[On the problem of permissible levels of emergency and subsequent occupational radiation exposure for people of reproductive age].

The results of studies of indices of reproductive function in 3 groups of males examined accordingly to an unified method: Group 1 - The staff of the Kalinin Nuclear Power Plant (KNPP) and the Smolensk Nuclear Power Plant (SNPP), who worked for liquidation of consequences of the accident (LCA) in 1986-87 at the Chernobyl Nuclear Power Plant (ChNPP), group 2 - the staff of the KNPP and the SNPP who did not work for LCA in ChNPP and the group 3 - the liquidators of the accident at ChNPP who were not included in the staff but are registered in the register of LPA participants in the Ryazan region are presented. The occurrence of congenital malformations (CM) and intrauterine growth retardation (IUGR) in infants, indices of unfavourable outcomes of pregnancy (UOP) in the families of males, describing the possible radiation-induced genetic effects in male germ cells was evaluated It was made a conclusion that the given in NRB-99/2009 constraints for emergency and subsequent occupational radiation exposures of males fail to provide protection from genetic effects in the offspring. The necessity to increase the duration of the protected reproductive period in males, on which there are extended restrictions for occupational and emergency radiation exposures from 30 years of age, as it is now accepted to the age of 35 years is demonstrated.

[Occupational exposure and the reproductive health of man--personnel of the producing department of Smolensk NPP].

A study of the reproductive health of man--personnel of the producing department of Smolensk NPP did not determine the influence of occupational exposure on the indices of child-bearing and on the prevalence of the sterility of men. At the same time focuses attention the fact of the generation of children in more than 30% men of older than 30 years, at the age, to which are not extended the additional requirements of the limitation of irradiation, or the fact of child-bearing in man--personnel with the accumulated doses more than 100 mSv, with which increases the risk of genetic effects in descendants.

[Autoimmune processes after long-term low-level exposure to electromagnetic fields (the results of an experiment). Part 1. Mobile communications and changes in electromagnetic conditions for the population. Needs for additional substantiation of the existing hygienic standards].

Mobile communications provides a new source of electromagnetic exposure for almost the whole population of the Russian Federation. For the first time in the history of civilization the brain of mobile phone users was exposed to localized radiofrequency (RF) electromagnetic fields (EMF). Population exposure from the base stations is also considered to be specific. However, existing standards for limiting the exposure do not account for this special EMF source and may not ensure the absence of health effects. There was a need for reliable information that would extend databases used for development of new standards. As recommended by the World Health Organization an additional experiment was performed under the supervision of foreign experts, which showed changes in autoimmune status in rats after long-term low-level RF EMF exposure with an incident power density of 500 microW/cm2.

[Autoimmune processes after long-term low-level exposure to electromagnetic fields (the results of an experiment). Part 5. Impact of the blood serum from rats exposed to low-level electromagnetic fields on pregnancy, foetus and offspring development of intact female rats].

This study evaluated possible adverse effects of injection of blood serum from rats exposed to microwaves at a power density of 500 microW/cm2 on pregnancy and foetal and offspring development in intact female rats. The study was performed with 59 pregnant Wistar rats. In utero mortality, embryo and foetal body weights and placenta weight were used for the evaluation of embryo and foetal development. Generally accepted integral and specific parameters were used for the evaluation of postnatal development of offspring during the first 30 days of life. It was shown that intra peritoneal injection of blood serum from IMF exposed rats (chronic 30-day RF exposure at 500 microW/cm2) to intact rats on the 10th day of pregnancy resulted in adverse effects on foetal and offspring development. Total mortality (in utero + postnatal) as well as delay in offspring development was higher in this group.

[Congenital malformations among offspring of the liquidators of the consequences from Chernobyl accident].

The frequency and the structure of congenital malformations at children of the liquidators of the consequences from Chernobyl accident, undergone to an external scale gamma-irradiation in dozes up to 25 cGy. In total is surveyed 2379 newborn at which is revealed 318 intrauterine development defects. The received results are compared to the earlier published data on birth of congenital malformations in families of the fathers who have undergone to an irradiation in connection with professional activity at the enterprises of a nuclear industry, with emergency irradiation, with irradiation as a result of explosions of nuclear bombs in Japan, and are discussed from positions of the basic rules (situations) of radiating genetics. Total frequency, the frequency of forms 21 of inherent defects of development, taken into account in the International register of congenital malformations and frequency 9 forms heaviest of congenital intrauterine development defects with the high contribution mutation components at children of the liquidators authentically is higher than on the average on Russian Federation. The dependence of the frequency congenital malformations at children from dozes of an irradiation of the fathers--liquidators is revealed. The curve of dependence of the frequency of congenital malformations from time, past after work up to copulation carries arched character with peak of rise of frequency of congenital malformations in 2-3 years and decrease in 6-7 years.

