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The use of ultrasonic irradiation in the reactions of trialkyl borates with octahydroxytetraoctyl[l 4] metacyclophane allowed us obtaining tetraalkoxyboratocavitands with higher yields and under milder conditions. We first obtained 1,3,2-dioxaborolane and 1,3,2-dioxaborinane derivatives of tetraoctyl[l 4]metacyclophane using ultrasonic irradiation. Boratocavitands were converted into the corresponding amine complexes with isobutylamine.

Analysis of experimental data about the quantitative and qualitative chemical make-up of air in the orbital station Mir and International space station (ISS) showed a permanent presence of silicon. The main source of silicon contaminants seems to be a variety of polymethyl siloxane liquids and siloxane coating of electronics. The article describes the volatile silicon contaminants detected in space stations air. To control concentrations of silicon, the existing air purification system needs to be augmented with carbons having the micropore entrance larger than diameters of silicon-containing molecules. It is also important to elaborate the technology of polymethyl siloxane liquids synthesis so as to reduce the amount of volatile admixtures emission and to observe rigorously the pre-flight off-gassing requirements with special concern about silicon coatings.

The paper deals with the ability of human olfaction to identify odours associated with thermal destruction of polymers. The investigations confirmed the ability of early detection of equipment overheating and subjective odour evaluation using the 5-point intensity scale and calculating the relation of odour intensity to the maximum admissible concentration of volatile chemical contaminants aboard piloted space vehicles. Emission of gases by polymers in electrical equipment starts with heating temperature rise to 100 degrees C. A new odour smelled by only some of humans due to individual perception signifies typically that emitted gases are below MAC for space vehicle. Odour sensed by everyone though not irritating signifies, as a rule, of chemical contamination above MAC but not contingency. Symptoms of irritation by products of thermal destruction of polymers signify contingency and require the use of personal protection equipment.

Chronic combined exposure to low concentrations of chemical substances (equal to the maximal admissible limits for space vehicles) is fraught with an increase in chromosomal aberrations in bone marrow cells as compared with the spontaneous chromosome aberration rate. In addition to the cytogenetic evidence, there were also statistical phase shifts in metabolic parameters of erythrocytes (enzymes involved in the basal metabolism and a number of metabolites), leukocyte count in peripheral blood, and the total quantity of karyocytes in the bone marrow. No significant changes were found in organs of the immune and reproductive systems.

Wistar rats were used to study inhalation toxicity of octafluoropropane (OFP, freon-218) at the following concentration: 300 g/m3 (4-hrs), 30 g/m3 (0.5 to 4 hrs), 3 g/m3 (8 hrs), and 0.3 g/m3 (16 hrs). According to the histological analysis, OFP at the concentrations of 300 and 30 g/m3 had a politrophic toxic effect. Target organs were the lung, trachea, bronchus, heart, kidney, and the adrenaL There were dystrophic and necrobiotic lesions in the upper airways epithelium. Subacute and chronic vesicular bronchiolitis developed on days 7 and 14, respectively. Visceral organs and brain were found plethoric and the lung was found hemorrhagic. Similar lesions were seen in the trachea, bronchus, lung, liver, spleen, kidney, adrenal, heart, and the brain. Lipid redistribution was observed in the adrenal cortex and vascular reactions of renal tissue with juxtamedullar blood shunting. Toxicity of small OFP concentrations (3 and 0.3 g/m3) was distinguished by an extended aftereffect, these concentrations did not cause visible pathomorphologic changes but gave rise to an extended pathologic process detectable by biochemistry. In all concentrations, OFP impacted erythrocyte metabolism changing the lipid composition of cell membrane and activating membrane-bound adenosinetriphos-phatases. The activities of hepatocyte and myocardiac cytoplasmatic enzymes were altered in blood plasma. Increased malonic dialdehyde in blood plasma and decreased cell antioxidant GSH in erythrocytes suggested exaggerated lipid peroxidation. These data point to the necessity of revising the existing limits for OFP concentrations in air of populated areas, working areas, and closed human environments.

