Y. Izzettin Baris

A mesothelioma epidemic in Cappadocia: scientific developments and unexpected social outcomes

In Cappadocia, Turkey, an unprecedented mesothelioma epidemic causes 50% of all deaths in three small villages. Initially linked solely to the exposure to a fibrous mineral, erionite, recent studies by scientists from Turkey and the United States have shown that erionite causes mesothelioma mostly in families that are genetically predisposed to mineral fibre carcinogenesis. This manuscript reports, through the eyes of one of the researchers, the resulting scientific advances that have come from these studies and the social improvements that were brought about by both the scientists and members of the Turkish Government.

ENVIRONMENTAL MESOTHELIOMA IN TURKEY

The geologic structure of Turkey reveals that certain parts of Anatolia are rich in asbestos minerals. However, the literature concerning asbestos-related diseases was initially confined to case records of mesothelioma. The fact that asbestos could be considerably hazardous to health and create a major public health problem for this country was first suggested by the epidemiologic studies of the Chest Diseases Division of Hacettepe University carried out in asbestos mines and mills around MihalliqqikEskisehir and Sivas in 1972. In these studies, emphasis was placed on calcified pleural plaques and pulmonary fibrosis. The scope of these studies was widened to include the villages of Mihalliqqik and Maden-Elazig for investigation of the effects of environmental exposure to asbestos in peasants in rural regions. Similar surveys were conducted by Yazicioglu et al. in 1973-5 in southeastern Turkey. Our recent epidemiologic studies have revealed that asbestos-related diseases, primarily calcified pleural plaque (CPP), chronic fibrosing pleuritis (CFP), and malignant pleural mesothelioma (MPM), are endemic in some villages with or without asbestos deposits. This paper describes briefly the studies of the Chest Diseases Division of Hacettepe University of environmental asbestos-related diseases in Turkey.

Erionite exposure in North Dakota and Turkish villages with mesothelioma

Exposure to erionite, an asbestos-like mineral, causes unprecedented rates of malignant mesothelioma (MM) mortality in some Turkish villages. Erionite deposits are present in at least 12 US states. We investigated whether increased urban development has led to erionite exposure in the United States and after preliminary exploration, focused our studies on Dunn County, North Dakota (ND). In Dunn County, ND, we discovered that over the past three decades, more than 300 miles of roads were surfaced with erionite-containing gravel. To determine potential health implications, we compared erionite from the Turkish villages to that from ND. Our study evaluated airborne point exposure concentrations, examined the physical and chemical properties of erionite, and examined the hallmarks of mesothelial cell transformation in vitro and in vivo. Airborne erionite concentrations measured in ND along roadsides, indoors, and inside vehicles, including school buses, equaled or exceeded concentrations in Boyali, where 6.25% of all deaths are caused by MM. With the exception of outdoor samples along roadsides, ND concentrations were lower than those measured in Turkish villages with MM mortality ranging from 20 to 50%. The physical and chemical properties of erionite from Turkey and ND are very similar and they showed identical biological activities. Considering the known 30- to 60-y latency for MM development, there is reason for concern for increased risk in ND in the future. Our findings indicate that implementation of novel preventive and early detection programs in ND and other erionite-rich areas of the United States, similar to efforts currently being undertaken in Turkey, is warranted.

Environmental fiber-induced pleuro-pulmonary diseases in an Anatolian village: an epidemiologic study.

This study was designed to determine the prevalence of pleural mesothelioma and other malignancies in the Anatolian village of Tuzköy, where neither asbestos nor any environmental carcinogen has been detected. Another village (Kizilköy) located 12 km from Tuzköy was selected as a control. Three hundred twelve subjects from Tuzköy who were at least 25 yr of age and 95 subjects from Kizilköy were studied. Analysis of X-rays of the Tuzköy group revealed that subjects had calcified pleural plaques (17%), pleural thickening (10.5%), obscured costophrenic angles (15%), and diffuse interstitial pulmonary fibrosis (12.1%). Sixty-seven deaths were records in Tuzköy during the previous 3 yr, 41 of which resulted from malignant diseases. There were no X-ray abnormalities or deaths resulting from malignancies in the control group. Because of the high incidence of mesothelioma and lung cancer which usually results from asbestos exposure, the presence of asbestos in Tuzköy was investigated, but none was detected in spite to Tuzköys volcanic location. Nevertheless, zeolite, an asbestiform mineral, was detected in the stones of buildings and in the village soil, as well as in the lung and pleura of the patients during biopsy. Thus, this mineral was considered to be responsible for the fiber-induced pleuro-pulmonary diseases in Tuzköy. No zeolite was found in the soil and stones of the control village.

Bee and wasp venom allergy in Turkey

BACKGROUND Beekeeping has progressed recently to where bee sting exposure is an important public health problem in Turkey. OBJECTIVE To investigate the status of bee and wasp sting allergy in a region of Turkey. METHODS We conducted a questionnaire-based study of 786 subjects (cellulose paper factory personnel and family members older than 16 years of age) in Cay town of Afyon. Skin prick test with common aeroallergens and measurements of total IgE and specific IgE for bee and wasp venom were performed in 212 randomly selected subjects. RESULTS Cumulative lifetime sting rate was 94.5% (geometric mean: 6.1 times), and last year bee sting rate was 20.4% (geometric mean: 1.6 times). Subjects who had beehives had higher risk of bee sting (P < .05) in the last year, whereas there was no significant difference among the groups for the cumulative lifetime sting exposure. Severe and mild systemic reactions were noted in 2.2% and 5.3%, respectively. Emergency room visits were reported in 9.3%, and familial Hymenoptera allergy in 10.2%. Fatal potential of bee sting was known by 81%. There was no mortality related with Hymenoptera allergy in records of the last 5 years. In 24 subjects with multiple sting exposures, allergic reactions changed severity in the latter exposures, which became less severe in five and more severe in 19 subjects. Atopy rate detected by prick testing was 20.3%. Specific IgE levels were class 1 in 22, class 2 in 11, and class 3 in 2 subjects for bee; and class 1 in 24 and class 2 in 2 subjects for wasp. Nobody had received immunotherapy for venom allergy. None of the factors including atopy, sex, occupation, smoking and family history of bee sting was significantly related with severity of the systemic reaction (P > .05). CONCLUSIONS Bee and wasp stings are prevalent in Turkey. Severe systemic reactions complicating the sting are frequent (2.2%). Public awareness of potential fatality and treatment of the allergic reaction is not adequate.

Clinical and Radiological Study in Sepiolite Workers

Radiological findings were evaluated on a mass survey (70 mm films) in four villages where mining and processing of sepiolite have occurred for more than 100 yr, together with a clinical and radiological study in 63 sepiolite trimming workers in Eskisehir, Turkey. Mineral fiber-related pleural diseases were not detected in those people who were exposed to sepiolite dust. Although pulmonary fibrosis was encountered in 10 of 63 workers, no relationship between pulmonary fibrosis and sepiolite inhalation could be established. In contrast, all fibrotic patients were smokers and came from dusty rural regions where tremolite (asbestos) and zeolites are present. Three of them had also worked in dusty fields.