[Genetic effects in the liquidators of consequences of Chernobyl Nuclear Power Plant accident].

The purpose of the present research was the estimation of probable genetic consequences at the liquidators of the consequences of Chernobyl accident in 1986-1987. The research is made on two groups of the liquidators. The first group included the liquidators taking place on the account in the branch register and working now at the enterprises of a nuclear industry. The second group included 902 liquidators of consequences of Chernobyl accident in 1986 constantly living in the Ryazan area and which are taking place on permanent observation the account in regional hospital. For an estimation of probable genetic effects analyzed the data on frequency and outcomes pregnancy of the wives of the liquidators, on condition and on diseases of newborn, on switching intrauterine development defects (IDD). The analysis carried out depending on dozes of an irradiation: up to 5 cGy; 5-10 cGy and 10-25 cGy. Received materials testify, that at the liquidators, at a doze of an external irradiation 10-25 cGy, the determined effects--period long sterility, kept at a part them till 3 years come to light. The set of the received data, such as depending from the dose increase of frequency of spontaneous abortions and of inherent defects of development of newborn, the increase of frequency diseases of newborn and share newborn with low weight, allows to make a conclusion about an induction of genetic effects in sexual cells of the liquidators of consequences of Chernobyl accident at dozes of an external irradiation more than 10 cGy. Taking into account high biological efficiency of alpha-radiation (K = 20), and of beta-radiation (K = 2-4), the equivalent effective doze male gonads (testes) in 3-5 times is higher, than estimated only from external gamma-radiation.

[Combined effects of radiation and iodine deficiency on pregnancy and fetus].

The Chernobyl accident had combined effects of radiation and iodine deficiency (ID) on pregnancy. The establishment of a role of each of these factors in the genesis of comorbidity is of fundamental importance in the assessment of a radiation risk and in the development of goal-oriented preventive measures for reproductive health and antenatal development of an infant. The problem of impact of ID on fetal radiation damages is mainly that on radiation damages to the thyroid. The solution of this problem assumes particular topicality if radiation damages are due to the incorporation of radioactive iodine. The findings are indicative of the summation of thyroid abnormalities characteristic for each influencing factor. There is a more pronounced biological effect of radioactive iodine in the thyroid in ID.

[Modifying influence of iodine deficiency on radiation damage to the fetus (review)]. / Modifitsiruiushchee vliianie iodnogo defitsita na radiatsionnye porazheniia ploda (obzor).

It known an oppressing action of radiation, including radioactive iodine isotopes on the reproductive system and fetus development. There are clinical data on a negative influence of iodine deficiency on the course of pregnancy and fetus development resulting from hormonal disfunction of thyroid gland and a mother-fetus system. There are no data about a character and mechanisms of interaction of radiation and iodine endemia at the combined action on the gonads and fetus. The urgency of this problem is caused by the fact that many regions of the country are characterized to some extent by iodine deficiency in local food and water (in Russian Federation such regions make approximately 50% of territories), and the opportunity of radiation accidents at nuclear plants with contamination of the environment with products of nuclear division (significant part of which is radioactive iodine isotopes is an objective reality. The analysis of a few published and own experimental data allows us to conclude that the combined influence of an external gamma-irradiation and iodine deficiency on reproductive function has a synergic character.

[Teratogenic effects of incorporated radionuclides]. / Teratogennye éffekty inkorporirovannykh radionuklidov.

Experimental data on teratogenic effects induced by incorporated alpha, beta and gamma-emitters were analyzed. It was found that the radioactive substances as well as external irradiation induced teratogenic effects. Teratogenesis caused by incorporated radionuclides has some peculiarities compared to the effect caused by fetus exposure to external radiation. These peculiarities are related to the fact of the limited penetration of incorporated radionuclides via placenta barrier so the radiation fetal doses are accumulated within long period of time and radiation dose rates are relatively low. The exposure to incorporated radionuclides does not induce severe developmental defects. Most frequent developmental defects of fetus include its death, general retardation of the development and growth. In such case the earlier pregnancy term was affected by radionuclide the more severe fetal damages occur in fetus because of the gradual increase of absorbed dose even in case of single intake of radionuclide. RBEs of radionuclides if compared to that for external gamma radiation are evaluated as follows: 2-4 (tritium oxide), 20 (241Am), 50 (238Pu) and 3-5 (131I in thyroid).

