group (18 x 4,10(-3)).

Accidents↗