Problemi na khigienata最新文献

Age changes in arterial pressure (AP) and incidence of arterial hypertension (AH), as well as probability of developing IHD, were compared between school teachers and a control group sustaining no excessive occupational stress. The investigated teachers, numbering 168, were from Sofia public schools and technical schools. The control group consisted of 103 women: office employees, designers, research workers, etc. Findings indicated teachers to have a closer age relationship to AP level, compared to controls. Considerable increase in systolic AP was observed after 45 years of age, and there was a significant difference between the first and the second halves of the 4th decade. Diastolic AP was also higher in teachers than in controls. Duration of teaching experience proved to be strongly correlated with systolic and diastolic AP levels (r = 0.56, p < 0.001; and r = 0.50, p < 0.001). Beyond 40 years of age, teachers showed a high incidence of AH, 31%. The group as a whole was at high cardiovascular risk.

The screening of the nervous system function in 42 workers of copper rolled wire [correction of valzdrat] production and in 34 workers of aluminium rolled wire [correction of valzdrat] production was performed in 1992 and 1993 too; 52 healthy military men were investigated as control group. Target neurological anamnesis, internal and detailed neurological status were carried out. Symptoms of radiculopathy, neurasthenic syndrome and signs of generalized neurovegative dystonia were established in both studies--1992 and 1993. It is suggested that an further detailed investigation (including psychometric tests) is needed to verify of refute the neurotoxic effect of copper and aluminium.

This inquiry, carried out in the city of Sofia, covered 247 students with chronic affections and 389 healthy students in the age range 15-18 years. As shown by the results, both student groups gave preference to an environment outside the home and school: they like it better to be among friends, in a friendly circle. In case problems arise, the ambiance of friends is again leading: 16.6% prefer to "share with friends", and only 7.8% "turn for advice to parents". The chronically ill were found significantly more often (p < 0.001) to feel "isolated" and "lonely" among their peers: their social communicability and, respectively, their level of adaptation to an adult environment was negatively affected.

Artichoke, a new Bulgarian preparation based on the plant Cynara scolymus, was tested for influence on sympatho-adrenal system (SAS) activity in experimental inhalation exposure to carbon disulfide. This chronic (six-month) inhalation experiment was done on Wistar albino rats of either sex. Activity of SAS was assessed through excretion of noradrenalin and adrenalin. Findings indicated a phasic SAS response depending on concentration and duration of carbon disulfide exposure. With exposure to 30 mg.m3, SAS activity was observed to decrease in the second month, followed by increase in the fourth and sixth months. With exposure to 300 mg.m3, SAS activity was elevated over the whole period of study. Under the influence of the preparation artichoke at dosage 200 mg.kg-1, catecholamines, increased by carbon disulfide exposure, returned to normal. This trend was more marked for noradrenalin.

A modified spectrophotometric method is proposed for monitoring air concentrations of xylol, toluol, benzol, ethylbenzol, and chlorobenzol. The method has been introduced to control concentrations of the above aromatic hydrocarbons in calibrating indicator tubes, manufactured by the firm "Hygitest", and complies to the specific requirements for that process. There are possible applications in other areas, but further studies would be needed. The proposed method satisfies accuracy and reproducibility requirements. It successfully replaces the more laborious gas chromatographic and IR spectroscopic methods.

The state of adaptation of subjects (numbering 17) occupied at Botev Peak TV relay station and thereby exposed to nonionizing radiations--electromagnetic fields (EMF)--was monitored by following changes in analysis of cardiac variance (ACV) indicators. In addition to these, other physiologic indicators studied were systolic and diastolic blood pressure, as well as psychologic indicators, notably, psychosomatic complaints as early manifestations of disturbance in the state of adaptation. Data from the group of subjects studied were compared to those of a control group whose working conditions involved no EMF exposure. This comparison, based on ACV indicators (mean--mean value of successive cardiac intervals, SD--standard deviation of mean value of cardiac intervals (R-R), AMo--amplitude of the mode, SI, ABI, HI--homeostatic index, CP--classification parameter, IC), psychosomatic complaints, systolic and diastolic blood pressure, provided no evidence of reduction of adaptive reserves or deterioration of somatic and mental health state in occupationally exposed workers at Botev Peak TV relay station.

This paper describes experimental investigations aimed at clarifying the influence of wide-range (white), pulsed and interrupted noise with intensities Lequ 60 and 90 dB (A) on some psychophysiologic characteristics of problem solving. Physiologic indicators were recorded: pulse rate and variance, breathing rate and variance, vascular tone, ets. Psychologic problems to be solved modeled various features of operator activities, including: performing mathematical computations at a given rate; a test involving information processing; a compound option problem offered by Piotkovski's apparatus. Statistical data treatment (t-test of Student and Fisher, and monofactorial dispersion analysis) indicated the masking effect of noise to be more marked in dealing with psychophysiologic problems relating to operative memory. From the physiologic parameters tested, most informative proved to be the changes occurring in peripheral circulation, notably, the rise in vascular tone to peripheral vessels.

Toxic hygienic investigations were carried out involving a representative group of 131 workers (50 females and 81 males) distributed into three main workshops--preparatory, confection, and vulcanization--at "Dynamic" automobile tire plant in Sofia. The majority of male and female workers were in the age range beyond 40 years, having a general occupational experience in excess of 10 years and specialized occupational experience from 10 to 20 years or more. The chemical hazard was among the leading ones in the occupational environment, differing in nature according to the technologies used. Included were various chemical substances and compounds: synthetic rubbers, fillers (soot, chalk, kaolin); softeners (mazut, paraffin, etc.); accelerants (mercaptothiazoles--captax and altax); dithiocarbamates (thiuram); vulcacides (diphenylguanidine); antiwear agents (antioxidants and antiozonators-isopropyl-phenyl-paraphenylene diamine, naphthyl-beta-naphthylamine); antiaccelerants (phthalic anhydride, ets.); organic solvents and others. The indicated chemical substances and compounds, though often found at concentrations below the mean-shift MACs, do produce health impacts by virtue of prolonged and combined exposures. Use was made of the questionnaire method. Also, hematologic, clinical laboratory, and toxic chemical testing was performed. Findings pointed to changes in hemopoiesis, deviations in hepatic functional state, while sulfate and glucuronide values confirmed the workers' high exposures.

Certain properties of the map as a model are briefly examined. Use of the cartographic model in hygiene largely depends on space characteristics of the events and processes being studied. Hygiene as a science introduces into the map new, specific contents and a methodology that includes analysis and evaluation of mapped processes and events from the viewpoint of their impact upon people's health. Based on the events and processes imaged, a concise classification of maps used in hygiene is given.

Changes in selected enzyme parameters were followed in a one year-long toxicologic experiment on albino rat males given vanadium by mouth at either of two dosages: 0.005 mg/kg b.w., which is the equivalent of the regulated level for 1st category drinking water, or 0.01 mg/kg, i.e., twice the safety standard. The endpoints measured included: free sulfhydryl groups in blood serum, heart, and liver; cholinesterase and creatine kinase activities in blood serum; catalase activity in blood; and cytochrome oxidase activity in liver and heart. Chronic oral exposures to vanadium 0.01 mg/kg and, to a lesser extent, 0.005 mg/kg were observed to produce disturbances in redox processes and tissue respiration. The evidence from this study should be taken into consideration when regulating vanadium levels in drinking water from a hygiene standpoint.