Determination of Environmental Exposure to Asbestos (Tremolite) and Mesothelioma Risks in the Southeastern Region of Turkey

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1 Determination of Environmental Exposure to Asbestos (Tremolite) and Mesothelioma Risks in the Southeastern Region of Turkey ABDURRAHMAN SENYIGIT Dicle University Faculty of Medicine Department of Chest Diseases Diyarbakir, Turkey ABDURRAHMAN DALGIC ORHAN KAVAK Dicle University Faculty of Engineering Mining Department Diyarbakir, Turkey ABDULLAH CETIN TANRIKULU Diyarbakir Bilim Health Center Diyarbakir, Turkey ABSTRACT. In this study, the authors examined the concentrations and mrneralogical analyses of asbestos, and investigated mesothelioma risk in southeastern Anatolia, Turkey. They used a gravimetric dust sampler to collect samples from 2 villages and 2 asbestos mines (1 active). Samples were then evaluated by an X-ray diffractometer and an electron microscope. The authors found high concentrations of asbestos in an active mine (4.9 fibers[f]/cm*) and at a house that was plastered with asbestos {1.24 f/cm^) and had a very active population. They found a low concentration ( f/cm^) in indoor measurements taken in village, and an even lower concentration ( f/cm') in the inactive mine environment. Outdoor measurements included a low concentration of f/cm^ in the village environment, and a high concentration of 1.17 f/cm^on the mine road during the passing of a sheep herd. The people in the region are continuously exposed to asbestos during normal activities. This cumulative exposure to asbestos carries sufficient risks for mesothelioma development. <Key words: environmental asbestos exposure, malignant mesothelioma, mineralogical analysis> EPIDEMIOLOGICAL STUDIES have demonstrated strong correlations between exposure to asbestos fibers and development of a variety of pulmonary diseases.'"^ Turkey has large asbestos deposits, as do many countries in the world, but the prevalence of endemic asbestosrelated pulmonary disease in Turkey is high relative to otber countries.''' Asbestos deposits have been used for many years by rural inhabitants to make a whitewash or stucco for the walls, floors, and roofs of their houses, and also as a substitute for baby powder in the southeastern region of Turkey (Anatolia). Inhabitants of the region are exposed to asbestos from childhood."'^ Malignant mesothelioma is an incurable disease caused by inhalation of asbestos fibers. The people living in southeastern Turkey were reported to bave a bigh incidence of mesothelioma because of their environmental exposure to asbestos.^ A comprehensive study was conducted on asbestos exposure in the region, in which asbestos levels were measured in all possible places to determine the average cumulative inhalation of asbestos in the daily lives of the inhabitants. Because they are continuously exposed to asbestos, cumulative exposure becomes an important factor for health considerations in the region. The provision of a healthy environment is both cost-effective and humanitarian. The productivity and quality of life of the inhabitants in this region are correlated with environmental quality. Tbe environmental quality is the chemical composition of air broadly defined as any undesirable substance not normally present in air or present in an excessive amount."' 65 Archives of Environmental Health

2 Mectiterranean S6a CYPRUS Fig. 1. Location of the field study. Materials and Method Field studies were performed in September Sampling locations were previously determined by the number of patients with mesothelioma in the region. The region is 3000 km^, lies between Elazig and Diyarbakir provinces, and is within the southeast Anatolian thrust belt of Turkey (Fig. 1). Samples for dust measurement and mineralogical analyses were collected at 2 villages, and Yukari^eyhler, and in the vicinity of the mines where high mesothelioma risk had been previously determined. People in the region still mine and use large amounts of asbestos. Dust surveys. We used the SKC gravimetric dust sampler (SKC Ltd., Dorset, UK) (Fig. 2). It measures the dust exposure of individual subjects in a particular operation or location. The sampled air is drawn through a membrane filter by a small electrically driven pump. In the sampling study, we used the special MCE gridded filters with 0.- jm pore size tor asbestos fibers of 25 mm diameter. The flow rate of the personal dust sampler was adjusted to 2.1 L/min for outdoor measurements, where people were active, and 1.9 L/min for indoor measurements. After sampling, we removed the filters and placed them into a special cassette for transport. Air fiber concentrations were determined by specialists at the laboratory of the National Institute of Workers Health and Security, Ankara, by counting fibers >5 jjm long on these filters, using a phase-contrast microscope. Mineralogical surveys. The mineralogy of the mines was determined with samples we collected from indoor walls ot' some houses, and mine deposits at both villages. The samples were evaluated with an X-ray diffractometer (Philips, PW 3710 and Rigaku, 2200 Dmax) and electron microscope ()EOL IM-40A SEM/LDS) at laboratories of the National Institute of Mineral Research and the Turkish Petroleum Corp., both in Fifl. 2. Dust sampling instrument. Ankara. Fig. 3 shows the composition of the sample under electron microscope. X-ray diffraction analysis is given in Fig. 4. All samples were analyzed to assess the actual composition of the asbestos mineral. Results In this study, dust concentration was measured outdoors, at roads to both active and inactive mines, inside houses in the two villages that were plastered with asbestos, and at free areas in the villages. Maximum allowable asbestos concentration (MAC) in a working environment is 0.1 f/cm^ (fibers/cm^) according to the official Turkish law of health and safety. MAC is the December 2004 [Vol. 59 (No. 12)] 659

