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Unlabelled: The present study is a part of a larger project on assessment of exposure to biological agents and respiratory health effects among metal workers., Objectives: The aim of this study was to evaluate the level of microbial contamination of metalworking coolants as a potential source of harmful biological agents in three different metal industry plants in Poland., Material and Methods: Ten samples of coolants with a different state of wear, including four fresh fluids, were analyzed. Qualitative and quantitative analysis of bacteria and mould content was performed using standard analytical methods. Bacterial endotoxin concentration was determined by the kinetic, chromogenic version of the LAL test., Results: The analysis showed the total bacterial counts ranging from 1.0x10(1) CFU/ml to 3.2x10(7) CFU/ml, 60% to 100% of which were Gram-negative bacteria capable of producing endotoxins. Among the highly contaminated coolants, one unused concentrate was also found. The predominant species of bacteria was Shewanella putrefaciens present in 60% of the samples. As for moulds, the predominant species was Acremonium butyri. The average concentration of bacterial endotoxins was 773 EU/ml in the old coolants, and much lower in the fresh fluids 285 EU/ml. A correlation (r=0.66) was found between endotoxin concentration and the number of Gram-negative bacteria detected in the coolants., Conclusion: Procedures should be developed for cleaning tanks during fluid replacement to minimize the risk of bacterial growth in the coolants and limit bioaerosol emission in workplace. Due to the affinity of microflora for the water phase, it is advisable to use effective biocides with appropriate partition coefficient between the water phase and oil phase.

Background: The aim of the study was to quantitatively and qualitatively identify moulds occurring in the air of selected office rooms., Material and Methods: The study was conducted in the wintertime inside four office rooms with moisture trace and one control room. To assess mycological contamination of the air, triple samples were directly collected on Petri dishes (Malt Extract Agar medium) using a Burkard air sampler. Qualitative evaluation of moulds was based on the microscopic view and morphological features of colonies., Results: Total number of moulds determined in the air of office rooms did not exceed the level of 4 x 10(2) cfu/m3. The highest concentration of moulds (3.44 x 10(2) cfu/m3) was found in the room that was also used as an archive. It was over tenfold higher than in the control room (0.33 x 10(2) cfu/m3). The qualitative analysis of moulds showed the presence of 15 species. Some of them, including Aspergillus fumigatus, Aspergillus versicolor, Aspergillus ochraceus, Cladosporium spp., Penicillium spp. and Alternaria spp., are recognized as potential health hazards to workers due to the production of mycotoxins and allergic reactions., Conclusions: The archive was the only room, where concentration of moulds slightly exceeded the reference value. To protect the health of workers who perform their duties in this place, the documents, which are an ideal place of mould growth, should be moved to a separate room. Respiratory complaints reported by workers could be associated with concentrations and species of moulds found in the office rooms under study.

In metalworking, the temperature of the cutting edge can reach 700 degrees C, which can adversely affect either the surface of the metal processed or the cutting edge itself. To reduce the heat and friction, the metalworking fluids and coolants are used. The most common are the oil-in-water emulsions, which are a mixture of concentrated mineral oils, different additives, and water. The presence of water and organic substrates generates conditions for microbial growth. Bacterial endotoxins can also be frequently detected in metalworking fluids. Rapid rotation of the metalworking tools makes various biological agents to be released as droplet bioaerosols that can be inhaled by the workers, thus producing adverse health effects, mainly on the respiratory system. More than 130 species of bacteria (including pathogens), moulds and yeasts have so far been found in the metalworking fluids and coolants. This paper summarizes the outcomes of projects on the impact of biological agents present in metalworking fluids. Exposure to oil mist, bacteria and endotoxins as well as the variety of health effects resulting from that exposure have been discussed. The findings indicate that the most frequent symptoms reported by the workers include cough with phlegm, wheezing breath, chest tightness and throat irritation. The most common among the diagnosed diseases are chronic allergic bronchitis, asthma, hypersensitivity pneumonitis and acute respiratory dysfunction indicated by decreased FEV1 values. The main skin diseases include oil acne, bacterial infections, dermatomycosis and allergic reactions. The review made the authors conclude that the problem of occupational exposure to biological agents released with coolants during metalworking has not been well recognized in Poland.

Background: The purpose of the study was to evaluate exposure to bioaerosols among sewer workers., Materials and Methods: The study was carried out in the summertime, based on the standard PN-EN 13098. Air samples were collected on gelatine filters at three stationary sites: inside the sewer, next to the sewer manhole during under pressure cleaning and at effluent discharge point. In collected samples the qualitative and quantitative analysis of bacteria and fungi were performed., Results: Bacteria and fungi concentrations were at low levels. The highest concentration of bacteria (about 5.0 x 10(2) cfu/m3) was found inside the sewer and of fungi (about 1.0 x 10(2) cfu/m3) at effluent discharge point. Among all determined microorganisms Gram-positive bacteria were predominated, especially Staphylococcus lentus. Others bacteria there were also found, like rod-shaped of the genus Bacillus and Enterococcus faecalis. The diversification of Gram-negative bacteria was small. Among fungi there were determined representatives of two genera Aspergillus spp. and Penicillium spp., including species Aspergillus fumigatus., Conclusions: According to the law in force among all determined microorganisms only bacteria Enterococcus faecalis (Enterococcus spp.) and mould Aspergillus fumigatus are classified as harmful biological agents (occupational risk group 2). It is suggested using by employees personal protective equipment, especially for respiratory airways and skin protection and also keeping the rules of individual hygiene.

