Biomedical subjects
Publications and source records attributed to J Krajewski.
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Basing on literature data on toxic effects of oil mist as well as on the results of epidemiological studies, an airborne concentration of 5 mg/m3 of oil mist was suggested as a safe value and 10 mg/m3--as a limit value MAC. Analytical methods used to determine oil mist in the air were surveyed. The fluorescence method was regarded as the best one for evaluation of occupational exposure within low concentrations. Also the determination of polycyclic aromatic hydrocarbons seems to be advisable at the workstations where cutting fluids are used. A number of recommendations wee given aimed at a decrease in occupational risk at work with oils and oil emulsions used as a cooler.
Three methods for desorption efficiencey determination were compared with a reference dynamic method for 12 compounds. Only one of them gave values that were statistically different. The method, in which standard solutions of determined compounds in CS2 are injected onto charcoal, is recommended to all laboratories dealing with air analysis as it is simpler than the dynamic method. Independence of the desorption efficiency on charcoal loading was also confirmed. The desorption efficiences for individual compounds and their mixtures were found to be different.
Experiments with volunteers showed that 42% of an inhaled dose of vinyl chloride is retained in the lungs. This value is independent of the concentration of vinyl chloride in the air. Elimination of vinyl chloride through the lungs is negligible since its concentration in expired air decreases immediately after the cessation of exposure.
Gas chromatographic method was applied to determine the mixture of extraction benzine, benzene, toluene and ethyl acetate vapours. These are the components of several types of butapren glues. Optimum parameters of separation and estimation of those solvents were obtained with 10% Carbowax 20 M on 80 -- 100 mesh Chromosorb W column. Charcoal adsorption method with CS2 elution was used for air samples collection. In addition, a method was presented for extraction benzine calibration with solvents distilled from OBT-III Butapren glue.
A gas chromatographic method for determination of extraction naphtha and benzene has been developed. The best parameters of chromatographic separation were found. Under those conditions it is possible to estimate the total concentration of all ingredients of extraction naphtha as one peak clearly separated from benzene peak. Two methods of calibration curve preparation were considered. One of them consists in preparation of calibration curve from extraction naphtha standard solutions. The other one consists in preparation of calibration curve from standard extraction naphtha vapours adsorbed on charcoal.
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Literature on biological action of mineral oils used as coolants has been surveyed. The data indicate different biological action depending on the origin of fundamental materials and additives used to improve the functional quality. In industry mineral oils may adversely affect primarily the respiratory system and skin. Both investigations of mineral oil aerosols effects in animals and epidemiological examinations of workers exposed to oil mist urgently call for the reduction of oil concentrations in work environment. The irritating properties of oils and oil emulsions vary with quantitative--qualitative chemical composition of those substances. Carcenogenic effects of oils are due to polycyclic aromatic hydrocarbons.
Working environment has been evaluated in PVC plants by air analysis for vinyl chloride concentration. The vinyl chloride emission has been found to vary with the production stage. It has been demonstrated that in the first year of the production, VC airborne concentration largely promoted the risk of developing occupational diseases. The present work conditions may be regarded as admissible and safe. This results from some technological modifications aimed at the reduction of VC emission into the ambient air.
In a selected plant, average airborne concentrations of vinyl chloride were estimated by stationary sampling and autoanalyser. In addition, workers' exposure was estimated by means of individual pumps. The analysis of the obtained results gives evidence that estimation of workers' exposure is correct when sampling is done in the breathing-zone. Average concentrations determined by stationary sampling estimate the environment, but provide no information on workers' exposure. The comparison of the obtained results with the hygienic standard is improper, since the hygienic formation on the values of workers' exposure to vinyl chloride was highly differentiated (from 1.8 to 209.5 mg/m3/8 h) and a positive correlation was found between occupational activities and exposure indices.
A chromatographic method for determining lacquer benzine C in the air has been developed. Appropriate column packing and chromatograph operation parameters have been selected so as to yield summary estimation of all lacquer benzine C components in form of one peak. As a column packing 3% SE-30 has been used deposited on Chromosorb W AW DMCS. This chromatographic method for lacquer benzine C determination is nonspecific when related to xylene and toluene.
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A gas chromatographic method for determination of methyl acetate, ethyl acetate, propyl acetate, butyl acetate and amyl acetate has been elaborated. The best separation of determined compounds has been achieved on a column containing 10% Carbowax 20 M on Chromosorb W AW DMCS. Air samples are collected by passing the examined air through charcoal tubes and consequent desorption of adsorbed compounds with carbon disulfide. Activated charcoal used in all tests has been found to adsorb 10%, by weight, of acetic acid esters.
The paper presents selection of analytical methods for determination of airborne benzidine, whose maximum admissible concentration (MAC) comes to zero. Colorimetric method with T chloroamine, allowing to determine 3 microgram of benzidine in m3 of the air, was evaluated. Such advantages of the method as specificity and availability of reagents and measuring apparatus were stressed. Another method presented in the paper is based on liquid chromatography, and its main features are: much better determinability of--0.7 microgram benzidine in m3 of the air and better precision than that of the colorimetric method. Its usefulness is however limited due to the necessity to have a very expensive liquid chromatograph.
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Heat-acclimated, lightly clothed men and women (four of each) walked on a treadmill at 25% and 43% VO2 max, respectively, (M =194 W.m-2), under seven air temperatures (Ta) ranging from 36 to 52 degrees C. Each experiment involved 1 h of fixed and a 2nd h of progressively increasing ambient vapor pressure (Pa). The relative steady state of rectal temperature (Tre), mean skin temperature (Tsk), and heart rate (HR) reached in the 1st h were forced upward during the 2nd h by the rising Pa. The critical air vapor pressure (Pcrit) was identified by the Tre point of inflection for each Ta. One man did not fully reach steady state, but inflection could be determined for his physiological responses. The mean values of all points of inflection were calculated for Tre, Tsk, and HR. Significant sex difference in HR was found only by excluding the results of the one man. Tre and Tsk showed no significant difference between men and women. The coefficient for evaporative heat transfer (he), which could be derived using the Pcrit for the low Ta range, was 14.5 +/- 2.2 W.m-1 Torr-1.
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