3 MgO SiO2 CiO Fe2O3 16,560 4,045 20,012 15, ,000 Eh Ijot 0 K» Mg Kl SI Kl Ci Kl Fe Kl Cone 42,492 wlw 9,9 m% 22,43 «l% 14,303 wtw 10,759 wtw 100,000 wtw kv 20,0 Tike off At^ 40,0 ElKied Lnetme 30,0 Cutsoi=O,005 ktv Ocnl Vent 197 Window 0,005-40,005 = 6460 cnt Fig. 3. Results from scanning electron microscopy of samples. Peaks represent the incidence of elements found in asbestos (tremolite) ore, and detailed concentrations of components inside asbestos (tremolite) ore are shown to the right. 350 e 300 o i 250 I" 200 Ferro actinolite Ferro actinolite were engaged in various activities such as playing games and dancing. Seven samples were analyzed with the X-ray diffractometer and 4 samples were evaluated by electron microscope. Results from both methods showed that all samples were tremolite, which formed in the base of metamorphosed serpentine formations in this region., -150 Calcite Discussion Wavelength (+20) Fig. 4. X-ray diffraction analysis of asbestos. Peaks indicate incidence of elements found in asbestos (tremolite) ore. airborne concentration of substances and conditions under which nearly all occupants may be repeatedly exposed without adverse health effects." The results of dust measurements and types of mineralogical analyses are given in Table 1. The first sample was received from inside a house, where no one lived. The second and third samples also were taken from indoor environments, but where there were very dense populations and sweeping had taken place during sampling. The highest asbestos concentration was measured in the fourth air sample from the active mine. The fifth sample, also remarkably high, was taken from the road to the active mine during the passing of a sheep herd, which made the road dustier. The last three samples were taken outdoors, where people 60 Asbestos has been extensively used in industry and construction in the 20th century, especially during and after the Second World War. Although the mineral is no longer used in developed countries, the total world production remains high.'^ Hillerdal reported occupational asbestos exposure levels of 25 f/cm', with levels as high as 1,000 f/cm' to 2,000 f/cm' for workers who were first exposed to asbestos in the past. Peak exposure in the 1960s was 20 f/cm\ which was substantially reduced over subsequent years.*'" Occupational asbestos exposure levels are generally assumed to be higher than environmental exposure levels. Workers in asbestos industries are exposed only hr/day, but people living in the area of this study are continuously exposed to asbestos. Environmental concentration of asbestos in the region is high, and for some people the effect is similar to that for workers employed in the industry. Cumulative asbestos deposits in the lungs of a 50-yr-oId man in a rural environment containing asbestos are nearly equal to deposits in the lungs of a 50-yr-old worker who has been employed for 20 yr in the asbestos industry.** Mineral dust, tremolite, and diseases caused by exposure to these substances have been reported as major health concerns in the southeastern part of Turkey.^'*''''^ 660 Archives of Environmental Health

