Biomedical subjects

E Wiecek

Publications and source records attributed to E Wiecek.

At least 19 recordsLinked to original sources

PubMed2001

[Dust exposure and cancer risk associated with amphibolite mining and processing].

Mining and processing of amphibolite is associated with workers' exposure to dust containing asbestos minerals (actinolite, tremolite) and with the presence of respirable fibers, i.e. small particles above 5 microns long and below 3 microns in diameter (with length-to-diameter ratio higher than 3:1). Results of epidemiological and laboratory studies show that such dust may be responsible for the development of cancer in dust-exposed people. This work reports the measurement results of concentrations of total dust, respirable fibers and mineral composition of samples collected in plant mining and processing amphibolite rock. Based on the results, cumulated exposure was calculated for the 10-, 20- and 30-year exposure periods. The cumulated exposure was classified into two categories: 0.1-1.0 f/cm3 years and 1.0-10 f/cm3. x years. It has been found that mining and processing of amphibolite is associated with increased risk of death from mesothelioma--11.2 x 10(-5) (crushers--10 years of exposure) to 240.0 x 10(-5) (miners--30 years of exposure). The risk of excessive mortality from lung cancer was not high (below 1. x 10(-4)) for all workplaces and periods of exposure.

Adult↗

PubMed2000

[Chrysotile asbestos: biological effects, the work environment highest allowable concentration and neoplasm risk].

The authors present the most essential data on physical and chemical properties of chrysotile, sources of its emission, the extent of occupational exposure, and biological effect, used in setting MAC values for chrysotile-containing dusts. Exploitable asbestos deposits do not exist in Poland, but admixtures of asbestos minerals have been found in some deposits of mineral raw materials located in the area of Lower Silesia (melafir, gabbro, dolomite. ore, nickel, magnesite, serpentinite). In the 1970s, about 100,000 tonnes of asbestos, containing 90% of chrysotile, were used annually in Poland. This figure decreased to 30,000 tonnes in 1991. In 1985 the use of crocidolite asbestos was stopped, and in 1999, the use of asbestos-containing products was banned by the virtue of the legal act. At present, the Minister of Economy in agreement with the Minister of Environmental Protection sets regularly the list of asbestos-containing products permitted for the production or in the customs area. Nowadays, the range of dust concentrations in plants which use asbestos products amounts to 0.1-0.6 mg/m3 for total dust and 0.002-0.07 f/cm3 for respirable mineral fibres; and during exploitation of rock raw material deposits 0.7-280 mg/m3, and 0.01-3.3 f/cm3, respectively. During the years 1976-96, 1520 cases of asbestos-related occupational diseases were diagnosed. This figure included 1314 cases of asbestosis, 154 cases of lung cancer and 52 cases of pleura mesothelioma. MAC values for chrysotile and chrysotile-containing dusts are: 0.2 f/cm3 and 1 mg/m3.

Asbestos↗

PubMed1998

[The evaluation of carcinogenic effect in rats and mice after intraperitoneal administration of refractory ceramic fibers].

The carcinogenic effect of Langfaser and Thermowool ceramic fibres was assessed in Wistar rats and BALB/C mice. Fibres were administered into the animal peritoneal cavity in doses of 25 and 5 mg, and the animals were left for survival. Langfaser and Thermowool ceramic fibres were found carcinogenic. The carcinogenic properties of Thermowool ceramic fibre can be compared to those of Krokidoit UICC asbestos.

Animals↗

PubMed1997

[Problems associated with setting maximum allowable concentrations (MAC) of harmful substances present in the work environment].

The major aim of setting MAC values is to reduce the risk of occupational exposure to harmful substances to the acceptable level. In the process of setting MAC values, a critical analysis of the toxicological and medical literature, used by teams of experts who try to estimate the probability of health effects with different concentrations and different duration of exposures, is most essential. This process is usually very difficult since the epidemiological data and the results of animal experiments are often incomplete, and extrapolation of experimental results from animals to humans entails a lot of doubts. Moreover, one never knows which level of the risk can be considered as acceptable. That is why MAC values set by groups of experts cannot be treated as absolutely safe to the human health. They should be verified if new data on biological effect of substances harmful to health and new criteria for occupational risk assessment become available.

