[An experimental study of a microbiological index in the complex setting of standards for lead, copper and zinc in the soil]. / Eksperimentalno prouchvane na mikrobiologichniia pokazatel pri kompleksno normirovanie na olovo, med i tsink v pochvata.

Anthropological pollutions falling in the soil by different routes evolve multitude unfavourable consequences for human being and health. The present publication considers a laboratory survey on the influence of lead, copper and zinc by their combined presence in soil onto soil autocleaning ability. The results from the experiments will serve the goals of complex hygiene standards of these three soil pollutants. A number of micro-organisms, relating to soil as an ecological compartment, are tested by two hygienic microbiological methods. The results from experiments point out as maximum permissible concentration (MPC) the following combination of concentrations within the range of the microbiological index: lead--54 mg/kg, copper--90 mg/kg, zinc--165 mg/kg. Concentrations over the above-mentioned have an oppressive effect on saprophytic microflora in higher rate than the observed impact of pathogenic micro-organisms. In conditions of MPC higher than the reached ones the autocleaning ability of the soil is threatened and thus a basis with unfavourable epidemiological indicators is established.

[The hygienic characteristics of the hospital environment in a cardiovascular pathology ward during the heating season]. / Khigienna kharakteristika na vutrebolnichnata sreda v otdelenie za surdechno-sudova patologiia prez otoplitelniia sezon.

A study is carried out on the microclimate, physiological reaction of patients, chemical and bacteriological composition of the air in rooms of different location in the ward for cardiovascular pathology during the heating period of the year, according to some basic and integral indices. The characteristics of the interhospital environment in the rooms of the investigated ward is determined mainly by the irrational regime of heating, location, size of the glazed transparent area. In the hospital rooms are formed unsatisfactory hygienic norm parameters of the microclimate and the chemical composition of the air. The specific thermal environment affects the physiological reactions of the patients and leads to creation of conditions of discomfort and loading of the thermoregulation in direction of overheating.

Experimental study of subacute oral, dermal and inhalation toxicity of bulmoscide preparation.

The purpose of this study is to give the toxicological characteristics of subacute oral, dermal and inhalation exposure of microbial preparation Bulmoscide, which is based on bacterium Bacillus thuringiensis, serotype H-14. The study was performed on sexually mature Wistar rats of both sexes. No significant changes in non-specific, clinico-laboratory and biochemical parameters as well as morphological examinations in any tested groups compared to the control groups were revealed. The doses 110 mg.kg-1 (1.32 x 10(9) sp.kg-1) at oral administration in duration of 90 days, 3000 mg.kg-1 (3.6 x 10(10) sp.kg-1) in 21 day dermal application and maximum attainable concentration of dust aerosol 18 mg.kg-3 (2.2 x 10(8) sp.m-3) during a 30 day inhalation exposure are "no toxic effect" levels. On the basis of the data, the selective bacterial insecticide Bulmoscide has been determined to be of low toxic and low hazardous preparation in compliance with the Hygiene Classification of pesticides.

[The acute toxicity of the microbial preparation bulmoscide]. / Izsledvane na ostrata toksichnost na mikrobniia preparat bulmostsid.

The acute toxicity of a new Bulgarian microbial preparation bulmoscid on the basis of Bacillus thuringiensis H-14 in the conditions of oral, dermal, inhalation and intraperitoneal introduction in experimental animals is determined. The assessment of toxicity is made by using toxicometric, integral, hematologic, histologic and microbiologic methods in accordance with Bulgarian and international criteria and standards. It is established, that the preparation bulmoscid introduced orally in dose 5500 mg.kg-1 (6.6.10(10) cell kg-1), applied dermally in dose 6000 mg/kg-1 (7.2.10(10) cells kg-1) and in concentrations 18 mg.m-3 (2.2.10(8) cells m-3) for 14 day inhalation exposure, provokes no lethal exit and symptoms of intoxication and leads to no changes in the integral, hematologic and histologic investigations on experimental animals. The preparation belongs to the practically nontoxic substances. The studies of the acute toxicity show, that the microbial preparation bulmoscid offers no danger for appearing of oral, dermal and inhalation poisonings when observing the regulations for its production and use.

[A hygienic study of new raw materials for cosmetic agents and household chemical preparations]. / Khigienno prouchvane na niakoi novi surovini za kosmetichni sredstva i preparati na bitovata khimiia.

Studies are performed on the new Bulgarian raw materials "Aminookis" (AO) and "Dezodorirashch agent" (DA) the plants "Alen Mak"--Plovdiv and "Hyaluron"--Sofia. Chemical, toxicological and microbiological studies are carried out. Thin-layer chromatographic and spectrophotometric methods for determination of AO, hyaluronic acid and DA are developed and chemical studies on cosmetics, prepared with them, are carried out. During the repetition of a 21-day experiment on guinea pigs the threshold irritative concentrations--10% for AO and DA (as trade products) are determined. This shows that they are moderate contact irritants. The hyaluron has no irritative effect. By maximizing test with guinea pigs is established the absence of contact allergy for DA and AO. At index of sensibilization 10% the hyaluron falls in the group of weak allergens. The spectra of action are studied and the minimum suppressing concentrations of AO and DA are defined. It is established that the most resistant to effect with these cosmetics are the representatives of the families: Pseudomonas, Klebsiella, Escherichia, Salmonella. Recommendations are made to use "Aminookis" (AO) in shampoos to 8%, deodorizing agent in deodorants to 2% and "Hyaluron" in creams to 20% (as trade products).

[Microbial contamination of the work area air at the tricot knitting mills]. / O mikrobnoi obsemennosti vozdushnoi sredy proizvodstvennykh pomeshchenii z trikotazhnykh predpriiatii.

The study carried out during cold and warm periods of the year covered 2 knitting mills situated in different regions of Bulgaria. Workplace air microflora was characterized by a higher level of bacterial and fungal contamination during the warm period of the year compared to the cold one. Dust content in the work zone was analogous to that of microorganisms. Disease rate, its dynamics and structure were analyzed in order to determine the impact of air microbiology on workers' health status.

[Virulence of the microbial preparation Bactorodencide for various animal species]. / Virulentnost na mikrobialniia preparat "Baktorodentsid" za razlichni vidove zhivotni.

The virulence of the biological preparation for plant protection Bactorodencite is studied in 6 species of wild and domestic animals and game. Its high specificity concerning rodents is established at the highest rate in Ratus Norvegicus and inbred mice - C57 Black. Indocile to S. enteritidis var. issatschenko (active start of the Bactorodencite) are the grey pigeons, hens, ducks, pheasants, lambs and pigs. The time for clearing the organism of the indocile animals depends on the quantity (dose) absorbed bacteria, the specy of animals, and is not longer than 18-20 days.