[Increasing resistance against hazardous effects of metals-containing nanoparticles as a prospective approach to health risks management].

Extremely high toxicity of metal-containing nanoparticles necessitates search of methods to increase body resistance against its harmful effects. The authors' experiments summarized in the article demonstrated that some combinations of certain biologically active substances selected according to sound theoretic background and prescribed in harmless doses can significantly decrease integral and specific manifestations of organ and system toxicity and even genotoxicity of such nanoparticles. Further development of this research direction should be recommended for practical implementation.

[Comparative experimental assessment of the impact of gold and silver nanoparticles on the phagocyting cells of the lower airways].

Judging by the cytological characteristics of the free cell population of the lower airways obtained with assistance of the bronchoalveolar lavage in 24 hours after the intratracheal instillation of equal doses of equidimensional gold or silver nanoparticles, both metals result in active recruitment of phagocytes with domination of neutrophile leukocytes, especially marked after the instillation of the nanosilver. The higher ratio of these cells count to that of alveolar macrophages gives evidence for the significantly higher cytotoxicity of the nanosilver comparing with both nanogold and even the smallest silver particles in the micrometric range. Transmission electron microscopy demonstrates similar pictures of intracellular distribution and ultra-structural damages caused by internalized nanoparticles in both types of phagocytes, while there are significant differences between cells under impact of nanosilver vs. those under impact of nanogold. The highest importance is higher propensity of the nanosilver particles to aggregation and to ingression into mitochondria with damaging these organelles.

[Comparative evaluation of alveolar phagocytosis response to intratracheally applied magnetite (Fe3O4) in nano- and micrometer ranges].

The authors compared cytotoxicity of magnetite (Fe3O4) particles in nanometric ranges (10 nm and 50 nm) and micrometer range (1 microm), analyzing changes in cellular subunits of bronchoalveolar lavage in 24 hours after intratracheal application of the particles. Findings are that the nanoparticles are more biologically aggressive than the micrometric particles, but induce more active and effective defensive reaction of alveolar fagocytosis.

[Biological prevention of combined effects of toxic metals and organic substances].

The antitoxic activity of several biological prophylactic complexes was studied in subchronic experiments on inbred albino rats exposed to a metal combination of leadchromium-arsenic-manganese-vanadium and benzo(a)pyrene, as well as phenol or naphthalene, and combinations of naphthalene-lead and phenol-naphthalene-lead. It has been shown that upon simultaneous exposure to the study combination of metals and organic poisons, it is advisable to use a biological prophylactic complex involving glutamic acid, a pectin enterosorbent, the multivitamin agent "Vitrum-Kids", calcium, vitamin C, glycine, methionine, and "Iodomarin".

[Organization of fractional monitoring of ambient air pollution by suspended matter in Russia].

The authors consider the organization of a system for monitoring of ambient air pollution by suspended matter (by fractions of less than 10 microm and less than 2.5 microm) as one of the most urgent tasks in the harmonization of the Russian and western methods for assessing the quality of the environment. The frame plan for organization of ambient air suspended matter monitoring in the countries of Eastern Europe, Caucasia, and Central Asia, proposed by the WHO European Regional Office provides basic guidelines for this system and may be adapted to Russian conditions, as evidenced by the author's experience. The paper summarizes the basic results of the studies that have established the association of respiratory disease in junior schoolchildren with exposure to PM10 and PM2.5.

[The concept of acceptable risk is the key debatable issue of the assessment and management of a risk to the population's health].

The authors hold that an open discussion on the principles of and approaches to establishing the national standards of acceptable health risks should precede the official introduction of these standards into practice in taking decisions on risk management. They criticize the sociostatistical and socioeconomic concepts of risk acceptability as both amoral and impracticable and propose an approach based on the use of the Russian standards of permissible exposure levels (maximum permissible concentrations in particular) and on the exposure-response relationships established by epidemiological studies for the computation of responses (i.e. risk levels) corresponding to the permissible exposures. In some cases that such standards of an acceptable risk are too strict in existing technological or economic practice may be introduced in a stepwise fashion, but the risks that exceed the acceptable level should be compensated for.

[Biologic prophylaxis of intoxications with inorganic compounds]. / Biologicheskaia profelaktika intoksikatsii neorganicheskimi veshchestvami.

The authors summarize theoretical principles of increasing human resistence to toxic effects of inorganic compounds polluting occupational environment and habitat, exemplify practical use of this prophylactic trend.

[Hygienic regulation of environmental air pollution with consideration of epidemiological data]. / O gigienicheskoi reglamentatsii zagriazneniia atmosfernogo vozduha s uchetom épidemiologicheskikh dannykh.

The authors hold that the maximum allowable concentrations (MAC) established in Russia for some ambient air pollutants can adversely affect human health and that they are worthy of reconsideration. This opinion is based on the published results of epidemiological studies of Western investigators and on the authors' own data obtained from the analysis by the time series method for a relationship of daily variations of dust or gaseous ambient air pollution to the so-called acute mortality or for that of the variations to respiratory symptoms and to the values of the maximum expiratory flow rate in preschool with or without respiratory abnormalities in their history; from the cross analysis of an association of the characteristics of atmospheric contamination in 13 urban areas with the prevalence of chronic respiratory diseases in junior schoolchildren, which was established by a special questionnaire. Particular emphasis should be laid on the reconsideration of not only established values, but mainly on the principles in laying down MAC for dust particles. The Western practice in measuring and evaluating risks separately for fractions of particles of varying sizes should be assessed for its use in Russian conditions; however, the authors' experience argues for this practice.

