Polish journal of occupational medicine and environmental health最新文献

Biomarkers of early health effects represent the intermediate stages of the carcinogenesis process, between the initiation and conversion stage and the clinically overt neoplastic disease. The cellular processes indicated by those markers correspond, therefore, to the promotion process. Detection of those cellular processes is extremely important, as the promotion process lasts for many years and bears some signs of being reversible. The promotion process, consisting of a range of consecutive cellular changes involves, among others, activation of proto-oncogens and their transformation into oncogens, and inactivation of the suppressor genes. Therefore, the possibility of observing the trends of those changes by monitoring protein products of the oncogens and suppressor genes in the easily available material (blood, urine) is very useful. Inhibition of intercellular communication seems to play an extremely important role in the complex mechanism of transformation of a normal cell into a neoplastic one. During the carcinogenic process promotion stage, the inhibition is associated with the proteins which form the intercellular junctions and participate in cellular adhesion. That group of proteins includes carcinoembryonal antigen (CEA) and tissue polypeptide antigen (TPA), the tumour antigens which have been known for years. The possible relationship between increased TPA and CEA concentrations is supported not only by the data from the oncology but also by the data from the studies on populations exposed to agents known to increase the risk of neoplastic disease.

Liver damage was induced in rabbits by graded doses of carbon tetrachloride. The damage was assessed by means of quantitative morphometry using necrosis and steatosis of the parenchyma as end points. Biological response was measured utilizing a series of typical biochemical indices of liver damage as well as plasma clearance by the liver 99mTc-mebrofenin (an IDA derivative) and quantified indices of uptake and organ transfer of the compound. No correlation was found between the CCl4 dose and its effect (i.e. degree of necrosis and steatosis of liver). However, a very strong negative correlation was found between the degree of necrosis in individual animals and value of the clearance. The extent of the damage was positively correlated with liver transfer rate of 99mTc-MBF. Plasma activity of ALAT, TG, GGTP and AspAT were higher in the poisoned animals, however, only increments of activity of GGTP, ALAT and LDH showed statistically significant correlation with the individually assessed damage (necrosis).

Hydralazine, dihydralazine and todralazine were tested in the aspect of their mutagenic potency, and the influence upon the mutagenicity of standard promutagen--B(a)P. Hydralazine exhibited strong mutagenic activity in the Ames test while mutagenic activity of dihydralazine was relatively weak. Todralazine had no mutagenic activity, and significantly decreased mutagenicity of B(a)P. It was concluded that todralazine could be a good antimutagenic substance.

The most known result of the influence of the VLF and LF electric fields on a human being is pain due to stimulation of the skin nerves. The threshold of nerve stimulation is related to a value of electric current flowing across a small area of the skin being in contact with the surface of a metallic object. It is shown in this paper that the following set of important parameters corresponds to fingertip threshold perception of the current which from the value of 0.5 mA at 1 kHz increases linearly up to the value of 50 mA at 100 kHz: charge transported across the skin during one duty cycle (0.225 microC), product of the voltage drop on the skin and the surface of the contact electrode (1 mVm2), product of the power dissipated in the skin under the contact electrode and the surface of the contact electrode (0.5 microW m2), electric field intensity of vertical polarization (1.6 kV/m).

One hundred and thirty one workers occupationally exposed to phosphorite and apatite dusts and a control group underwent repeated laryngological and cytological examinations of nasal mucosa smears. The clinical examination showed chronic simple or atrophic rhinitis. The cytological test revealed metaplasia of the respiratory epithelium towards squamous epithelium in all smears. Both the rate of catarrhal changes and the degree of epithelial metaplasia varied with the duration of exposure.

The model of aggregation of 12 parameters describing the environmental and health effects in areas of ecological hazard has been elaborated. The values of particular indices create the characteristic profile useful for selection of dominant environmental problems. The general index of hazard is suitable for establishing priorities among ecological hazard areas.

Genotoxic compounds and various cancer chemotherapeutic agents can interact with tobacco smoke synergistically, especially among cigarette smoking nurses handling cytostatic drugs. The aim of the study was to examine the hypothesis that tobacco smoking has a greater influence on sister chromatid exchange (SCE) frequencies among nurses than the influence of cytostatics in working conditions. The frequencies of SCE in lymphocytes investigated among hospital staff who handle anti-cancer drugs were higher than in a control group which did not handle them (smokers and non-smokers). The increase of SCE frequencies was observed more often among cigarette smoking nurses and less among non-smoking nurses who handle cytostatics 3 times a week.

The present study was designed to investigate methyl-[2,3-14C]acrylate (MA) distribution, excretion, and metabolism. Data presented here show that the radioactivity derived from MA is rapidly absorbed after i.p. and p.o. administration and distributed into all major tissues of rats. The highest concentration of MA-derived radioactivity was detected mainly in the liver and kidneys at 1 (i.p.) or 2 (p.o.) hours after dosing. There were only slight differences observed in the dynamics of tissue distribution and excretion in relation to the route of administration. The major route of MA excretion was CO2 exhalation (approximately 54% of the administered dose in 48 h) followed by urinary excretion. Two metabolites were identified in the urine, namely, N-acetyl-S-(2-methylcarboxyethyl)cysteine and N-acetyl-S-(2-carboxyethyl)cysteine, and ratio between those was about 1:1.

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.