Erionite exposure in North Dakota and Turkish villages with mesothelioma

Abstract

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. asbestosis | cancer | carcinogenesis | environmental carcinogenesis | mineral fiber carcinogenesis

Mesothelioma: recent highlights

“…However they are unregulated and their use is not restricted in spite of ample evidence that some of them (10), but not all of them (11), are as or more carcinogenic than the regulated mineral fibers (12). For example gravels containing erionite, to date the most potent fiber in causing mesothelioma, was used to pave over 300 miles of roads in North Dakota (10). Also, roads and urban developments were built over asbestos deposits present in the ground in Nevada (13).…”

Novel systemic therapy against malignant pleural mesothelioma

“…The incidence of MPM in the United States has stabilized over the past few years likely due to decreased asbestos use since the 1970's (1); however, the incidence of MPM in developing countries is expected to increase and represents a substantial health and economic burden (6,7). Risk factors for mesothelioma also include environmental, occupational, and para-occupational exposure to asbestos and other mineral fibers such as erionite (8). Prior chest radiation therapy or occupational radiation also increases the risk for developing mesothelioma (9)(10)(11)(12)(13)(14)(15).…”

In vitro experimental models of mesothelioma revisited

“…Carbone et al sought to clarify the biologic effects of erionite in HMC by co-culturing with macrophages in a dual chamber set-up that mimicked (proposed in vivo events) the process of inflammatory cell recruitment and activation at sites of fiber deposition (53). After a prolonged culture period, 3D foci developed, consistent with their interpretation of cellular transformation, in only those erionite-exposed HMC with macrophages but not in unexposed HMC with macrophages.…”

“…Others Erionite is a silicon-based asbestiform fiber belonging to the mineral class of zeolites found to be naturally occurring in rock formations throughout worldwide locations with known epidemiologic link to MPM (53). Although it is accepted that erionite is a carcinogen (64,65), the molecular mechanism(s) responsible for its toxicity remain obscure with recent recognition that iron, previously thought to be the critical element driving carcinogenicity (66), is not even part of the erionite crystal structure (67).…”