Background: In the construction industry, free crystalline silica (FCS), mostly in the form of quartz, is in a very common use. Construction, especially repair and demolition works, are associated with emission of considerable amounts of FCS-containing dusts. Studies concerning the work environment, carried out recently in other countries, indicate that exposure to quartz frequently exceeds hygiene standards, i.e. safety limits for workers' health. The aim of this study was to assess dust exposure of workers employed at selected workposts in the construction industry in Poland., Material and Methods: The Polish study was performed in a group of workers employed in large and small enterprises and involved in establishing new constructions and demolishing old buildings. The group comprised 43 workers, employed at 9 workposts, who underwent 107 measurements of dust concentrations, of which 78 measurements were included in the analysis. At each workpost, concentrations of inhalable and respirable dusts were measured with the filtration and gravimetric method. Individual dust dosimeters were used to collect air samples and infrared spectrometry to determine concentrations of FCS dusts in samples of inhalable and respirable dusts. An identification analysis of dust samples was performed with use of X-ray diffraction., Results: The results of the study show that geometric means of inhalable dust concentrations fell within a wide range from 2.1 (concrete mixer operator, plasterer) to 66.0 mg/m3 (laborer engaged in hand demolition), and those of respirable dust at the same workposts ranged from 0.4 to 16.2 mg/m3, respectively. Quartz was present in the majority of construction materials applied, and its concentration in inhalable dusts ranged from 7 to 13 mg/m3., Conclusions: It was found that dust concentrations exceeded hygiene standards at most of the workposts. Particularly high concentrations were observed at the workposts of surface abrasive grinders-coat finishers and workers engaged in drilling and hammering wholes. In conclusion, the need to use technical means, primarily personal respiratory protectors, to reduce dust concentrations should be strongly stressed.

Objectives: The aim of the study was to assess the microbiological air quality at the selected municipal waste landfills., Materials and Methods: The study was conducted during the summer at two municipal landfills. Air samples were collected on agar plates. The evaluation was based on the concentration levels of airborne bacteria and fungi and the identification of isolated strains., Results: The total number of bacteria and fungi did not exceed the level of 10(3) cfu/m3. The highest concentrations of bacteria in air were observed during unloading, disposing and compacting of municipal wastes (landfill 1 - 6,1 x 10(3) cfu/ml, landfill 2 - 5,4 x 10(2) cfu/m3). The highest concentrations of fungi in air were observed at filled up parts of the landfills (landfill 1 - 4,8 x 10(2) cfu/m3, landfill 2 - 1,2 x 10(3) cfu/m3). The qualitative analysis of the air samples indicated the presence of 21 bacterial and fungi. Among of them bacteria Enterococcus faecalis, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis and fungi Aspergillus fumigatus, Candida albicans are classified as harmful biological agents., Conclusions: The total number of bacteria and fungi in air samples collected at the selected municipal waste landfills did not exceed the reference values. The concentration levels of bioaerosols are diversified according to the size of the landfill, the total number of accumulated wastes and the level of area usage. It is suggested using by municipal waste workers personal protective equipment, especially for respiratory airways and skin and also keeping the rules of individual hygiene.

Background: Health care workers belong to a high risk occupational group in view of their permanent contact with biological agents. It is essential to take all available and effective technical, organizational and medical preventive measures to protect the exposed workers., Methods and Materials: Activities aimed at protecting workers from risks related to exposure to biological agents, according to recommendations laid down in Directive 2000/54/EC, were assessed in a questionnaire survey carried out in 47 hospitals., Results and Conclusions: The following requirements were best satisfied by the hospitals under study: provision of workers exposed to biological agents with collective and personal protective measures; washing and toilet facilities; separate dinning rooms; registration of accidents involving handling of biological agents and including biological agents issues in the program of occupational training of workers. Most flaws and oversights were observed in regard to: biological agents risk assessment; appropriate marking of rooms where biohazard may occur; written procedures for safe handling of biological agents and the implementation of vaccination program against hepatitis B.

Objectives: The aim of the present project was to assess population exposure to pesticides in the vicinity of pesticide dump sites and make a preliminary evaluation of the potential health hazards to humans., Materials and Methods: Of the 286 pesticide dump sites registered in Poland, 40 were selected as the largest source of ecological hazard. The application of the Hazard Ranking System made it possible to identify 17 priority dump sites where pesticide wastes are deposited. For population exposure assessment, two dump sites located close to the residence area and drinking water intakes were selected as potentially most hazardous to health. They have a piezometric system installation that enables ground water sampling for analysis., Results: In water samples collected from the water-bearing layer in areas adjacent to pesticide dump site, 31 different pesticides in total have been detected (15 organochlorine pesticides, 10 organophosphorous pesticides and 6 phenoxyacids), 12 of which - dichlorvos, mevinphos, endosulfan, dieldrin, heptachlor epoxide, p,p'-DDT, p,p'-DDD, p,p'-DDE, methoxychlor, 2,4-D, MCPA, MCPP--had concentration levels higher than the detection limit. The estimated size of the potentially exposed population approximates 900 inhabitants; 33% of this population are children (aged 0-14 years) and women at reproductive age (aged 15-45 years). Both these target populations are considered particularly susceptible to the adverse health effects of pesticides. Assessment of population exposure to pesticides (p,p'-DDT - 0.15 microg/l; p,p'-DDD - 0.13 microg/1; MCPP - 12.3 microg/l; MCPA - 0.64 microg/l; methoxychlor - 0.31 microg/l; 2,4'-D - 5.4 microg/l) with concentration levels higher than the drinking water standard (0.1 microg/1) was based on pesticide daily intake in drinking water., Conclusions: The results indicated a low cancer risk (R = 10(-8)) for people drinking water contaminated with p,p'-DDT and p,p'-DDD as well as low non-cancer risk related to MCPA, MCPP and methoxychlor exposure. At one of the dump sites examined, the level of population exposure to 2,4'-D implies possible hematopoietic, nephrotoxic and hepatotoxic effects as well as reproductive disorders.