[The role of environmental and epidemiological surveys of ambient pollution in the evaluation of a risk for "acute" mortality]. / Rol' ékologo-épidemiologicheskikh issledovanii atmosfernykh zagriaznenii v otsenke riska "ostroi" smertnosti.

The paper provides evidence that there is a relationship of daily death rates to variations in the concentrations of total dust and some gaseous ambient pollutants. The great advantage of a procedure to analyze temporary variables is that it makes it possible to retrospectively use the available materials of routine monitoring of air pollution and to consider these effects (cases of death in particular). Along with the high informative value of environmental and epidemiological surveys (EES) based on the analysis of time series, this advantage allows one to recommend them for widely use within the sociohygienic monitoring system. At the same time the paper shows it necessary to control the quality of available data and to chose monitoring centers comparable in this regard. Inevitable missing data on the concentrations of different pollutants on days off and on some working days are of particular value under the actual conditions of monitoring of air pollution. The approach applied in this study to the choice of the most effective ways of filling of such gaps may be recommended. Nevertheless, incomplete data and the need for their artificial reproduction should be regarded as a source of uncertainty of specific results of EES of this type. Increments in mortality rates for a certain increase in the concentrations of pollutants may be used in the risk assessment projects when a dose-response relationship is analyzed. The larger number of EES based on the analysis of time series will be conducted in the regions of Russia, the more reliable the use of EES-grounded single risks will be at the regional and federal level.

[Dioxins: facts and conjectures]. / Dioksiny: fakty i domysly.

Dioxins and dioxin-like substances are highly toxic and extremely dangerous chemical compounds. Dioxins are formed during the thermal process associated with the use of chlorine. 2,3,7,8-tetrachlorodibenzo-1,4-dioxin is the most toxic, the most typical and well-studied agent. The most characteristic and constant indicators of intoxication with dioxin-containing substances are altered body weight, chloracne, hepatic damage, thyroid involution, structural changes in the adrenal cortex, spleen, genitals, immunodeficiency. There is evidence for a role of these agents in the development of infertility and neonatal pathology.

[Ecologo-epidemiologic studies in the social-hygiene monitoring system (experience in the Sverdlovsk region)]. / Ekologo-épidemiologicheskie issledovaniia v sisteme sotsial'no-gigienicheskogo monitoringa (opyt Sverdlovskoi oblasti).

Surveys made in the Sverdlovsk Region suggest that a procedure for evaluating a risk in combination with ecological and epidemiological surveys greatly enhances the potentialities of predicting and detecting human environment-related diseases and both approaches deserve a wide introduction into the socio-sanitary monitoring system.

[Use of biologically active substances in preventing the toxic action of some heavy metals]. / Ispol'zovanie biologicheski aktivnykh veshchestv v proilaktike toksicheskogo deistviiia nekotorykh tiazhelykh metallov.

The paper presents experimental and theoretical rationales for some methods and means of biological prevention of the toxic effects of a number of heavy metals (lead, chromium, arsenic, cadmium) that pollute the environment. Subchronic experiments were made on laboratory animals exposed to the above substances in combination with various biological agents (sodium glutaminate, the adaptogen saparal, pectin-containing enterosorbent, calcium, the multivitamin-multimineral preparation Pikovit, etc.). They have indicated that the complex use of preparations is more beneficial than they are used alone. The results of controlled trials of biologically preventive preparations on children residing in an area exposed to industrial pollution are presented.

[Hygienic regulation of welding aerosols in air of workplace and pneumoconiosis in welders (review of literature)]. / Gigienicheskaia reglamentatsiia soderzhaniia svarochnykh aérozolei v vozdukhe rabochei zone i pnevmokonioz élektrosvarshchikov (obzor literatury).

The authors represent review of literature on fibrogenic effects of welding aerosols and results of own clinical and epidemiologic studies concerning pneumoconiosis course in electric welders compared to other occupational groups. In conclusion, the authors necessitate more strict control over total concentration of welding aerosol solid component (WASC) in air of workplace and determination of MAC for WASC.

[Impact of short-term increase in air pollution on mortality of the population]. / Vliianie kratkovremennykh povyshenii zagriazneniia atmosfernogo vozdukha na smertnost' naseleniia.

The authors analyzed whether there is an association of mortality with ambient air pollution analyzed in Yekaterinburg and Nizhni Tagil in 1994 to 1997. There was a positive correlation between general mortality and CO or SO2 concentrations, between cardiovascular mortality and dust, NH3 or phenol, between mortality and CO or NH3. An increase of deaths as percents per 10 micrograms/m3 dust was calculated.

[On hygienic standards of the allowable levels of suspended particles in the air]. / K voprosu o gigienicheskom normirovanii dopustimogo soderzhaniia vzveshennykh chastits v atmosfernom vozdukhe.

Elevation of average daily concentrations of suspended particles in air, even being within the MAC, could be associated with higher mortality in general population and deteriorated respiratory symptoms in children, especially in those having chronic respiratory diseases with bronchial obstruction. Discussion on reduction of MAC for suspended particles is expendient with wider practice of fraction measurement their concentrations.