[Frequency of dominant lethal mutations induced by combined exposure to incorporated 137Cs and external gamma-irradiation in mice]. / Chastota dominantnykh letal'nykh mutatsii, indutsirovannykh sochetannym deistviem inkorporirovannogo 137Cs i vneshnego gamma-izlucheniia, u myshei.

The genetic effect of combined exposure to incorporated 137Cs and external gamma-irradiation was studied in germ cells of male mice. The activity of incorporated 137Cs was 3.7 x 10(4) Bq/g. The dose of external gamma-irradiation was 1.5 Gy. In the case of combined exposure, mice were treated with a cesium solution immediately after irradiation. The genetic effect was estimated by the frequency of dominant lethal mutations (DLM) induced at different stages of spermatogenesis. Upon combined exposure to external and internal irradiation, the frequency of DLM in premeiotic cells significantly exceeded the total frequency of DLM induced by separate exposure to external and internal irradiation; i.e., a marked synergistic interaction of external and internal irradiation was observed.

[The formation of absorbed doses of 137Cs in the body of the female and her progeny during suckling]. / Formirovanie pogloshchennykh doz ot 137Cs v organizme samki i potomstva v period molochnogo vskarmlivaniia.

The transfer of 137Cs with maternal milk to progeny was studied in rats. The rats were administered with 25 kBq/g of 137Cs nitrate (pH = 6) in a single oral dose immediately after delivery. Nonpregnant females served as control. Absorbed doses per activity unit to lactating rats were 23% lover than to nonlactating ones. Over the suckling period, absorbed doses to young rats amounted to about 35% of the absorbed dose to the nursing female. For nonlactating females, the internal dose approximately equalled the sum of doses to the nursing female and young rats.

[Kinetics of metabolism and mechanisms of formation of absorbed doses in the mouse testis from incorporated Cs-137]. / Kinetika obmena i zakonomernosti formirovaniia pogloshchennykh doz v semennikakh myshi ot inkorporirovannogo 137Cs.

The process of accumulation of absorbed doses from incorporated 137Cs in the body and gonads of male mice was investigated in our experiments. The radionuclide accumulated in gonads has very long time of excretion, and as result the radionuclide can be treated as long lasting and permanent source of alpha- and beta-radiation in gonads. The rates of total exposed doses in gonads were in 2.0-3.0 times higher then the average total exposed dose in hole body.

[Genetic effect of incorporated 137 Cs in male mice after single injection of the isotope]. / Geneticheskii éffect inkorporirovannogo 137 Cs u samtsov myshei pri odnokratnom vvedenii izotopa.

A comparative study of the incidence of genetic damages induced in mouse male germ cells by a single injection of 137Cs and external gamma-irradiation shows that the incidence of dominant lethal mutations in the postmeiotic cells is similar with both radiation types. The frequency of reciprocal translocations in stem cell spermatogonia was considerably lower with 137Cs than with external gamma-irradiation which might be attributed to the prolonged effect of the radionuclide.

[Genetic effect of incorporated 137 Cs on male mice after long-term administration of the isotope]. / Geneticheskii éffect inkorporirovannogo 137 Cs u samtsov myshei pri dlitelnom vvedenii izotopa.

A comparative study has been made of the incidence of genetic damages to male mouse germ cells induced by chronic action of incorporated 137Cs and external gamma-radiation. It has been shown that the genetic efficiency was nearly the same with both radiation types under conditions of equal, with respect to time and value, absorbed dose formation in gonads.

[The use of ferrocyanides for obtaining pure meat production in contaminated areas following the accident at the Chernobyl Atomic Electric Power Station]. / Primeneneie ferrotsianidov dlia polucheniia chistoi miasnoi produktsii na zagriaznennykh territoriakh posle avarii na Chernobyl'skoi AES.

The paper reports a new technique of obtaining radioactive Cs-free meat in the regions contaminated with radionuclides as a result of Chernobyl accident. The method is based on specific digestion features of ruminant animals. Ferriferrocyanide compounds are proposed as sorbents. Ferrocene is most efficient when introduced into mixed feed (1-3 g/day for sheep, 3-5 g/day for calves and young bulls) once a day. After that the animals can be fed radioactively contaminated forage and graze on contaminated land.