Risk assessment is a process based on available scientific information about properties of a given agent, and its effect on biological processes to evaluate potential adverse consequences of exposure to that particular agent. Occupational cancer risk assessment might be considered as a more specific application of the process aimed at finding out whether a particular workplace exposure would lead to cancer. In 1983, a comprehensive model or paradigm of risk assessment was developed by the US National Academy of Sciences (NAS). The overall risk assessment process comprises the following elements: (a) hazard identification, which involves the qualitative determination of whether a particular agent causes a particular adverse effect in humans; (b) dose-response assessment, which describes how such effects are related to the dose; (c) exposure assessment, which estimates the level of human exposure to the substance with and/or without regulatory controls; (d) risk characterization as summary judgments on the existence and magnitude of the public health problem. In this article the authors discuss all the elements of the risk assessment process and present current approaches to this problem as well as research needs in this area.

Background: The major objective of the study was to compare and investigate the usefulness of quantitative analyses of free crystalline silica (FCS) in the assessment of dust exposure in samples of total dust of varied composition, using three methods: chemical method in common use in Poland; infrared spectrometry; and x-ray powder diffraction., Materials and Methods: Mineral composition and FCS contents were investigated in 9 laboratory samples of raw materials, materials, and industrial wastes, containing from about 2 to over 80% of crystalline silica and reduced to particles of size corresponding with that of total dust. Sample components were identified using XRD and FT-IR methods. Ten independent determinations of FCS with each of the three study methods were performed in dust samples. An analysis of linear correlation was applied to investigate interrelationship between mean FCS determinations., Results: In analyzed dust samples, along with silica dust there were numerous minerals interfering with silica during the quantitative analysis. Comparison of mean results of FCS determinations showed that the results obtained using the FT-IR method were by 12-13% lower than those obtained with two other methods. However, the differences observed were within the limits of changeability of results associated with their precision and dependence on reference materials used., Conclusions: Assessment of occupational exposure to dusts containing crystalline silica can be performed on the basis of quantitative analysis of FCS in total dusts using each of the compared methods. The FT-IR method is most appropriate for the FCS determination in samples of small amount of silica or collected at low dust concentrations; the XRD method for the analysis of multicomponent samples; and the chemical method in the case of medium and high FCS contents in samples or high concentrations of dusts in the work environment.

Background: The effectiveness of health protection of workers occupationally exposed to biological agents is equally influenced by the workers' knowledge about the risks related to biological agents and the ways they behave at work., Materials and Methods: In this paper, the authors continue to present the results of the study covering 150 workers employed in health services, forestry, and municipal services. They were interviewed on the basis of a specially designed questionnaire., Results: The majority of the study population used personal protective devices in a proper way and followed the principles of occupational safety and hygiene. Only some of the workers informed occupational medicine physicians about their health problems, which they associated with occupational exposure to biological agents., Conclusion: The interviewed workers are actually able to sufficiently protect their health against biological hazards despite their generally low knowledge of risks related to occupational exposure to biological agents.

Background: The purpose of the study was to evaluate exposure to biological and chemical agents in a sewage treatment plant., Materials and Methods: Sampling was carried out in the summer and wintertime at the morning workshift. Ninety-nine sewage workers taking part in the study were divided into four occupational subgroups: mechanical treatment, biological treatment, sewage sludge treatment, and operation control workers. Exposure to: H2S, SO2, Pb, Cd, Cr3+, Cr6+, endotoxins, (1 --> 3)-beta-D glucans, and microorganisms was evaluated with special identification of Gram-negative rods., Results: The concentrations of dust containing heavy metals and concentrations of gases from all stations did not exceed MAC values. Concentrations of endotoxins ranged from 0.08 to 223 ng/m3, and glucans from 0.00 to 163 ng/m3. The highest concentrations were found among sewage sludge treatment workers, in the summertime (geometric mean value = 37 ng/m3). In the winter, concentrations were almost ten times lower. Over sixty percent of all results exceeded the proposed reference value for airborne endotoxins (10 ng/m3). Concentrations of airborne bacteria in the sewage plant were at low level (10(2)( cfu/m3), except the sludge lagoon and sludge concentration building, where the results exceeded the proposed reference value for mesophilic bacteria (10(5) cfu/m3) "Environmental" bacteria (Pseudomonas, Burkholderia, Shewanella) predominated in the samples. There were also found enterobacteria genus (Enterococcus, family Enterobacteriaceae)--good indicators of hygienic cleanliness of the air., Conclusions: The study proved that the exposure varied and depended on the stage of sewage treatment. The sewage sludge treatment process was characterized by the highest emission of bioaerosols. All microorganisms found in the sewage plant belong to the second occupational risk group, under the ordinance of the Ministry of Health.

