[Effect of hypokinesia on the resistance of animals to the action of chemical substances]. / Vliianie gipokinezii na resistentnost' zhivotnykh k deistviiu khimicheskikh veshchestv.

Resistance of rats exposed to 20-day hypokinesia to high concentrations of vapors of ethylacetate, dioxan, and liquid fluorochlorocarbon was studied. As compared with controls, lethality of the hypokinetic animals increased upon ethylacetate and dioxan breathing and decreased upon intoxication with liquid fluorochlorocarbon. The hypokinetic animals showed decreased resistance to chronic effects of ethylacetate and perfluorated ester vapors (at a concentration of 10 and 100 mg/m3 for 90 and 30 days, respectively). This was suggested by functional and pathomorphological studies.

[Pathomorphologic changes in the organs of rats following chronic inhalation exposure to liquid polyethylsiloxane]. / Patomorfologicheskie izmeneniia v organakh krys pri khronicheskom ingaliatsionnom vozdeistvii poliétilsiloksanovoi zhidkosti

A chronic 90-day inhalation of polyethylsiloxane fluid at a concentration of 10 and 2 mg/m3 produced local irritation and general toxic effect on rats. Local irritation induced catarrhal-desqueamative tracheitis that was accompanied by a microfocal interstitial process in the lungs. The general toxic effect gave rise to interstitial myocarditis that was followed by focal cardiosclerosis and dystrophic lesions of vascular walls and areas of liver parenchyma. Changes in the thymus-lymph system and adrenal structure suggested prolonged protective tension of the animal body. A chronic 90-day inhalation of polyethylsiloxane at a concentration of 0.2 mg/m3 brought about no pathological lesions in the microstructure of animal organs.

[Toxicological evaluation of ethyl acetate in conditions of sealed cabin atmospheres]. / Toksikologicheskaia otsenka étilatsetata v usloviiakh atmosfery germeticheskikh kabin

Ethyl acetate was studied as an atmosphere contaminant in an enclosed environment. A 90-day continuous experiment on 160 white rats and 120 white mice with three concentrations of the compound (43, 10 and 2 mg/m3) was carried out. Ethyl acetate used in the first two concentrations caused functional disturbances in the state of animals and morphological changes in their viscera. Ethyl acetate at a concentration of 2 mg/m3 was ineffective. The data obtained allow recommendations of permissible concentrations of ethyl acetate vapours in an enclosed atmosphere in relation to a different time of man's exposure.

[Effect of hypokinesia and lowered barometric pressure on the tolerance of animals to the action of ethyl acetate]. / Vliianie gipokinezii i ponizhennogo barometricheskogo davleniia na ustoichivost' zhivotnykh k deistviiu étilatsetata

Experiments were carried out to study the resistance of rats to an acute effect of ethylacetate vapors at concentrations of 25 to 69 g/m-3 after their 20-day exposure to hypokinesia and 20-day exposure to altitudes of 3200 and 5000 m. The effect of ethylacetate at concentrations of 47 and 10 mg/m-3 on the rats in a chronic 90-day experiments was also investigated. After an exposure to hypokinesia and hypoxia the sensitivity of the rats to an acute effect of ethylacetate vapors increased 2- or 3-fold. The chronic inhalation of the substance by the hypokinetic animals brought about disorders in the brain microstructure and renal pathology. The poisoned animals that retained normal motor activity displayed serious pathological changes in the thyroid gland. It is concluded that changes in the reactivity of the animal and human body to chemical agents must be taken into consideration when developing standards for the space cabin atmosphere.