[The effect of one-time external gamma irradiation at different stages of ontogeny on the thyroid status of rats]. / Vliianie odnokratnogo vneshnego gamma-oblucheniia na raznykh étapakh ontogeneza na tireoidnyi status krys.

A single external gamma-irradiation (1 Gy) of rats on day 35 of their life causes stable structural and functional disturbances in the thyroid gland leading to the development of hypothyrosis at the remote times following irradiation which is demonstrated by the decrease in the concentration of thyroxine in the blood, increase in the thyrotropic function of the hypophysis and inhibition of the activity of tyrosine-dependent enzyme, alpha-glycerophosphate dehydrogenase, in the liver. Disturbances induced by such exposure in the thyroid gland of adult rats are insignificant and compensatory in time.

[Role of the liver in optimization of the thyroid status of rats in hypothyrosis caused by irradiation]. / Uchastie pecheni v optimizatsii tireodnogo statusa u krys pri gipotireoze, vyzvannom oblucheniem.

Experiments were made on 100 random bred rats of various age groups, controls and animals exposed to single external gamma-radiation at a dose of 1 Gy on the 35th day of life. Thyroxine and triiodothyronine concentrations were investigated in peripheral blood and separately in arterial blood, in thyroid, portal and hepatic venous blood. The activity of T4 conversion into T3 by 5'-deiodinating enzymes of the liver microsomal fractions and the activity of the liver mitochondrial enzymes--cytochrome of C-oxidase and alpha-glycerophosphate dehydrogenase were also investigated. A decrease in thyroid excretion of T4 and T3 and T4 blood concentration was noted in rats exposed to irradiation. 5'-thyroxine deiodinating activity of the microsomal enzymes was elevated in the liver of such rats; a T3 ratio in the blood outflowing from the liver was on the increase. A conclusion has been made that 5'-deiodination in the liver of rats with postradiation hypothyrosis is effected as a result of increased production of the most active hormone T3 from less active T4.

[Response of the developing thyroid gland of rats to a single gamma-irradiation in the period of intrauterine development]. / Issledovanie reaktsii razvivaiushcheisia shchitovidnoi zhelezy krys na odnokratnoe vneshnee gamma-obluchenie v period vnutriutrobnogo razvitiia.

A single external exposure of pregnant rats to 2 Gy gamma-radiation caused changes in the functional status of the thyroid gland in offsprings at varying times of the postnatal development. The disturbance of the thyroid hormones balance in the blood, destruction of the thyroid gland combined with high functional tension of secretory elements, and activation of the thyrotropic function of hypophysis were revealed at remote times after irradiation.

[The biological action of radioactive carbon. The metabolic kinetics and biological effects of the combined action of radioactive carbon (14C-glucose) and sodium nitrite chronically administered]. / Biologicheskoe deistvie radioaktivnogo ugleroda. Kinetika obmena i biologicheskie éffekty sochetannogo deistviia radioaktivnogo ugleroda (14C-gliukozy) i nitrita natriia pri khronicheskom vvedenii.

A study was made of the effect of sodium nitrate (3.1 and 0.3 g/l) on the metabolism kinetics and the biological effects of 14C-glucose (13 kBq/rat/day) that were chronically administered to rats. After both separate and combined administration of the radiation and chemical agents, no substantial changes were detected in the kinetics of metabolism and biological effect of 14C. Six months after the onset of the experiment, the reproductive function of the experimental rats was impaired.

[Evaluation of genetic consequences of 238Pu incorporation into mammals]. / Otsenka geneticheskikh posledstvii postupleniia 238Pu v organizm mlekopitaiushchikh.

The genetic effects of gonadal burdens of 238Pu after single injection were studied in male mice. The activity of plutonium was 7 to 1850 Bk/g. The average doses of accumulated alpha-particles in testis varied from 2 to 96 Gy.10(-2), the dose rate being 0.004 to 1 Gy.10(-2) per day. The genetic end points are: the dominant lethal mutation rate; the frequency of reciprocal translocations; the recessive lethal mutation rate and frequency of abnormal sperm head morphology. For all tests used, no linear dependence of the effect on the alpha-dose was observed. The RBE value of alpha-irradiation was 10-20 relative to chronic gamma-irradiation.