Animals↗

PubMed1996

[Exposure to dust mixtures containing free crystalline silica and mineral fibers].

Exposure to dust mixture containing at the same time respirable mineral fibres and free crystalline silica may occur in Poland in mines and in the Lower Silesia plants processing mineral raw materials as well as in all plants which use asbestos products and MMMF. Workposts where thermal insulation is exchange with possible phase transformations during operations under conditions of high temperature, expose particularly complex problems. In the work environment of this kind, dust concentration of free crystalline silica becomes important but not sufficient criterion for evaluating working conditions and it may be misleading. A range of studies indispensable for the proper evaluation of exposure to dust, covering together with measurement of dust and SiO2 concentrations, determination of the mineral composition of dust, was developed. It was also found that the acceptable level of risk for neoplastic disease, namely 10(-3) can be attained in the work environment only if the concentration ranges from 0.05 to 0.1 f/cm3, that is equal to 20% of MAC value which is now binding in Poland. Cancer risk (lung cancer and mesothelioma jointly) during a 20-year exposure to concentrations equal to present MAC values should be estimated as about 10(-2) what indicates that risk is too high and it is necessary to diminish MAC values for asbestos dust.

Dust↗

PubMed1996

[Refractory ceramic fibers, kinds, health effects after exposure, TLVs].

Ceramic fibres are amorphous or crystalline synthetic mineral fibres which are characterised by refractory properties (i.c. stability in temperature above 1000 degrees C). In general, ceramic fibres are produced from aluminium oxide, silicon oxide and other metal oxides and less frequently from non-oxide materials such as silicon carbide, silicon nitride and boron nitride. In Poland, the production of ceramic fibres was begun in the Refractory Materials Plant, Skawina, during mid-eighties. The production capacity accounts for about 600 tons annually. It is estimated that approximately 3000 persons are exposed to the effect of ceramic fibres in Poland. During the production of ceramic fibres, concentrations of respiral fibres in the air at work places range from 0.07 to 0.27 f/cm3; during the manufacture of ceramic fibre products from 0.23 to 0.71 f/cm3 and during the application of ceramic fibre products from 0.07 to 1.67 f/cm3. As published data depict, fibres longer than 5 microns are most common in the work environment, and the proportion of fibres with diameters below 1 micron accounts for 40-50%. Bearing in mind the present situation in Poland, namely combined exposure to asbestos (during removal of worn out heat-insulating materials) and ceramic fibres (during installation of new insulation), as well as in view of own investigations and literature data which evidence a strong carcinogenic effect of certain fibres, the following MAC values have been adopted: Dusts of refractory ceramic fibres: total dust-2 mg/m3; respirable fibres-1 f/cm3 (L > 5 microns; D < 3 microns; L: D < 3:1) Dusts of reflactory ceramic fibres mixed with asbestos: total dust-1 mg/m3; respirable fibres-1 f/m3. Dusts of refractory ceramic fibres mixed with other man-made mineral fibres (MMMF): total dust-2 mg/m3; respirable fibres-1 f/m3. According to the IARC, ceramic fibres have been included into group 2B-suspected human carcinogen.

Adult↗

PubMed1995

[Exposure to mineral fibers in selected ceramics plants].

The aim of the work was to check, in the selected ceramic plants, whether the replacement of asbestos heat-insulating material by mixed material or fibrous material free from asbestos decreased the risk of exposure to mineral fibre dust among workers engaged in the overhaul of furnace trucks and ceramic furnaces. In the 6 selected plants which used various heat-insulating materials, dust concentration was measured (personal dosimetry), composition of mineral dust, collected from air at overhaul posts, was identified (RTG and IR methods), and morphology of dust particles was examined (optic microscopy and TEM). The highest concentration of respirable mineral fibres was found during the overhaul of a truck with asbestos insulation; respirable fibre concentration reached the value of 5 f/cm3, and total dust concentration-the value of about 80 mg/m3. Insulating plates made of asbestos paper-board proved to be the major source of the mineral fibre emission; mean weighted dust concentration in the plants under study ranged from 2.0 to 2.7 f/cm3. The replacement of asbestos plates by plates made of other heat-insulating materials have lowered respirable mineral fibre dust concentration by ten times. In dust samples collected from the air at the overhaul workposts, the presence of chrysotile, forsterite, quartz and cristobalite (asbestos heat-insulating materials) as well as cristobalite and mullite (non-asbestos heat-insulating materials) was found.

