Polish journal of occupational medicine最新文献

The effect of a single exposure to an agricultural insecticide, chlorphenvinphos (CVP), an organophosphorus anticholinesterase, on neocortical seizure activity induced or promoted by cardiazol, and on hippocampal and neocortical EEG was studied in rats. It was found that CVP, given intraperitoneally in doses of 1.0 and 3.0 mg/kg, resulted in no changes in the number and in the duration of epileptic bursts occurring spontaneously, as well as in the content of the hippocampal theta rhythm. The effect of cardiazol (12.5 mg/kg, i.p.) was slightly diminished when the drug was given 3 hours, but not 14 days, after the injection of CVP. I.p. injection of a carbamate cholinesterase inhibitor, physostigmine, in a dose of 1.0 mg/kg resulted in a dramatic increase of the theta content in the hippocampal EEG, and in the total disappearance of the spontaneous seizures. Determination of cholinesterase activity in blood and in the brain in a separate group of subjects showed that after injection of physostigmine (1.0 mg/kg), the inhibition of this enzyme does not exceed the inhibition after injecting CVP in the doses used. It has been suggested that the differences between CVP and physostigmine in their potential to reduce spontaneous epileptic activity and to induce the hippocampal theta rhythm may be due to somewhat antagonistic action of CVP on cholinergic postsynaptic receptors.

Acute toxicity of benzene expressed by survival time and mortality percentage of rats varied in circadian manner. Survival time of rats maintained under standard light/dark (L/D) conditions was significantly shorter when benzene was injected at 20.00 or 24.00, than at 08.00. Simultaneously, mortality of rats was reversed. Inversion of L/D regime of exposure to continuous light abolished all those effects. Rats exposed to continuous darkness showed significantly longer survival time when benzene was administered at 12.00 or 24.00 than when it was injected at 04.00. Generally, acute toxicity of benzene in rats exposed to light was markedly less pronounced than in animals exposed to darkness.

Cholinesterase (ChE) activity in blood (plasma and erythrocytes) and in different parts of the brain, open field behavior and response-to-change in a "T" maze were investigated in separate groups of rats after a single intraperitoneal exposure to an organophosphorus pesticide - chlorphenvinphos. The doses used were 3.0 mg/kg or 1.0 mg/kg which amounted to approximately, 1/3 and 1/10 of LD50 for this species. The exposure resulted in a dose dependent inhibition of ChE in blood, as well as in the brain. No marked differences in the level of ChE inhibition in plasma, erythrocytes, and in selected parts of the brain (cerebellum, brain stem, diencephalon, hippocampus and the anterior part of the hemisphere) were noted after a given dose. In general, 3 hours after the exposure, ChE was inhibited by about 80% in the case of the 3.0 mg/kg dose and by no more than 50% in the case of the 1.0 mg/kg dose. In blood as well as in the brain, the normalization of ChE activity proceeded at a similar rate, being accomplished within 14 days and within 94 hours after the 3.0 mg/kg and 1.0 mg/kg dose, respectively. No changes suggesting an impairment of short-term memory were observed in the "T" maze until the end of testing (i.e. up to the fourteenth day after the exposure). In the open field, a short-term decrease (up to the third day) in locomotor and exploratory activity was observed only in rats exposed to 3.0 mg/kg of the pesticide. At the end of testing (10-14th day after the exposure) the introduction of a new object into the open field resulted in an increase of locomotor and exploratory activity in control animals but not in the rats exposed to chlorphenvinphos in the 3.0 mg/kg as well as in the 1.0 mg/kg. This suggests that exposure to chlorphenvinphos may result in some behavioral disturbances lasting longer than the ChE recovery.

The Medical Service at BASF Aktiengesellschaft in Ludwigshafen began work on introducing an occupational medical information system in 1980. Having developed software for recording acute cases and laboratory results. EPAC was finally introduced in 1989 and integrated into the rest of the system. The aim of the system is to maintain a record of all medical examinations, along with all important personal details and the type of work in which the employee is engaged, the reason for the examination, the diagnosis (and all the factors taken into account in reaching it), and the interpretation of the results from the point of view of occupational medical practice. The details stored in the database provide information on the following: How often is the same diagnosis made for employees in the same type of employment? How does the incidence of diagnoses differ between different groups of employees with different places of work? What is the frequency with which a diagnosis gives rise to a restrictive medical judgement with regard to the employee's work? The opportunities offered by this system for statistical evaluation are discussed with the aid of a few practical examples from the first half of 1989.

Fatty degeneration of the liver is one of the most frequently observed pathological changes in the experimental estimation of the toxicity of chemical compounds. The intensity of this kind of damage is most often detected by means of a generally accepted scale of points, whereas the classification is performed according to the subjective "feeling" of the pathologist. In modern pathological diagnostics, computer analysis of images is used to perform an objective estimation of the degree of damage to various organs. In order to check the usefulness of this kind of method, comparative biochemical and morphometrical studies were undertaken in trichloroethylene (TRI)-induced fatty degeneration of the liver. TRI was administered to rats intragastrically, in single doses: 1/2; 1/3; 1/4; 1/6 and 1/18 DL50. 24 hours after the administration, the animals were sacrificed. The content of triglycerides in the liver was determined according to Folch et al. (1956). Simple lipids in the histochemical samples were detected by means of staining with a lipotropic, Fat Red 7B. The area of fatty degeneration was estimated in the microscopic samples by the use of an automatic image analyser IBAS 2000 (Kontron). The morphometrical data concerning the area of fatty degeneration in the liver amplified a high degree of correlation with the content of triglycerides (r = 0.89) and the dose of TRI (r = 0.96). The degree of correlation between the biochemical data and the dose of TRI was 0.88. The morphometrical studies performed have proved to be of great use in estimating the degree of fatty degeneration in the liver. This method enables precise, quantitative measuring of this sort of liver damage in the material prepared for routine histopathological analysis. It requires, however, the application of a specialized device for quantitative image analysis.

The frequency of dermatitis, oil acne and allergies to chromium, cobalt and nickel in persons exposed to cement, fly-ashes and asbestos cement was studied. The metal content in these materials was assessed. It was demonstrated that the risk of dermatitis and allergy to metals, and especially to chromium, is higher in persons manufacturing prefabricated building products of cement than in those manufacturing them of fly-ashes and asbestos cement, and the risk is similar in persons making products out of fly-ashes and asbestos cement.