Directive 2000/54/EC deals thoroughly with issues referring to the protection of workers from risks related to occupational exposure to biological agents in the European Union. The ordinance of the Minister of Health on harmful biological agents at work and the protection of exposed workers implements its content into Polish legislation. This paper reviews essential records of the ordinance: definition of biological agents; classification of biological agents into four risk groups according to their level of risk of infection; employers' obligations concerning the protection of workers exposed to biological agents. The results of Phare project supporting implementation of the directive in Poland regarding distribution of information on occupational exposure to biological agents among State Sanitary Inspection and occupational medicine service staff and employers are also presented.

Objectives: Numerous epidemiological studies have provided some evidence indicating that workers employed in the pulp and paper industry are at higher risk of death from lung cancer. The present study was undertaken to analyze lung cancer risk prediction among male workers employed in this industry., Materials and Methods: To estimate the probability of death from lung cancer a risk prediction model with some elements of competing risks was used. The risk assessment was based on the cohort study data collected in workers involved in pulp and paper production., Results: Four exposure-response relationship curves were developed adopting the age at the first occupational exposure as a criterion. The model based on the competing risk theory rendered it possible to estimate an additional risk of lung cancer related to a specific period of occupational exposure for the groups adjusted by the age of entering the cohort. For example, in the group with first exposure at the age below 29, the risk changed from 2.25 x 10(-7) during the first year of employment to 1.40 x 10(-5) after 10 years, whereas in the group of workers with first exposure at the age of 50 years, the risk changed from 6.42 x 10(-5) to 4.28 x 10(-4). In addition, the risk at first exposure at the age of 50-59 was almost two orders of magnitude higher than that in workers with first exposure at the age below 29 (6.42 x 10(-5) and 2.25 x 10(-7), respectively)., Conclusions: Using the additional (absolute) risk model involving elements of competing risk theory it is possible to provide a more thorough characteristics of the relationship between the exposure level and probability of death from lung cancer.

Objectives: Owing to a diversified technological process and a great variety of products and materials used in shoe manufacture, workers may be exposed to dusts that contain different chemicals and particles of various shapes and sizes. The aim of this study was to assess the dust exposure, taking account of concentration of particular size fractions according to the European Standard Norm, and to analyze particle size distribution in inhalable dust at selected workplaces in a modern shoe manufacture plant and in a small shoe repair workshop in comparison with other industrial branches., Materials and Methods: In these two workplaces, the concentrations of dust, representing the inhalable, thoracic, and respirable fractions, were measured with the GRIMM 1.105 laser dust monitor., Results: The particle size distribution in inhaled dust in the most characteristic workposts was analyzed. In the shoe manufacture plant, the concentrations ranged from 124 microg/m3 (leather cutting out) to 724 microg/m3 (scouring and milling of soles); concentrations of the thoracic and respirable fractions in the same workposts ranged from 74 microg/m3 to 412 microg/m3 and from 24 microg/m3 to 120 microg/m3, respectively. In the shoe repair workshop, the recorded concentrations were higher: the values ranged from 521 microg/m3 (gluing of shoes and soles, zipper exchange and heel abrasion) to 916 microg/m3 (uppers sewing and heel scouring) for the inhaled fraction; from 335 microg/m3 to 499 microg/m3 for the thoracic fraction; and from 88 microg/m3 to 120 microg/m3 for the respirable fraction. The mass median aerodynamic diameters of inhalable dust particles fell within the limits of 6.2-25.0 mm. Dust with the smallest particles (MMAD = 6.2 mm) was observed in shoe brushing and polishing, and with the largest particles (MMAD = 25.0 mm) in uppers sewing., Conclusions: The modern process of shoe manufacture is characterized by very low concentrations of inhalable dust and its fractions, they are considerably lower than occupational exposure limits in Poland for inhaled (4000 microg/m3) and respirable (2000 microg/m3) dust. In the workplaces under study, a relatively high proportion of extrathoracic fraction of leather dust was found, which supports a hypothesis on a potential etiologic role of this factor in the development of pathologies in the upper airways region.

World-wide epidemiological studies provide evidence that the employment in the shoe production and repair plants is associated with an enhanced risk for cancer (primarily nose and nasal sinuses). According to the majority of authors, it is induced by exposure to leather dust. It is also known that, leather dust particles contain numerous chemicals acquired during the process of leather tanning and finishing (chromium salts, vegetable dye extracts, mineral oils). Some of these compounds exert carcinogenic effect. This paper provides a review of the results of epidemiological studies on health effects of exposure to harmful factors present mainly at the footwear production and repair. These results reveal an enhanced risk for cancer of nose or nasal sinuses induced by leather dust, as well as neoplasms of hematopoietic and lymphatic systems, resulting from exposure to solvents (mostly benzene). Among non-neoplasms, diseases of the musculoskeletal system associated with ergonomic factors, contact dermatics, chronic pulmonary diseases and damage of peripheral nerves in solvent-exposed workers are diagnosed.