Air Pollutants↗

PubMed1995

[Amorphous silica. Types, health effects of exposure, NDS].

Maximum allowable concentration (MAC) values for amorphous silica dust have not been identified in the Polish legal regulations up-to-date. In this work the authors review values of allowable (recommended) amorphous silica dust concentrations in other countries. Data on other types of amorphous silica (natural and synthetic) used in industry as well as data on health effects of exposure to these types of dust are presented. The work encompasses 42 entries in the references and one Table which includes the following proposed MAC values: Non-calcinate diatomaceous earth (diatomite) and synthetic silica: Total dust--10 mg/m3 Respirable dust--2 mg/m3 Calcinate diatomaceous earth (diatomite) and fused silica (vitreous silica): Total dust--2 mg/m3 Respirable dust--1 mg/m3.

Diatomaceous Earth↗

PubMed1994

[Respirable mineral fibers in atmospheric air of Wrocław].

Serpentine asbestos from the Naslawice mine, which contains mineral impurities of the serpentinite group--chrysotile and antigortie, has been used to built school sports grounds as well as roads and playgrounds within residential areas. The study was aimed to measure concentrations of respirable mineral fibres in the atmospheric air at the time children were playing on one of the playgrounds as well as at four other sites of Wroclaw. Air samples were collected using individual dosimeters and distributions of length and concentration of fibres were measured by means of a laser fiber monitor FM7400. X-ray diffraction and infrared spectrometry were used to determine the mineral composition of raw material collected from the playground. Morphology of particles of dust from the atmospheric air was analysed by means of electronic microscopy. It was found that the concentration of mineral fibres in the air in question depended on the number of children playing, namely when 7 children were playing the concentration value was equal to 165 fibres/litre and 549 fibres/litre with the number of 20 children. The concentration of fibres in a flat in the vicinity of the playground covered with serpentinite was about 11 times higher than at a street crossing with heavy traffic of motor vehicles. Antigorite and chrysotile were found in samples of raw material used to cover the playground. Numerous particles of fibrous structure were observed in the electronic microscopy image of air dust samples collected from the playground.

Air Pollutants↗

PubMed1993

[Effect of water sprinkling on total dust and mineral fiber concentration during serpentine asbestos processing].

By means of personal air sampler and Fibre Monitor FM-7400 concentrations of total dust and respirable mineral fibre were measured at work-posts, after sprinkling places with the highest emission of dust, in the plant where serpentine asbestos, used as road stone, was processed. It was found that due to sprinkling mean concentrations of total dust during a shift decreased by 1.5 (at inspection post) to 13.5 times at the post where crushing and sorting machines were served (before sprinkling -29.7 mg/m3 and after 2.2 mg/m3). It was found, at the same time, that sprinkling no decreased the concentration of mineral fibres.

Air Pollutants↗

PubMed1993

Experimental carcinogenicity and mutagenicity of non-asbestos natural fibres--preliminary report.

The aim of this investigation was to quantify the carcinogenic and mutagenic activity of antigorite occurring in the form of admixtures in different mineral raw materials (serpentinite, magnesite, dolomite and nickel ore). The carcinogenicity of dusts was evaluated after intraperitoneal injections of 5 mg (mice) or 20 mg (rats) of dust suspended in saline. A pathomorphological examination was performed in all the dead animals. For two raw materials--serpentinite and nickel ore--their mutagenic potency was investigated (SCE test was used in this study). Results obtained in the experiments on animals (rats and mice) showed that the biological aggressiveness of the mineral raw materials tested was associated with the content of antigorite fibres. Particularly the frequency of mesothelioma (5-85%) was related to the number of antigorite fibres longer than 5 microns. Both of the investigated raw materials (serpentinite and nickel ore) were mutagenic in the SCE test.