Based on the multiyear experience of hygienic control of the orbital stations, there are three causes of contingent air pollution: leakage of service system pipeline with chemical working bodies, spills of reagents used in biochemical and technological experiments, and air pollution by products of thermal oxidative degradation of nonmetallic materials. The authors describe their experience in successful elimination and prevention of hazardous consequences of fire aboard the space stations. Analysis of air pollution dynamics after actual fire events in the space station modules showed that it approximates a two-chamber air flow model with two phases of pollutant equilibration: first a rapid fall of concentration in the module on fire till air in the modules gets completely mixed, and then slow elimination of harmful pollutant from air. Identified were markers,--propylene and methylmetacrilate,--reacting to first signs of fire. Carbonic acid nitriles were recognized as toxic products of destruction. The positive effect of intermodular ventilation on dilution of toxic products of thermal oxidative destruction of materials was demonstrated. Satisfactory agreement of calculated and factual pollutant concentrations on board Mir permitted conclusion on applicability of the theoretical model to prediction of levels of air pollution due to contingency.

Four volunteers were enclosed for 40 days in a hypercapnic environment. Their average age was 41-59 years, body weight, 66-90 kg, and height 173-182 cm. During the study the ambient temperature was 19-23 degrees C, relative humidity, 50 +/- 20%; pO2, 19-19.5%; and pCO2, 1.3%. On test days 21-22 and 38-39 pCO2 was increased to 4% and pO2 was decreased to 17%. The time, within which pCO2 was increased to 4% on test days 38-39 when compared to test days 21-22, grew 1.5-fold and amounted to 40 hours. The subjects had three meals a day, consuming canned foodstuffs, the caloric value of which was 2982 kcal/day. In the study the following parameters were measured: malonic dialdehyde in venous blood; catalase, lactate, pyruvate, urea, acid-base content, gases in capillary blood; total nitrogen, ammonia, urea, creatinine and uric acid in 24-hour urine samples. Nitrogen balance and protein nutrition index were calculated. Results were processed using Student's t-test. During exposure lipid peroxidation increased and catalase decreased; malonic dialdehyde in blood increased, being correlated with lower hydrocarbons in exhaled air; gas and energy turnover during hypercapnic intervals enhanced. The above changes in the exhaled air composition, gas and energy turnover, biochemical blood and urine parameters remained within adaptation norm. By the second week of the recovery period the above parameters, except for nitrogen metabolism which remained slightly inhibited, returned to the normal.

Thermoregulatory reactions to sustained hypercapnia were investigated. Continuous 40-day exposure to hypercapnia (1.1-1.6% CO2 in the breathing air) in a thermoneutral area was accompanied by the development of a cooling effect that took the form of enhanced heat production beginning with exposure day 3. As the exposure to hypercapnia continued, lactate and excessive buffer bases in blood decreased, core temperature and heat content of the body declined. These changes suggest the limiting effect of hypercapnia in the above concentrations on thermogenesis, evidently at the stage of glycolytic ATP resynthesis.

Four manned experiments (4 test subjects participating in each) were carried out in a chamber of 24 m3. The effect of CO at a concentration of 10 to 45 mg/m3 on the content of carboxyhemoglobin in the blood, nonhemoglobin iron in the plasma, CO in the breathing air, catalase and peroxidase activity was studied. A correlation was found between these parameters and CO concentration in the atmosphere and exposure time. It was demonstrated that a continuous exposure (up to 90 days) to CO at a concentration of 10 mg/m3 under favorable microclimatic conditions produced no significant effect on the above mentioned biochemical paramters.

The purpose of the study was to investigate adaptive responses of the human body to chemicals of anthropogenic origin in an enclosed environment. The object of the study was ammonia, a typical metabolite and a permanent contaminant of a enclosed atmosphere. The study consisted of a prolonged and continuous exposure to ammonia at a concentration of 2.0 +/- 0.1 mg/m3 and a 24-hour exposure to ammonia at a concentration of 9.8 +/- 0.1 mg/m3. The results showed that ammonia was neutralized in a stage-by-stage manner. At first the anthropotoxin was eliminated in exhaled air. As the exposure continued, additional mechanisms became involved, i.e. ammonia binding and renal excretion. Activation of ammonia detoxication occurred without noticeable involvement of the sympathoadrenal system.

In two series of prolonged studies metabolic changes of men kept in an environment with an ammonia concentration of 2 and 5 mg/m3 were investigated. In this chronic study the following changes were seen: acetone in the exhaled air increased; glycolysis and lactate dehydrogenase enhanced; catalase decreased; changes of acid-base equilibrium manifested as metabolic acidosis of varying degree. The use of exercises of different workloads showed that those at 50% VO2max were most beneficial.