The size and technology of the man-made mineral fibers production in Poland is presented. The results of the case-referent and cohort studies aimed at assessing risk for or mortality from respiratory system cancers in populations occupationally exposed to dust containing artificial mineral fibers are also analyzed. The majority of studies focused on the exposure to glass fibers, however, their results revealed no increased risk for cancers in those exposed. As to the increased risk for respiratory system cancers induced by exposure to glass and slag wool fibers, the same proportion of positive and negative results was found in the literature. Most of the studies showed no association between the risk level and the exposure period or cumulative dose. The association with latency period of more than 20 years was only emphasized. This together with the fact that in the majority of studies neither smoking histories nor exposures to other respiratory carcinogens were considered significantly undermine the cause-effect inference. Bearing this mind, it should be concluded that there is an urgent need to undertake further studies with the aim to assess the health risk of exposure to man-made mineral fibers, but only such studies in which besides exposure to fibers, it will be possible to analyze exposure to other coexisting carcinogenic agents.

Background: Numerous studies have indicated an increased risk of lung cancer in pulp and paper industry workers. In a 1990 survey, standardized mortality ratio (SMR) was found to be 122 (95% CI:96-153) for lung cancer in Polish male workers in the pulp and paper industry, and 166 (95% CI:95-270) among workers engaged in paper production., Methods: A nested case-control design within a cohort of pulp and paper workers was applied. Seventy-nine lung cancer cases and 237 "healthy" controls were selected from the cohort of 10,460 workers employed during the years 1968-1990, and observed until the end of 1995. Based on personnel files, occupational exposure was reconstructed by experts. Using a questionnaire, data on smoking habits were collected. ORs unadjusted and adjusted for smoking were calculated applying the model of conditional logistic regression., Results: Occupational exposure to inorganic dusts (kaolin, lime, cement, brick, grindstone) adjusted for smoking was a significant lung cancer risk factor, with a 4.0-fold risk (95% CI:1.3-12.6), and a dose-response by cumulative dose index. Among organic dusts only wood dust increased albeit insignificantly the risk for those exposed (adjusted for smoking OR = 2.1, 95% CI:0.9-4.9), but without dose-response relationship., Conclusions: Exposure to occupational dust with relatively low content of silica, but at high concentrations may be considered as a factor increasing lung cancer risk. However, the observation made in this study should be viewed with caution as it was based on a small number of cases, and further evidence is needed to confirm or refute the authors' hypothesis., (Copyright 2001 Wiley-Liss, Inc.)

The work environment of the rubber industry company, producing various types of tires, was assessed and the workers of the plant were included in a cohort study of mortality. Concentrations of twenty chemical substances at 137 workposts were measured by employees of the plant laboratory and the sanitary and epidemiological station in 1981-1996. The mean values and concentration ranges were determined by departments and workposts. The excess of threshold limit values was analyzed. The workposts with exposure to agents possibly carcinogenic to humans were identified. The analysis performed will render it possible to calculate doses of cumulative exposure to given compounds among workers covered by the epidemiological study.

This paper addresses the problem of diagnosing occupational lung cancer faced in different countries. The risks of lung cancer attributed to occupational exposure in selected epidemiological studies are presented. Evidenced and probable lung carcinogens, as well as occupations and industries responsible for the increased risk for the incidence of this pathology are discussed in the light of epidemiological studies.

The study aimed at assessing cancer risk in a cohort of workers employed in the rubber tire production. The cohort consisted of 17,747 workers (11,660 men and 6087 women) employed in a rubber tire plant for at least three months during the years 1950-1995. The cohort follow-up was completed on December 31, 1995. Deaths by causes were analyzed using standardized mortality ratio (SMR) calculated by the person-years method. The mortality pattern of the general population of Poland was used as the reference. The study indicated significantly lower total mortality in the cohort (men: SMR = 72; women: SMR = 62) as compared to the general population, which is an example of a well known "healthy worker effect". The number of deaths from malignant neoplasms was also lower than expected (men: SMR = 67; women: SMR = 64). Only in a very small sub-cohort of men involved in dosing and mixing of raw material for the production of rubber, an excess of total mortality (SMR = 104) and from all cancers (SMR = 115) was found. Mortality from all neoplasms was enhanced (SMR = 108) in the sub-cohort of women employed in the technical service work area. When analyzing individual cancer sites in men of the whole cohort or sub-cohorts, the observed number of deaths from cancers of the lip, tongue, pharynx, stomach, gallbladder, pancreas, peritoneum, articular cartilage, connective tissue, skin, testis, prostate, bladder, kidney, brain, as well as from Hodgkin's disease, multiple myeloma and leukemia was larger than the expected number. Among women the excess mortality was due to cancers of the large myeloma and leukemia. The SMR calculated for these sites were statistically insignificant. The cohort under study was "young" and thus relatively small numbers of deaths were recorded. The excess mortality, based quite frequently on single cases of selected cancer sites, cannot be regarded as a basis for final conclusions. Nevertheless, the fact that these observations are in agreement with the findings of other authors who carried out studies in the rubber industry of other countries justifies the need to follow-up this cohort in the future.