Animals↗

PubMed1992

[Various ecological problems related to mining and processing of serpentine. Evaluation of non-occupational exposure of the population of Nasławice to fibrous mineral dust].

Non-occupational exposure of the population living in the vicinity of the serpentine mining and processing mill in Nasławice was assessed. The evaluation was based on the phase analysis and determination of respirable mineral fibres content in the samples of dust fall and soil in the fields nearby the mine, as well as on the in-door and out-door measurements of airborne fibres concentration. All soil samples contained antigorite--a mineral the structure of which is close to that of chrysotile asbestos add exhibiting high biological aggressiveness. The respirable mineral fibres content in the dust fall-out and in the soil ranged from 98,000 to 480,000 per 1 mg and from 48,000 to 122,000 per 1 mg, respectively, whereas the airborne concentrations were from 2 to 1540 fibres/l (outdoor) and from 4 to 7 fibres/l (indoor). The fall of dust in the years 1989-1990, recorded at all measuring points, exceeded 200,000 kg/km2 yearly (admissible value). The airborne concentrations of respirable mineral fibres were also higher than the admissible value (1 fibre/l of the air). The results obtained indicate that the exposure of the population in Nasławice to mineral fibrous dusts has significantly exceeded to maximum admissible concentrations established for non-occupational exposure.

Air Pollutants↗

PubMed1992

[Asbestos substitutes and their biological effects. 2. Synthetic amphiboles--their physico-chemical characteristics].

Metal content in the chemical structure of asbestos and man-made mineral fibres can affect their carcinogenic properties. As the chemical composition (metal content) of man-made silicate substitutes for asbestos can be varied almost at will in the process of their manufacture, the search for potentially least carcinogenic silicates appears to be of utmost importance. This paper presents diffractometric characteristics, dimensional analysis and morphology data for 4 synthetic amphibole fibres with chemical compositions differing from that of natural crocidolite amphibole. Those included the following synthetic amphiboles: Na2Mg6Ge8O22(OH)2; Na2Ni6Si8O22(OH)2; Na2Mg6Si8O22(OH)2; Na2Co6Si8O22(OH)2. The studied amphiboles differed in fibre length and diameter. The magnesium amphibole contained the longest (6.03 microns) fibres, and the nickel amphibole contained the shortest (2.7 microns) fibres, resembling those of crocidolite. The highest content (54.7%) of respirable fibres was found in the magnesium amphibole, and the lowest (15.9%) in the natural crocidolite. The authors suggest that the detected differences in the physical and chemical characteristics of the synthetic amphiboles may affect their biological properties.

Asbestos↗

PubMed1992

[Asbestos substitutes and their biological effects. 3. Carcinogenic effects of synthetic amphiboles in animal experiments].

This work presents the results of the test performed on rats to evaluate the carcinogenic effect of 4 synthetic amphiboles compared to that of the natural amphibole--crocidolite. The dose of the magnesium amphibole (Na2Mg6Si8(OH)2) administered to the animals contained 240 x 10(6) respirable fibres; the corresponding value for the nickel amphibole (Na2Ni6Si8O22(OH)2) was 339 x 10(6), for the cobalt amphibole (Na2Co6Si8O22(OH)2)--1000 x 16(6) for the geranium amphibole (Na2Mg6Ge8(OH)2)--250 x 10(6), and of the natural crocidolite amphibole (Na2Fe2Fe3Si8O22(OH)2) x 380 x 10(6) respirable fibres. The control animals (rats) received physiological NaCl solution. The number of peritoneal mesotheliomas following single intraperitoneal administration of 20 mg of the dust was adapted to be the measure of the carcinogenic activity of the dust. 3 synthetic (magnesium, cobalt and nickel) amphiboles and crocidolite caused development of malignant peritoneal mesothelioma in 11.1% to 71% rats. The results show that there is a relationship between the chemical composition of the synthetic amphiboles and their carcinogenic effect. Out of 4 investigated synthetic amphiboles, the magnesium amphibole, which contained magnesium and silicon, displayed most severe carcinogenic effect. The synthetic amphiboles containing either silicon and cobalt or silicon and nickel displayed 8.3 and 6.2 times weaker ability to induce peritoneal mesothelioma.

