The Chernobyl nuclear power plant accident happened on April 26, 1986. We investigated the cause of the striking increase in frequency of thyroid cancer in children who lived within a 150 km radius of Chernobyl and who were born before and after the accident. No thyroid cancer was seen in 9472 children born in 1987-89, whereas one and 31 thyroid cancers were recorded in 2409 children born April 27, 1986, to Dec 31, 1986, and 9720 born Jan 1, 1983, to April 26, 1986, respectively. Short-lived radioactive fallout caused by the Chernobyl accident probably induced thyroid cancer in children living near Chernobyl.
Health effects as a result of the accident at the Chernobyl nuclear power plant occurred in 1986 are considered in the paper. Wrong prognosis of the health effects with respect to mortality and morbidity among the population exposed to low radiation doses is shown. Proven increase in thyroid cancer cases among people who were children aged from 0 to 18 at the time of the accident is shown. Linear relationship between thyroid cancer cases and dose to thyroid ranged from 0.2 to 4.0 Gy is considered. An additional absolute risk of thyroid cancer in children varies in the range 1.9-2.6 cases per 10(4) person-year Gy. During the fifteen years following the accident no cases of acute and chronic radiation sickness have been revealed because the population living in contaminated areas received low radiation doses. Also, exposures to low radiation doses did not result in excess of malignant tumors among population. In some cases the outcomes of acute radiation sickness were as follows: radiation damages to the skin, cancer cataracts, development of oncopathology.
Heterotrimeric G proteins participate in the signal transduction cascade. Adult thyroid tumors have been shown to harbor specific point mutations in codons 201 and 227 of the G(s)alpha subunit of the adenylate cyclase stimulator. This protein affects the GDP/GTP turnover and finally results in an enhanced activation of G(s) and thus adenylate cyclase. We attempted to find out if G(s)alpha gene mutations were present in thyroid tumors of children from Belarus after the Chernobyl nuclear accident. Paraffin sections of 20 thyroid tumors were used for PCR amplification by oligonucleotide intron primers flanking exons 8 and 9, encompassing codon 201 and 227, respectively. By direct sequencing of the 274-bp amplification product, we did not detect any mutations of the G(s)alpha gene in codon 201 or 227. In contrast to thyroid neoplasia of adults, G(s)alpha gene mutations do not play a role in the development of childhood thyroid tumors after the Chernobyl reactor accident.
[Activities of the Byelorussian scientific association of phthisiatrists and the phthisiatric organization of the Republic in the circumstances of complicated critical state of tuberculosis in connection with the Chernobyl AES accident]
Presents the data of analysis of medical files of therapeutic institutions, of questionnaires distributed among dentists, and the results of examinations of 883 children aged 3 to 6, living in 19 towns of Byelorussia. The incidence and clinical picture of a number of dental diseases were found changed in the children living in the regions contaminated with radionuclides, as well as the general well-being of these children.
Great Lakes Centers for Occupational and Environmental Safety and Health, School of Public Health (M/C 922), University of Illinois at Chicago, 2121 W. Taylor Street, Chicago, IL 60612, USA. firstname.lastname@example.org
Int J Occup Environ Health. 2006 Oct-Dec;12(4):415-22
The 1986 Chernobyl accident contaminated 23% of Belarus with radioactive iodine and long half-life radionuclides. Radiation causes breast cancer. Population-based breast cancer incidence data from the Belarus National Cancer Registry were used to study secular trends and urban-rural differences, and determine whether an effect of Chernobyl radiation exposure was discernable. Trends in age-standardized incidences in Gomel and Vitebsk oblasts maximally and minimally exposed to Chernobyl radiation, respectively, were compared for 1978-2003 among all women, and women aged 30-49, separately for urban and rural areas. Incidences were higher and increasing more rapidly in urban than rural areas of both oblasts, annually increasing 0.150 +/- 0.008 vs. 0.098 +/- 0.007 new cases per 10,000 persons, p
A descriptive analysis of birth defects and malformations was performed to assess whether the rates of these defects correlate with the geographic areas of Belarus that received different levels of 137Cs contamination resulting from the Chernobyl catastrophe. Since this accident in 1986, the frequency of both congenital and fetal abnormalities in the Republic of Belarus has apparently increased. This increase is most prominent in areas with at least 555 9Bq/m2 radioactive contamination, although it has not been possible to correlate the individual dose received by a pregnant woman with the incidence of congenital malformations. The types of anomalies that were most increased in frequency were multiple congenital malformations, polydactyly, and reduction limb defects. These malformations are commonly associated with dominant new mutations. Chromosomal disorders such as occur in Down syndrome were not increased in frequency, nor could teratogenic effects be attributed to exposure to ionizing radiation. Preventive measures have apparently reduced the number of births with congenital abnormalities but have had no apparent effect on the frequency of fetal defects. Results of our analysis are consistent with the hypothesis that ionizing radiation released during the Chernobyl accident may have placed fetuses and neonates at risk for congenital malformations. Epidemiological studies are now required to determine whether a mother's radiation dose correlates with congenital malformations in her children.