Power frequency (50 to 60 Hz) electromagnetic fields (EMF) are briefly characterised, EMF sources occurring in the electromagnetic industry are discussed, and methods for and problems involved in the evaluation of individual occupational EMF exposure are also presented. The results of certain cohort industrial and case-referent studies indicate slightly enhanced risk of brain cancer and leukaemia in the group under study. The meta-analysis of the results obtained from numerous studies, published recently, showed a relative risk (RR) of 1.1-1.3 for leukaemia, and of 1.1-1.2 for brain cancer. Only a few studies demonstrate a dose-effect relationship for malignant neoplasms which decreases the power of the hypothesis on the cause-effect relationship. Among health effects of EMF exposure in electric utility workers, other than malignant neoplasms, an increased risk of certain diseases of the circulatory and neurological systems has been reported. The difficulty in the assessment of individual exposure is the main problem in evaluating the relationship between EMF exposure and adverse health effects in electric utility workers. We hope to investigate this further.

This paper describes a cohort study of the mortality among workers employed in one of Polish tyre plants. The scope of the study was limited to the analysis of mortality from main disease categories. Mortality from particular cancer sites will be discussed in a separate publication. The cohort comprised 17,747 workers (11,660 men and 6,087 women) employed during the years 1950-95 for at least three months in the tyre plant. As of 31 December 1995, the follow-up of the cohort was completed. A detailed analysis of mortality by causes was carried out using standardised mortality ratio (SMR) calculated by the person-years method. The general population of Poland was used as the reference. The results indicated general mortality significantly lower in the cohort (men: SMR = 72; women: SMR = 62), than in the reference population. The number of observed deaths from main disease categories was also lower than those expected. The analysis by specific causes revealed significant excess of deaths, due to hypertensive disease among men (36 deaths, SMR = 142; 95% CI: 99-197). SMRs were also calculated in sub-cohorts identified by activities performed (preparatory works: production of tyres and inner tubes; maintenance; storage; others). General mortality in sub-cohorts was similar to that in the total cohort. After analysis by causes of death, some non-significant excess mortality could be observed. It was very small or it applied only to single cases of death. Excess mortality from hypertensive disease in male maintenance workers (21 deaths, SMR = 262; 95% CI: 162-400) was the only exception. The absence of adverse health effects pronounced by significant excess mortality should be attributed to a relatively short period of exposure among the majority of the followed-up workers (over 58% of workers in the cohort employed in the plant for a period shorter than five years) and to their young age. Almost 56% of workers in the cohort were born in the 1950s or later which means that at the end of the follow-up they were not older than 45 years. In order to complete the final mortality assessment the follow-up should continue.

The results of recent epidemiological studies and meta-analysis relating to carcinogenic effects of diesel emissions in exposed populations were reviewed. Statistical, but still not causal association between risk of lung cancer and occupational exposure to diesel emissions was found in a great number of studies under review. Long-term exposure to diesel exhausts (> 20 years) increases by 30-40% lung cancer risk in workers of the transport industry: truck drivers, diesel engine mechanics, locomotive engineers and brakesmen. The results are inconsistent among heavy equipment operators, bus drivers and miners. Relative risk of lung cancer among workers occupationally exposed to diesel emission may be comparable with that of environmental tobacco smoke. Further research is also needed in the area of carcinogenic mechanisms, and biomarkers of exposure should be developed and validated before reliable quantitative estimates of risk of harmful effects to the human health in occupational setting are made.

An analysis of mortality in a cohort of workers employed in the pulp and paper industry, carried out by the authors of this presentation several years ago, indicated an increase of 22% in the risk of mortality from lung cancer. This risk decreased by only 4% after taking account of smoking. The results obtained then were considered as sufficient to undertake further studies aimed at identifying specific occupational factors responsible for an increased risk for mortality from lung cancer in the population under study. The nested case-control study, in which cases (of lung cancer) and controls were selected from the same cohort observed earlier, was approved as the most suitable method for achieving the aforesaid aim. The study covered 79 cases of deaths from lung cancer confirmed by histological and cytological or radiological examinations, and 237 'healthy' controls matched in the ratio of one to three, taking into account gender, date of birth and date of employment. A group of experts carried out in-depth analysis of exposure to harmful factors in each case of death and in each control. Using a questionnaire, specially developed for this purpose, detailed data on smoking habits among persons under study were collected. Odds ratio was used as a measure of a relative risk for death from lung cancer. A crude relative risk and risk adjusted by eliminating the effect of smoking, applying the model of conditional logistic regression, were calculated for individual exposure factors. Smoking proved to be a significant causal factor responsible for the development of lung cancer in the cohort studied. That was evidenced by relative risk accounting for 12.9 for smokers in relation to non-smokers and an enhanced risk with the increasing number of cigarettes smoked daily, the number of smoking years and an accumulated dose. The study does not confirm a hypothesis that chemical factors specific of the pulp and paper industry exert a significant effect on the risk of death from lung cancer. Odds ratios, crude and adjusted for smoking, were lower than one in all distinguished categories of exposure.

A mortality cohort study was undertaken among Polish pulp and paper workers. This paper concentrates on neoplasms mortality among men and women employed continuously for at least one year in the factory producing sulphate pulp, paper board and paper products. A retrospective observation carried out till 31 December 1995 covered 10,460 workers employed during the years 1968-1990. The cohort accessibility was 99%. Cancer risk was evaluated on the basis of standardized mortality ratio (SMR) calculated according to the person-years method. The general population of Poland was the reference population. The results of a 23-year cohort observation, published earlier, showed a lowered overall mortality from all causes and from all malignant neoplasms, and a significant excess of death from peritoneum and prostate cancer among pulp mill male subcohort. The conclusion was drawn that a 'young' cohort and relatively short follow-up period might have affected the results. The results presented in this paper, obtained after further five years of observation showed in the male cohort an excess of deaths from cancer of respiratory tract and peritoneum (lung SMR = 122, nasal cavities SMR = 587, peritoneum SMR = 562). An approximate correction for smoking habits resulted in only 4 decreased risk estimates for lung cancer, indicating a small positive confounding effect of smoking in this material. In female cohort an excess of brain cancer was found (SMR = 355). Only the excess mortality from cancers of nose, lung and peritoneum was coherent with the exposure to higher concentrations of wood dust, pulp, paper and board dust. It may support a hypothesis that these factors as well as dust pollutants, not yet identified in this study, may be considered as one of the risk factors contributing to the incidence of neoplasms of these sites.

