While exposure to asbestos is by far the most common cause of mesothelioma, links have been made between mesothelioma and other substances. One of these substances is zeolite, a natural mineral that in some forms looks and acts very much like asbestos.
Known scientifically as hydrated alkali aluminum silicate, zeolites are a group of minerals that contain mostly hydrated aluminum and silicon compounds. Natural forms of zeolite are created by the combination of volcanic rocks, ash, and alkaline groundwater, which means they often can be found near active or dormant volcanos.
There are more than 50 zeolites that come in many different forms. According to the United States Geographical Survey (USGS), the most common forms of naturally occurring zeolite are:
Zeolites are found in volcanic rock and ashes, and they are sometimes used as additives in animal feeds. Because of their porous structure, zeolites may be used as absorbents, desiccants, detergents, and as water and air purifiers.
In the United States, natural deposits of erionite have been located in a handful of western states, particularly Arizona, Nevada, Utah, Oregon, North Dakota, South Dakota, and Montana. A report on zeolite in the U.S. notes that residents of what is considered the “intermountain West” may be exposed to fibrous zeolite in ambient air, and therefore may be susceptible to the development of mesothelioma. North Dakota is currently conducting a study relating to erionite exposure among residents of that vast mountainous state.
Only one of type of zeolite – erionite – has been specifically linked with mesothelioma.
Zeolites and Mesothelioma
There is a strong link between one form of fibrous zeolite (erionite) and mesothelioma. This connection has been studied by scientists, physicians, and medical researchers for several decades.
One of the earliest indications that exposure to certain forms of zeolite might lead to malignant mesothelioma was based on a study of mortality rates in the Cappadocian region of Turkey starting in the late 1970s. After noticing the high incidence of mesothelioma in several Turkish villages – Karain, Tuzkoy, Old Sarihidir, Karlik, and Boyali – a team of international researchers went to the region and discovered that the cause was a fibrous zeolite compound known as erionite. After a 23-year study that followed 891 men and women who lived in three of these villages, the researchers determined that the pleural mesothelioma death rate was 44.5 percent in the village that had erionite exposure.
Subsequently, a number of studies brought the connection even closer. In 1984, Suzuki and Norihiko published a study showing that fibrous erionite “frequently produced malignant peritoneal tumors after long latency” in laboratory mice. In fact, nearly one fourth of the mice that were exposed developed the deadly cancer. The mesothelioma tumors induced by the erionite were similar to those induced by asbestos.
The next year, several medical researchers from Wales published a study on the effects of different zeolites in rats. This study produced an even stronger connection between zeolite and mesothelioma, with the researchers stating, “In this zeolite experiment virtually all the animals died with mesothelioma with induction periods ranging from less than 400 days.” It’s worth noting that mesothelioma also was induced in several rats exposed to other forms of zeolite, though given the small number of cases, those results remain inconclusive.
Due to the relationship between erionite and mesothelioma The International Agency for Research on Cancer has listed this form of zeolite as a Group 1 substance, which means it is carcinogenic in humans. Zeolites other than erionite are classified as Group 3, which means they are not classifiable as carcinogens. However, it is possible that with further research, Group 3 substances may be classified differently.
Zeolite Detox and Other Uses
Because of its high-absorption properties, zeolite has been tested as a method of decontaminating bodies of water. For example, clinoptilolite has been used successfully to remove certain pathogenic microorganisms, ammonium, and heavy metals from wastewater and seawater, and applications in urban areas, where high quantities of water are used and discarded regularly, are promising. In addition, some forms of zeolite have been used successfully as a dietary supplement for certain animals, including chickens, pigs, and even bees. In several cases, zeolite seems to have improved certain biological functions in certain animals, such as removing parasites.
In recent years, some forms of zeolite have become popular for use in various dietary supplements for humans as a method of removing heavy metals from the body. Proponents of the health benefits of zeolite have also used it for everything from hangovers to adjuvant therapy for certain types of cancer. None of these uses are approved by the U.S. Food and Drug Administration (FDA).
Ultimately, there is a lack of data supporting the efficacy of zeolite as a dietary supplement. There is no clinically conclusive evidence that shows whether zeolites are safe to ingest.Sources
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