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[Experimental studies to set hygienic standards for benzylpenicillin in the air of a work area].

The character and level of benzylpenicillin toxic effect was studied in accordance with the methodic instruction for performance of the experiments on toxicological estimation and hygienic norms of antibiotics in the air of working areas in production premises. It was shown that the antibiotic was of low toxicity under conditions of a single exposure, did not cumulate and had no local irritating and resorbing effect. It was shown to be an allergen. Prolonged inhalation of benzylpenicillin in a concentration of 14 mg/m3 resulted in reversible changes in the function of the kidneys and liver of the animals, their sensitization and development of pronounced dysbacteriosis of the mouth and intestine mucosa. In a concentration of 1 mg/m3 benzylpenicillin had no general toxic and sensitizing effect but induced reversible changes in the normal autoflora. This allowed the authors to consider the above concentration to be maximum with respect to the antibacterial effect. On the basis of the experiments the maximum permissible norm (MPN) of the aerosol of benzylpenicillin disintegration was recommended at the level of 0.1 mg/m3.

Air Pollutants↗

Cellular method for evaluation of noxiousness of inorganic pollutants in industrial wastes: calculation of a safety index for monitoring sludge discharge.

This article deals with a biological test of safety applicable to industrial wastes. The test is based on the measurement of the growth rate of cultured human cells exposed to waste samples with different dilutions. As a first approach, 15 chemicals in which discharge concentrations are submitted to sanitary regulations were tested one by one. For Zn, Cu, Ni, Cd, Ag, Co, Mg, sulfates, and fluorides, it was possible to detect concentrations that are below the allowed limit. For Hg, Al, As(V), Cr(III), Fe, and Pb, the concentrations that affect cell growth are higher than the allowed limit. Tests were also performed using actual samples (liquid effluent from a laundry and sludge from waste-water treatment plants). Results indicate that, in contrast to chemical analyses, the current biological test has the advantage of providing an indication of global toxicity, integrating all substances and factors that can be harmful to life processes. From the sludge data and the observed threshold of concentration that does not affect cell growth, a numeric safety index has been calculated which indicates the amount of sludge that could be dispersed, as a fertilizer, per hectare of agricultural soil. Such an index could be conveniently used for designing sewage sludge disposal strategies.

Biological Assay↗

[Occurrence of pesticides in apples of varieties from south-east Poland in the years 1986-1989].

In years 1986-1989, a total 445 samples apples of late cultivars were examined. Pesticides were extracted with acetone, whereupon they were transferred to dichloromethane. Extracts were analysed using a gas chromatograph equipped with an electron capture detector and a thermo-ionic detector. Moreover, TLC and colorimetric methods were used. The major part of insecticides and fungicides used for orchard protection were examined. Pesticide residues were present in 248 samples; as a rule, they did not exceed 20% of their allowable concentrations in apples. Thus, the occurrence--in the same sample--of two or more pesticides on this level should entail no risk for the consumer's health. In 19 samples the allowable concentrations of pesticide residues were slightly exceeded; in all cases, only MBC was involved.

Fruit↗