Mortality among workers in the Polish pulp and paper industry was evaluated in a cohort study of 10,460 workers who had been employed continuously for at least one year, between 1968 and 1990 in the factory producing sulphate pulp, paper, board and paper products. Three subcohorts were formed according to the work areas. A standardized mortality ratio (SMR) analysis was used to compare death rates for each group exposed with Polish national rates. Mortality from all causes and from all malignant neoplasms, both in the female and in male cohorts was lower than that observed in the general population. In the pulp male subcohort a significantly elevated risk of death from peritoneum cancer (2 obs, SMR = 2,530) and prostate cancer (4 obs, SMR = 854) was recorded, although overall mortality from all causes and from all malignant neoplasms was lower than expected. The excess of deaths from neoplasms in other sites was statistically nonsignificant in all subcohorts. This study did not confirm the excess mortality from lung, stomach and lymphatic cancers found by other authors. The "young" cohort and a relatively short follow-up period (23 years) might have affected the results.

After five successive years of observation the authors present a verified evaluation of the delayed health effects in the pulp and paper industry workers (with particular regard to mortality from malignant neoplasms). The cohort studied consisted of 10,460 workers employed for at least 12 months between 1967 and 1990 in the plants manufacturing sulfate pulp, paper, board and paper products. Subjects were assigned to three subcohorts according to the work areas: 1. pulp mill workers; 2. paper mill workers (paper and board as well as their products); 3. other workers. The workers were enrolled in the subcohort if they were employed for at least one year in one of these departments. One subject could be included in more than one subcohort. The vital status of the cohort was determined through a variety of sources over an observation period of 28 yrs (1967-95). Mortality data were analysed in terms of cause-specific standardized mortality ratios (SMRs) with expected deaths count based on the national mortality rates in Poland. The results of a twenty three-year cohort observation, published earlier, showed the lowered overall mortality (explained by a "healthy worker effect") and the excess of deaths from malignant neoplasms for some sites (peritoneum, prostate, brain). Due to a small number of deaths recorded, kind of exposure and its duration, were left out of the analysis. The results presented in this paper, obtained after five successive years of the male cohort observation, showed an excess of deaths from cancers of the respiratory tract and peritoneum. In the female cohort an excess of brain cancers was found. Only an excessive mortality from malignant neoplasms of the respiratory system was coherent with the exposure to higher concentrations of wood, paper and board dust. An excess mortality from diseases of the circulatory system was found in both males and females employed in paper production.

A cohort study was designed to evaluate the risk of death from malignant neoplasms among pulp and paper workers. This paper presents the evaluation of death risk among workers engaged only in the production of paper, paperboard and paper products. The cohort study covered 1,322 males and 1,914 females employed for, at least, one year in a big pulp and paper mill during the period 1968-90. The study of exposure to harmful factors revealed that concentrations of paper and paperboard dusts in this mill exceeded hygienic standards. The analysis of death risk by causes and gender of those under study was based on standardized mortality rate (SMR) calculated using the method of person-year observation. The general population of Poland was used as reference. The results do not confirm excess mortality from lung, stomach and hematopoietic cancers in paper mill workers reported by other authors. However, an elevated risk of bladder cancer in males (SMR = 491, two deaths) and brain cancer in females (SMR = 353, two deaths) was observed. Both SMR values were not statistically significant. Because of small number of deaths, risk according to exposure and latency was not evaluated.

Diseases of the musculo-skeletal and peripheral nervous systems has become one of the most serious health problems of the working population in Poland. They also make one third of the total sickness absenteeism. The analysis of the magnitude of temporary work disability due to diseases of the spine and spinal cord as well as changes observed over five recent years are presented. The reference material is derived from the national database on sickness absenteeism, covering a 17% random sample of punched cards of certified work disability. The sickness absenteeism is expressed by the number of work disability days per 100 persons employed in a given year. In 1955 the rheumatoid spine diseases proved to be the cause of 194 days of work disability per 100 employed and made 9% of the total sickness absenteeism. In the last five years sickness absenteeism due to these diseases have doubled. In rheumatoid pathologies of the spine, 50% of absenteeism was caused by discopathy. Among diseases of the peripheral nervous system, 78% of absenteeism was caused by diseases of nerve roots and plexus. During the period under discussion a 126% increase in absenteeism caused by these pathologies was noted and it applied mostly to males. In 1995 rheumatoid diseases of the spine as well as diseases of nerve roots and mostly plexus were the cause of 375 days of work disability per 100 employed what made 18% of the total sickness absenteeism. Sickness absenteeism due to these disease has increased by 134% over the last five years. The highest level and dynamics are observed among coal miners.