4 Table 1. Description of the Sampling Process Sample no. yillage Sample location Duration (hr) Concentration of asbestos (f/cm') X-ray SEM/EDS Yukan^eyhler Yukari^eyhler Yukarijjeyhler indoor indoor indoor mine (active) mine road outdoor mine (inactive) outdoor , , Note: SEM/EDS = scanning electron microscopy. ( + ) = Analysis was performed, (-) = Analysis was not performed. Indoor = houses plastered with asbestos. Outdoor = free areas inside the villages. In a room where the walls have been recently whitewashed or where the floor is being swept, the concentration of asbestos can be quite variable, ranging from 0.02 f/cm' to 17.9 f/cm'.^ In another study, the indoor air fiber concentration in villages using asbestoscontaminated white soil was 0.14f/cm^ before the floor was swept, and 0.94 f/cm^ afterward.^ We found indoor airborne asbestos fiber concentrations ranging from f/cm' to 1.24 f/cm^ in villages using asbestoscontaminated white soil. This finding clearly demonstrates that the mesothelioma risk is as high for villagers exposed to asbestos as for those who are exposed occupationally. We found a high asbestos concentration (1.24 f/cm^) at a house with a dense population. All members of a family frequently come together in a room as a necessity of village life. Therefore, environmental asbestos concentration increased as well as the exposure. Vast amounts of mineral dust are produced by erosion of natural deposits at the surface of soil from heavy fracturing, poor vegetation, and climatic conditions in various parts of Turkey. Moreover, rural exposure can be enhanced by various activities, such as farming or the passing of a herd of sheep in the street.^''' The airborne fiber level was previously estimated to have increased up to 200 f/cm^ in the immediate environment during the crushing process of asbestos (tremolite) ore.^asbestos is used for plastering and painting houses in the region. The application of white soil as whitewash is usually done each year by grinding the soil into a powder and suspending the powder in water. Some measurements showed low concentrations of asbestos from materials that are mixed with the soil for better compaction after the application of whitewash. Environmental asbestos exposure levels are usually lower than occupational levels, but the cumulative asbestos exposure levels may be similar. In this region, environmental exposure to asbestos fibers was 0.16 f/cm^, which was higher than the asbestos concentration permitted by regulation. Therefore, the mesothelioma risk for people living in this environment was as high as the risk for people who are occupationally exposed.''-^ '^ Mesothelioma incidence in 2000 was estimated at 12.5 cases per 1 million inhabitants in the United Kingdom, 1 case per million in Germany, and 42.9 cases per million in southeastern Turkey.^ The epidemiologic features of parenchyma and pleural diseases related to asbestos exposure are variable.'^''"^ Patients with pleural plaques, pleural fibrosis, and mesothelioma disease have lower fiber numbers than those patients with asbestosis.'^ Wagner et al.'^ reported 33 cases of mesothelioma in a South African asbestos mining community in Cases of malignant pleural mesothelioma have occurred frequently in developed countries in the past decades, Mesothelioma risk in southeastern Turkey seems to be higher than in developed countries.^ In regions with high environmental levels of asbestos, either from natural pulverization of rocks, mining, or other activities (e.g., construction of buildings with fiber-rich stucco), considerable environmental exposure is inevitable unless particular care is taken. Otherwise, the cumulative fiber doses experienced by members of the exposed population will be associated with a high risk of developing mesothelioma. The authors gratefully acknowledge the assistance of Prof. Dr, Muzaffer Metinta^ and Assoc. Prof, Dr. Meliksah Ertem; theyalso thank the Estahlishments (National Institute of Workers Health and Security, Ankara; Turkish Petroleum Corp.; and the National Institute of Mineral Research) for sample analyses. Submitted for publication July 20, 2005; accepted for publication September 1, Reprint requests should be sent to Dr, A, Dalgic, Dicle University, Engineering Faculty, 2120 Diyarbakir, Turkey, adalgic@dicle.edu.tr Copyright 2006 Heldref Publications * * * * * * * * * * December 2004 [Vol. 59 {No. 12)] 661

5 References Baris Yl, Sahin AA, Ozesmi M, et al. An outbreak of pleural mesothelioma and chronic fibrosing pleurisy in the village of Karain/Urgup in Anatolia, Thorax 197; 33(2): Hansen ), de Klerk NH. Musk AW, et al. Environmental exposure to crodicolite and mesothelioma. Exposureresponse relationship. Am J Respir Crit Care Med 199; 157n): Metintas S, Metintas M, Ucgun I, et al. Malignant mesothelioma due to environmental exposure to asbestos: follow-up of a Turkish cohort living in a rural area. Chest 2002; 122(6): Senyigit A, Dalgic A, Kavak O. Health effects of asbestos. Dicle University, J Dicle Med 2004; 31(4):4-52. Senyigit A, Babayiglt C, Cokirmak M, et al. Incidence of malignant pleural mesothelioma due to environmental asbestos fiber exposure in the southeast of Turkey. Respiration 2000; 67:610^. Emri S, Demir AU. Malignant pleural mesothelioma in Turkey, Lung Cancer 2004; 45:1 7-20, Emri S. Recent developments on therapy of malignant pleural mesothelioma. Presented at the International Cancer Symposium, Ankara, Turkey, Coplu L, Dumortier P, Demir AU, et al. An epidemiological study in an Anatolian village in Turkey environmentally exposed to tremolite asbestos. J Environ Pathol Toxicol Oncol 1996; 15: Dumortier P, Coplu L, de Maertelaer V, et al. Assessment of environmental asbestos exposure in Turkey by bronchoalveolar lavage. Am J Respir Crit Care Med 199; 15: Aluclu I, Dalgic A. A case study on natural ventilation characteristics of the Diyarbakir Surici [Old City) Municipality Building in Turkey. Building Environ 2005; 40: Hillerdal G, Mesothelioma: cases associated with nonoccupational and low dose exposures. Occup Environ Med 1999; 56: Yazicioglu S, Oktem K, llcayto R, et al. Association between malignant tumors of the lung and pleurae and asbestosis. A retrospective study. Chest 197; 73:52-6, 13. Wagner JC, Sleggs CA, Marchand P. Diffuse pleural mesotheiioma and asbestos in the North Western Cape Province, BrJ Ind Med 1960; 17: Peacock C, Copley SJ, Hansell DM. Asbestos related benign pleural disease. Clin Radiol 2000; 55: Decision editor: Kaye H. Kilburn, MD 662 Archives of Environmental Health

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