Animals↗

PubMed1992

[Asbestos substitutes and their biological action. I. Types, use, exposure and MPEL].

Referring to literature, the authors present problems of exposure to asbestos, its production and MACs in Poland. In our country artificial mineral fibres are produced in seven plants employing about 2000 workers. These plants produce basalt wool, sag wool and glass fibres used in industrial and building insulating materials and in cement and mortar additives and as a free insulating material. Mean concentrations of total dust at the work-posts measured in 1986-1989 ranged between 1.06 mg/m3 and 3.10 mg/m3. Concentrations of respirable fibres ranged from 0.041 fibre/cm3 to 0.173 fibre/cm3. In Poland, the MAC for mineral fibres for total dust amounts to 4 mg/m3 and for respirable mineral fibres to 2 fibres/cm3.

Air Pollutants, Occupational↗

PubMed1992

[International control of the quality of microscopic-numerical analysis of the levels of man-made mineral fibers (MMMF) in the air of the work area].

In the years 1986-1990 the Institute of Occupational Medicine in Lodz (Department of Aerosols) participated in seven exchanges of preparations within the WHO/Euro MMMF Reference Scheme programme. The number of persons analysing the preparations increased from three, during the first exchange, to seven in the sixth. Markings in the 1st and 3rd exchange constituted two thirds of the reference markings. In the 2nd, 5th and 7th exchange the markings were similar, and in the 6th exchange they were lower than in the reference markings. According to the accepted system, the markings of the standardized density in four exchanges (2nd, 5th, 6th and 7th) were determined as class I (0.70-1.40), and in the remaining exchanges (1st, 3rd and 4th) of class II (0.50-2.00).

Air Pollutants, Occupational↗

PubMed1991

[Maximum permissible levels of asbestos and other natural minerals with fibrous structure--necessity of verification].

MACs of asbestos are from 2 to 20 times higher in Poland than in other Western Europe countries. The analysis of occupational diseases reported between 1983 and 1988 among workers of asbestos-cement plants has showed that Polish MAC values do not protect people from work-related asbestosis. Asbestosis was frequently diagnosed in workers employed at mining and processing of nickel ore containing admixtures of fibrous antigorite. The risk of asbestosis in workers of a nickel++ metallurgical plant was 8 times higher that in those employed at an asbestos-cement plant. In an animal study, fibrogenic, carcinogenic and mutagenic activity of antigorite was similar to the biological aggressiveness of crocidolite. Based on own studies and literature data, the following MACs for asbestos and other natural fibrous minerals were established: a) for dusts containing asbestos and other fibrous minerals except crocidolite and fibrous antigorite, total dust concentration equals 1 mg/m3 and concentration of fibres longer than 5 microns = 0.5 fibre/cm3 b) for dusts containing crocidolite and fibrous antigorite total dust concentration = 0.5 mg/m3 and concentration of fibres longer than 5 microns = 0.2 fibre/cm3.

Air Pollutants, Occupational↗

PubMed1991

The fibrogenic activity and neurotoxicity of heat-treated chrysotile.

Thermal degradation of heated chrysotile results in dehydration and changes in its crystalline structure. The impact of heat treatment at 150-1200 degrees C on the biological activity of chrysotile was tested in rats. Heating the chrysotile produced an increase in its biological aggressiveness measured in terms of animal survival rate and fibrogenic activity after intratracheal administration of the dust. The highest death rate (100% of the animals) was noted after administration of chrysotile heated at 600 degrees C. Moreover, increased fibrogenic activity of chrysotile heated at 150 degrees C up to 800 degrees C was found. The biological effect of chrysotile heated at 1200 degrees C did not differ from the effect exerted by unheated chrysotile. After intraperitoneal administration of the dust, the most violent reaction could be observed when chrysotile dust was heated at 600 degrees C, which resulted in symptoms of nervous system impairment (of the hind legs, no reaction to nociceptive stimuli, drop of internal body temperature) and death of the test animals. In male rats, the period between dust administration and the manifestation of symptoms and death was found to be longer than in females.

Animals↗