The pulp mill workers are exposed to substances suspected of carcinogenic effect during production and bleaching of chemical paper-pulp. In order to assess the risk of death from malignant neoplasm, a cohort study covering 1,432 males and 546 females, employed in the sulfate pulp mills of a big cellulose and paper plant, was carried out. Those persons had worked in pulp mills during the years 1967-1990 for, at least, one year. The analysis of risk by causes and gender of those under study was based on standard mortality rate (SMR) calculated using the method of person-year observation. The general population of Poland was used as reference. Significant excess mortality from malignant neoplasm of peritoneum (SMR = 2530) and prostate (SMR = 854) was observed among males, however, the number of observed deaths in these groups was small. Excess female mortality was insignificant. It is rather doubtful whether an increased risk of death from some neoplasms, observed in this group (in this phase of exposure identification) could be linked with occupational exposure.

Mortality among workers in the Polish pulp and paper industry was evaluated in retrospective cohort study of 10460 workers who had been employed continuously for at least one year between 1968 and 1990 in the factory producing sulphate pulp, paper, board and paper products. A standardized mortality ratio (SMR) analysis was used to compare death rates for the exposure group with Polish national rates. For all the subjects death due to all causes and all malignant neoplasms were lower than the number expected. The only significantly increased risks were those of malignant neoplasm of brain among women (4 cases, SMR = 318) and of retroperitoneum and peritoneum among men (2 cases, SMR = 659), exposed to high level of wood dust and irritant sulphur compounds. The authors could not find any etiological explanation of the excessive mortality from brain and peritoneum cancers.

The study covered the work environment of a big plant producing sulfate cellulose, paper and paperboard. Measurements of chemical substance concentrations, performed by a local plant laboratory during the years 1976-1991, were analysed with reference to production departments and particular workplaces. Out of 37 substances under study, 16 were found in the air of workplaces. Their concentrations exceeded periodically hygienic standards. The most frequent excess of TLV applied to such compounds as wood dust (including hard beechwood), non-organic dusts containing 2-50% of crystalline silica and below 2% of silica, welding fumes, furfuryl aldehyde, sulfur dioxide, phenol and hydrogen sulfide. A computer-aided registrer of hygienic data facilitated the follow-up of dynamics of exposure to toxic compounds of workers employed at given workplaces.

The results of various epidemiological research indicate that workers in the pulp and paper industry have an increased risk of developing and dying of malignant cancer with a specific location. The paper discusses recent studies in the area. The findings point to an increased risk of stomach cancer in workers occupationally exposed to pulp produced in the sulfite process. Workers making paper and cardboard are especially at risk for lung cancer. Some researchers signal a higher risk of lymphatic system cancer and stoma cancer. On the basis of existing data on exposure in the pulp and paper industry, it is impossible to determine the exact effects of exposure to a given compound or chemical. Assessment of exposure at particular work areas and analysis of data using the job exposure matrix is necessary. This should provide more information about cancerogenic compounds in the pulp and paper industry.

This work presents an analysis of mortality rates among men and women aged 20-64, by the main causes of death and the places of habitation during the years 1951-1985. Over the investigated period, the percentage of deaths from cardiovascular system diseases, neoplasms, traumas and poisonings among the persons belonging to the professionally active age group increased to ca 80%. The growing trend of deaths in that group was much higher among men than women. This was especially true about the cardiovascular system diseases and malignant neoplasms. Evaluation of mortality rates during the last 20 years by death causes (allowing for age and place of habitation) indicates that the greatest increase of deaths occurred in the group of men aged 40-59 living in the rural environment.

The objective of this work is to present the methodology and basic results of epidemiological studies, which facilitate the evaluation of risk of death from cardiovascular diseases in males of working age, exposed to risk factors related to this group of diseases, in comparison with females. The results revealed that in Poland, social and stressogenic factors determining strong negative life-styles play a significant part in shaping male mortality. These factors, acting in combination with high rates of hazards such as smoking, arterial hypertension, obesity and diabetes, significantly increase mortality from cardiovascular diseases.

The objective of this work was to present the plan and methods of an epidemiological study of the risk of death from cardiovascular diseases in males and females of working age exposed to risk factors related to this group of diseases. The survey covered random samples of the general population, 20-64 years of age, living in areas of two regions (voivodeships) as well as families of all the decreased from cardiovascular diseases, coming from the same areas. Data on risk factors characteristic for this group of diseases in the general population and in the decreased were obtained. The method of assessment of death risk in persons exposed to given factors is presented. In the method, a standardized mortality ratio (SMR) was used. Organization of the study and its results will be discussed in Section II of this work.

The paper presents the results of this study on mortality rate during the period of 1951-1985 for men and women aged 20-64. Moreover, the differences between male and female mortalities were analysed with a view of investigating the problem of excessive mortality ratio of men. In the period under study the descending and then ascending tendency of the mortality rate could be observed both in the male and female populations. Up to 1965 male mortality decreased gradually (by 35%) whereas the following years witnessed considerable rise of the level of male mortality (by 30% to 1985), which referred especially to males at the age range between 40 and 49, years. As regards the female population the mortality rate was decreasing till 1975. For the last 10 years increased female mortality has been observed, however, their dynamics is much more lower than that for the female group (by 6.2% less than for 1975). During the whole period examined i.e. 1951-1985 the excessive mortality ratio in men was found to be higher by 60.4%. High dynamics of the ratio concerned male population at lower age ranges.